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Animal Systems

Animal Systems

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Animal Systems. 1.Describe how nutrients and oxygen are moved to the body cells. 1 .1Review the principles of diffusion and active transport. 1.2Contrast passive transport systems with active transport systems. 1 .3Compare open circulation systems with closed systems of vertebrates. - PowerPoint PPT Presentation

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Page 1: Animal Systems

Animal Systems

Page 2: Animal Systems

1. Describe how nutrients and oxygen are moved to the body cells.

1.1 Review the principles of diffusion and active transport.1.2 Contrast passive transport systems with active transport systems.1.3 Compare open circulation systems with closed systems of vertebrates.1.4 Compare the efficiencies of hearts with one, two, three, and four chambers.1.5 Describe the blood circulation pattern and vessels in the mammalian systems.

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To begin...

What is the definition of each of the terms listed below and what does each have to do with transport?

Diffusion: the movement of molecules from an area of high concentration to an area of lower concentration

Passive transport (osmosis): the movement of molecules, across a cell membrane, by their own energy

Active transport (exocytosis, endocytosis): the movement of a substance through a cell membrane, requiring the use of ENERGY!

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One main transport system--the circulatory system...Your body is made up of billions of cells. Each cell is like a tiny factory because it must be supplied with certain chemicals and it must be "relieved of" certain waste products.

The 3 methods of transport mentioned earlier all work together to deliver these needed chemicals to each cell (such as oxygen and food) and to pick-up/remove the waste products (e.g. carbon dioxide gas).

Also, these 3 methods of transport are, more importantly, a part of one main system known as the CIRCULATORY SYSTEM. Although, when discussing the movement of oxygen and nutrients in simple organisms, we usually just talk about a "transport system" as there is no blood involved...only in more complex animals do we begin to see blood, hearts, vessels, etc.

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In various organisms, the type of transport system used will vary...

1. In some multicellular organisms, such as a sponge, almost every cell has part of its surface exposed to the environment. Each cell can obtain its own oxygen and get rid of its own wastes. In these cases, diffusion and active transport are sufficient for moving substance into cells.

2. In roundworms, there is a fluid-filled body cavity surrounding the digestive tube. As the roundworm wiggles, the fluid is squeezed about from one place to another. In this way, substances dissolved in the fluid are carried to and from body cells.

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Comparison of the transport systems, continued...

3. In arthropods (crayfish, lobsters, insects), the blood is pumped through blood vessels that empty into body spaces. Through these spaces, the blood moves about sluggishly, in contact with tissues. Eventually it gets back into another set of vessels. These carry it back to the pumping point. This type of incomplete vascular system is called an open circulatory system.

4. Annelids (earthworms) have a closed circulatory system. In this system, blood flows within vessels all the time. An earthworm has five hearts and a complicated set of finely branched vessels. In this way, all body cells are located relatively close to a blood vessel so that they can obtain food and exchange wastes. They do this through diffusion and active transport.

5. In vertebrates, circulation also occurs in a closed system. A single, muscular heart with two or more chambers pumps blood through the system.

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Review...

1. What type of transport system is the most developed? Why?

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1. Describe how nutrients and oxygen are moved to the body cells.1.1 Review the principles of diffusion and active transport.1.2 Contrast passive transport systems with active transport systems.

1.3 Compare open circulation systems with closed systems of vertebrates.1.4 Compare the efficiencies of hearts with one, two, three, and four chambers.1.5 Describe the blood circulation pattern and vessels in the mammalian systems.

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Two Important Definitions...

Atrium: chambers on the upper side of the heart that receive blood from the veins and in turn force it into the ventricles

Ventricle: chambers on the lower side of the heart that receive blood from the atria and in turn force it into the arteries (vessels that carry blood away from the heart and around to the rest of the body)

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Different types of hearts exist in vertebrates...which one is best??

1. Fish: a 2-chambered heart- single loop of blood, closed system1. loop begins in the atrium (chamber #1), which acts as a chamber to receive the de-oxygenated blood that has been circulated around the body2. from the atrium, blood is passed to the ventricle (chamber #2) which pushes deoxygenated blood to the gills3. gills remove CO2 and replace it with O2, oxygenated blood is circulated around the fish and the body of fish uses up O2, leaving de-oxygenated blood4. de-oxygenated blood is carried back to the atrium

atrium ventricle gills bodyPros: no mixing of oxygenated and de-oxygenated bloodCons: heart must pump blood through gills and body in 1 circuit

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2. Amphibian: 3-chambered heart1. the loop begins simultaneously in the right atrium (chamber #1), this chamber collects de-oxygenated blood from body, and the left atrium (chamber #2), this chamber collects oxygenated blood from the lungs2. the heart contracts and drains both atriums into the ventricle (chamber #3) at the same time (ventricle receive a mixture of oxygenated and de-oxygenated blood)3. ventricle contracts and forces mixed blood to the lungs and to the body

 body right atrium ventricle lungs left atrium

Pros: ridges in walls of blood vessels reduces mixing of both kinds of bloodCons: body receives a mixture of oxygenated and de-oxygenated blood

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3. Birds and Mammals: 4-chambered heart- most efficient circulatory system, double loop, blood doesn't mix3. First Loop: a) Pulmonary Circulatory System: - right atrium collects de-oxygenated blood from the body and it drains   through the right tricuspid valve into the right ventricle - this blood is pumped into the lungs to pick up O2, it then goes to the   left atrium Second Loop:  b) Systemic Circulatory System: - left atrium receives oxygenated blood from the lungs, which drains   through the left bicuspid valve into the left ventricle - this blood is pushed to the whole bodyImportant Notes:- although there are two separate loops for the blood to follow, both occur simultaneously- This means that blood is pumped through the right side of the heart to the lungs at the same time that blood is received from the lungs and pumped throught the left side of the heart to the rest of the body

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Diagram of the Flow of Blood in a Mammalian Heart

body right atrium tricuspid valve right ventricle

lungs left atrium bicupsid valve left ventricle

Pros: heart is a double pump  no mixing of oxygenated and de-oxygenated blood

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HOW BLOOD TRAVELS THROUGH THE BODY

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Review...

1. What type of heart is most efficient? Why?

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1. Describe how nutrients and oxygen are moved to the body cells.1.1 Review the principles of diffusion and active transport.1.2 Contrast passive transport systems with active transport systems.1.3 Compare open circulation systems with closed systems of vertebrates.1.4 Compare the efficiencies of hearts with one, two, three, and four chambers.

1.5 Describe the blood circulation pattern and vessels in the mammalian systems.

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There are three specific types of blood vessels that are used in moving blood through our circulatory system, based on size, which ones carry blood to the

heart and which ones carry blood away form the heart?What do capillaries do?

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VESSELS THAT MAKE UP THE CIRCULATORY SYSTEM

Arteries: carry oxygenated blood away from the heart.

Veins: carry deoxygenated blood to the heart.

Capillary Beds: diffusion of oxygen into cells and carbon dioxide out of cells; plus food and wastes.

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Structure of the Heart and Names of Blood Vessels:1. Atria: thin-walled chamber of the hearta) left atrium: receives oxygenated blood from the lungs via the pulmonary veinsb) right atrium: receives de-oxygenated blood from the body via the vena cava

2. Atrioventricular (A.V.) valves:  - located between each atrium and ventricle,    - prevent backflow of blood from ventricle to atriuma) bicuspid valve: between left atrium and ventricleb) tricuspid valve: between right atrium and ventricle

3. Ventricles: muscular chamber responsible for pumping blooda) left ventricle: pumps oxygenated blood to body via aortab) right ventricle: pumps de-oxygenated blood to lungs via pulmonary ateries

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Structure of the Heart and Names of Blood Vessels Continued...4. Septum: wall of muscle separating the 2 ventricles

5. Pulmonary Arteries (left and right): carry de-oxygenated blood from heart (r.v.) to lungs ***only arteries that carry de-oxygenated blood***

6. Pulmonary Veins (left and right): carry oxygenated blood from lungs to heart (l.a.) ***only veins that carry oxygenated blood***

7. Aorta: the largest artery in the body, carries oxygenated blood from the heart (l.v.) to body

8. Vena Cava: carries de-oxygenated blood back to heart (r.a.)a) superior vena cava, comes from headb) inferior vena cava, comes from the rest of the body

9. Semilunar Valves: found where blood vessels attach to the heart in each ventricle, prevent back flow of blood into ventricles from veins

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1. to the Superior and Inferior Vena Cava,2. then to the Right Atrium3. through the Tricuspid Valve4. to the Right Ventricle5. to the Pulmonary Artery6. to the Lungs

Blood From the Body Flows:

1. to the Pulmonary Veins2. to the Left Atrium3. through the bicuspid valve4. to the Left Ventricle 5. through the Aortic Valve6. to the Aorta7. to the body

The Blood Picks up Oxygen in the Lungs, and then Flows from the Lungs:

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HEART

(to lungs)

(from lungs)

(body vein from body)

(to body arteries)

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Review...1. What is the main difference between the right and left atrium?

2. What structures are used to allow oxygen to diffuse into our body cells and carbon dioxide to diffuse out of our body cells?

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2. Explain the functioning of the human circulation system.

2.1 Describe the functions of the heart, lungs, kidneys, and liver in the circulation system.2.2 Describe the ABO and Rh typing systems for human blood.

2.3 Consider the role of the blood in the immune system and the effect of the human.2.4 Research the use of artificial hearts, heart transplants, and circulation machines used during open-heart surgery.2.5 Discuss respiration by relating the activity to the physical structure like the lungs and blood and the cells fed by the blood.

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BLOOD COMPONENTSBlood is composed of cells and other substances suspended in plasma.Plasma: a clear, straw-colored liquid that is 90% water and 10% dissolved substances that include vitamins, enzymes, hormones, food, and respiratory gases. 3 types of cells: red, white, and platelets (all madein the bone marrow)

Red Blood Cells: specialized for the transport of O2have no nucleus or other organelles and are filled with hemoglobinhemoglobin: contains iron and has a red pigment; picks up oxygen in the lungs to deliver to body cells to help with respiration only survive 110-120 days because they experience alot of wear and tearafter this time, they are removed from circulation and destroyed in the liver and spleen.the liver salvages iron ions from these cells and then cells in the bone marrow use this iron to make new red cells

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White Blood Cells:have a nucleusthey have no hemoglobin and are therfore colorlessthey are larger than red blood cells, there are less of them in the blood only survive about 10 daysthey can differ in size and function, but their main function is to destroy pathogens (e.g. bacteria) that invade your body.some aid in the repair of wounds

Platelets:they are only fragments of cellsthey are colorless and disk-shaped, and do not have nucleihave a lifespan of about four daystheir function is to aid in blood clotting

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BLOOD CLOTTING PROCESS

Platelets in bone marrow are released to blood cells. They stick to broken vessels, then stick to each other. The cells get trapped in the fibrin threads, thus building up a clot.

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Review...

1. What is the most important component of blood?Why?

2. What would happen if a person lacked platelets in their blood? Does anyone know what word is used to describe this condition?

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2. Explain the functioning of the human circulation system.2.1 Describe the functions of the heart, lungs, kidneys, and liver in the circulation system.2.2 Describe the ABO and Rh typing systems for human blood.

2.3 Consider the role of the blood in the immune system and the effect of the human.2.4 Research the use of artificial hearts, heart transplants, and circulation machines used during open-heart surgery.

2.5 Discuss respiration by relating the activity to the physical structure like the lungs and blood and the cells fed by the blood.

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First, what is immunity??Any ideas what a definition of immunity would be?

How might our blood help our body with immunity?

Immunity: the capacity of the human body to resist most pathogens that might damage tissues or organs

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The Body has Two Types of Immunity...

1. Nonspecific Protection and Inflammatory Process:this type involves intact skin and mucous membranesthe layers of skin covering the body and the layers of mucous membranes lining the digestive and respiratory tracts provide a protective barrier against invasionif the barrier is broken, substances in the circulating blood initiate an inflammatory responsethis means that injured cells release a chemical called histaminethis chemical causes nearby capillaries to swell and become "leaky"then, various types of white blood cells pass through the capillary walls and gather at the site of the injury

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Two New Words...

antigens: any foreign substance (e.g. bacteria, virus, fungus) that can stimulate the production of antibodies and that can combine specifically with them

antibodies: a protein molecule produce by the immune system that is capable of binding with antigens in order to "disable" them and provide immunity

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2. Specific Immune Response:carried out by small, white blood cells called lymphocytesthey are specialized so that they recognize foreign substances (antigens)Three types of lymphocytes:a) B cells - found in the bone marrow  - their function is to produce antibodies to act against   antigens in our body - memory B cells and antibodies also exist to recognize antigens that   have previously infected the body

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b) T cells - found in the thymus gland  - four types of T cells i) killer T cells: attack infected cells ii) helper T cells: help B cells make antibodies iii) memory T cells: help remember antigens that have previously    infect the body  iv) suppressor T cells: used to release a chemical when an infection  is over so that B and T cells stop being producedc) Macrophage - it engulfs pathogens, via phagocytosis, and disassembles them

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How do all 3 of these cells work together in an "attack?"1. Identification of the Antigen = helper T cells (building the army): - have special receptors that can detect when a B cell has started   producing antibodies - this leads to a chemical being released that causes production of   more macrophages, killer and suppressor T cells being produced2. Attack from the B cells and macrophage: - antibodies of B cells attach to antigens (using the lock and key   method) - after attachment, the antibodies begin to multiply, and make   clusters of antibodies and antigens - macrophage can then engulf and destroy cluster of antigens3. Attack from killer T cells: - infected body cells displays an antigen that the killer T cell   recognizes - bores holes into the infected cell membrane (cell bursts)

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4. Suppressor T cells - after an attack is over, suppressor T cells release chemical to shut off   B and T cell production5. Memory B and T cells - memory B and T cells are formed during the battle that contain a   specific antibody that is then stored in the spleen, if body is exposed  a second time to the same antigen, memory B cells release many   antibodies so that the pathogen is killed before symptoms occur

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Flow chart of a Specific Immune Response...

1. Detection and production

2. Attack from B cells

3. Attack from T cells

4. Suppressor T cells

5. Memory B and T cells

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Review...

1. What are the three types of lymphocytes and what are their main function?

2. What is the main connection between blood and our immune system?

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2. Explain the functioning of the human circulation system.2.1 Describe the functions of the heart, lungs, kidneys, and liver in the circulation system.

2.2 Describe the ABO and Rh typing systems for human blood.2.3 Consider the role of the blood in the immune system and the effect of the human.

2.4 Research the use of artificial hearts, heart transplants, and circulation machines used during open-heart surgery.2.5 Discuss respiration by relating the activity to the physical structure like the lungs and blood and the cells fed by the blood.

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Problems with the Immune Response:1. Human Immunodeficiency Virus (HIV): - HIV primarily infects the T cells of the immune system. - the virus attaches itself to a host, T cell - inside the host cell, the viral RNA is copied and becomes a part of a cell's DNA - each infected cell then becomes a factory for the production of HIV - when the host cell ruptures, hundreds of viruses are released - reproduction of HIV in T cells leads to a gradual decline in the   number of T cells, weakened function of the immune system, and   increased susceptibility to infections and cancers.2. Organ transplant rejections: - rejection occurs by T cells - these cells identify the planted organs as foreign and invade the tissue   - to prevent this from happening, drugs are used to suppress the immune system, but   this leaves the patient vulnerable to other infections

http://www.youtube.com/watch?v=U2h0ECyMWhE

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ABO Blood Typing and its Effect on the Immune Systemsome of the blood group systems can cause problem under certain circumstancesthe blood types that arise from the ABO blood group are not always compatiblethis incompatibility comes about because antibodies in the plasma of one blood type (type A) react with antigens on the red blood cells of another blood type (type B)this reactions causes clumpingtherefore, transfusing blood of one type into blood of another type can be fatal

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ABO blood groups and Rh antigensRh antigens:In some humans, there are what are called Rh antigens found on the surface of red blood cells.An Rh positive individual HAS these Rh antigens on their red blood cells, and an Rh negative person DOES NOT.Usually, antibodies to these Rh antigens are not present in the blood plasma. However, antibodies will develop if Rh positive blood is transfused in an Rh negative individual or if an Rh negative woman delivers an Rh positive baby. When either of the conditions mentioned above occurs, antibodies to these Rh antigens develop, and the result is that red blood cells are destroyedIn the case of the Rh negative woman, there is no danger in the first pregnancy, but in the 2nd pregnancy, some of the Rh antibodies could transfer into the fetal blood and cause the red blood cells to be destroyed.

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In-Class Assignment...- Once you have finished answering the questions on your sheet, please read pages 171-? and find out what problems occur in a person's immune system in order to develop allergies or autoimmune disorders.

- Please write a 3-4 sentence paragraph explaining each problem

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Review...

1. What are two potential problems people could have with their immune systems?

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2. Explain the functioning of the human circulation system.2.1 Describe the functions of the heart, lungs, kidneys, and liver in the circulation system.2.2 Describe the ABO and Rh typing systems for human blood.2.3 Consider the role of the blood in the immune system and the effect of the human.2.4 Research the use of artificial hearts, heart transplants, and circulation machines used during open-heart surgery.

2.5 Discuss respiration by relating the activity to the physical structure like the lungs and blood and the cells fed by the blood.

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Respiratory System

Definition: responsible for exchange of O2 and CO2 in the human body

Respiration is divided into 2 steps:1. Breathing: - external respiration - the exchange of gases between the atmosphere and the body (?)

2. Respiration: - internal respiration - the exchange of gases between the blood and the body's cells   themselves

The PHARYNX (throat) collects incoming air from the nose and mouth and passes it downward to the trachea (windpipe).

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Parts of the Respiratory System:

a) Nose and Nasal Passages:

The NOSE is the preferred entrance for outside air into the respiratory system. The hairs that line the wall are part of the air-cleaning system, they helps to screen out dirt and foreign particles. Nose also moistens and warms the air.

Air also enters through the MOUTH.

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The EPIGLOTTIS is a flap of tissue that guards the entrance to the trachea, closing when anything is swallowed that should go into the esophagus and stomach.

b) The TRACHEA (windpipe) is the nasal passage leading to the lungs via the pharynx and larynx. Lined with cilia and mucus to remove dirt and foreign particles.

Parts of the Respiratory System

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c) Bronchi, Bronchioles, Alveoli

The trachea divides into two branches called BRONCHI, which extend into each lung.

Each bronchus subdivides into many smaller tubes called BRONCHIOLES which end in cluster of air sacks called ALVEOLI.

Alveoli exchange gases between the air and the blood.

Each alveolus is surrounded by capillaries and is only 1 cell thick to promote diffusion. While in the capillaries, the blood gives off carbon dioxide through the capillary wall into the alveoli and takes up oxygen from the air in the alveoli.

Alveoli make of most of the sponge-like lung tissue.

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d) LungsComposed of the bronchi, bronchioles, and alveoli.Together with the heart, the lung occupies the thoracic cavity.The lung and heart are covered by a membrane which secretes a mucous coating to lubricate the lungs.

e) Diaphragm

The DIAPHRAGM is the strong wall of muscle that separates the chest cavity from the abdominal cavity. By moving downward, it creates suction in the chest to draw in air and expand the lungs.

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3. Describe the functions and functioning of nervous systems.3.1 Describe the structure of a neuron.3.2 Explain how neurons transmit impulses within and between themselves.

3.3 Compare the complexity of nervous systems in the planaria, earthworm, and human.3.4 Contrast the functions of the central nervous system and the peripheral nervous system in humans.3.5 Compare the structure of the brains of reptiles and humans.

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Types of Nervous Systems...

All animals have a nervous system. Its degree of complexity depends upon the complexity of the animal.

Flatworms:- have a fairly complex system for a worm- there nervous system is made up of 2 nerve cords (called transverse and longitudinal nerves) that extend along the length of its body.- at the anterior end, there is a mass of nerve tissue called a ganglion (similar to a brain, a center where nerve impulses are exchanged)

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Types of Nervous Systems...

Earthworms:- have well developed nervous systems- a main nerve cord extends along the ventral (bottom) side of the body- many ganglia occur along the nerve cord- a large ganglion (brain) is found at the anterior end of the body

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Types of Nervous Systems...

Humans:- chordates (that's us!) have a dorsally (top) located nerve cord

- this cord is surround by bone (vertebrae) and the anterior end of the nerve cord is enlarged (brain) and is the dominant controller of the whole nervous system

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Organization of the Nervous System

1. Central Nervous System (CNS)

Brain and spinal cordActs as a coordinating center for all incoming and outgoing informationConnected to the rest of the body by nerves that make up the peripheral nervous systemSpeaking and walking are controlled by the CNS

In vertebrates, the nervous system is quite complex. Therefore, it is divided into 2 parts that differ in their functions.

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Peripheral Nervous SystemComposed of sensory neurons and motor neuronsI. Sensory NeuronsCarry nerve impulses from sense organs and receptors to CNSII. Motor NeuronsCarry nerve impulses from CNS to muscles and glandsFurther subdivided into: - Somatic nervous system:   contains sensory and motor nerves of skin, skeletal, muscle,   and bone = voluntary - Autonomic nervous system:  motor nerves which control internal organs = involuntary (e.g. controls the   heart, smooth muscles)  divided into the sympathetic (prepares the body for emergencies) and   parasympathetic (counteracts the sympathetic nervous system; slows the   heartbeat down) nervous systems

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3. Describe the functions and functioning of nervous systems.

3.1 Describe the structure of a neuron.3.2 Explain how neurons transmit impulses within and between themselves.3.3 Compare the complexity of nervous systems in the planaria, earthworm, and human.

3.4 Contrast the functions of the central nervous system and the peripheral nervous system in humans.3.5 Compare the structure of the brains of reptiles and humans.

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Nervous System3 Elements of the Nervous System:1. Receptors: any organ that picks up stimulus (i.e. eyes, noes, skin, ears)

2. Effectors: any organ that reacts to a stimulus (i.e. muscle, gland)

3. Conductors: transmit information about stimuli between the receptor and an effector (i.e. neurons, including the brain and spinal cord)

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What are Neurons?- are the building blocks of all nervous systems, most nerves are composed of many neurons- transmit impulses. These nerve impulses are actually small electrical currents passing from neuron to neuron, sending messages to and from the brain and bodyMade up of several parts:1. Dendrite: connects nerve to nerve, carries nerve impulses towards the cell body, made up of cytoplasm

2. Cell Body: area of the nerve containing the nucleus

3. Myelin Sheath: is the fatty covering over the axon of a nerve cell, to speed the rate of impulse. Acts as insulators for the neurons.

4. Axon: area of the cytoplasm that carries nerve impulses away from the cell body to other nerves or effectors

5. Synapse: the region over which an impulse passe

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How the Nervous System Works:Neurons do not touch one another, there is a space (SYNAPSE) between neurons

Synapses contain a chemical (neurotransmitter: acetylcholine) that passes the impulse from neuron to neuron

synapses are capable of transmitting impulses in one direction only

the process then of transmitting impulses is like a chain reaction, made possible by sodium and potassium ions

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How the Nervous System WorksProcess of transmitting impulses:In a resting nerve cell, there is normally more potassium ions inside of the cell and more sodium ions outside of the cell (due to the protein pump); however, when an impulse is received by the dendrite of a nerve cell:1. part of the cell membrane becomes more permeable to sodium ions.

2. As a result, sodium ions rush into the neuron, causing the electrical charge of the neuron to suddenly change and, forcing potassium ions to diffuse out of the nerve cell.

3. This movement of sodium into the cell and potassium out of the cell, causes a chain reaction, which moves the impulse along the entire length of the neuron.

5. Once the impulse reaches the end of the neuron, the neurotransmitter then carries the impulse to the next neuron.

6. This continues until the message reaches the desired effector.

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Movement of an impulse down a nerve cell...

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3 Types of Neurons

1. Sensory Neurons: receive information from the internal and external environment; transmit impulses towards the brain or spinal cord

2. Interneurons: transmit impulses from one neuron to another

3. Motor Neurons: transmit impulses from brain or spinal cord to an effector--a muscle of a gland

These 3 neurons, combined with the receptor, which detects impulses, and the effector, which acts upon the impulse makes up the REFLEX ARC.

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Reflex Arc1. Sensory neurons (receptor) in the ear hear the ringing of the phone.2. Sensory neurons transmit this message to interneurons (how??) and then to motor neurons.3. Motor neurons cause muscles in your hand to contract andpick up the phone.4. Some neurons may synapse to your brain (making it aware that the ring of the phone is loud) and may result in a secondary response of plugging your ears because that is a loud ring!

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Review...

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3. Describe the functions and functioning of nervous systems.3.1 Describe the structure of a neuron.3.2 Explain how neurons transmit impulses within and between themselves.3.3 Compare the complexity of nervous systems in the planaria, earthworm, and human.

3.4 Contrast the functions of the central nervous system and the peripheral nervous system in humans.3.5 Compare the structure of the brains of reptiles and humans.

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The Brain, a Part of the Central Nervous System

- is the control center of an animal's body; is found at the anterior end of the body, at the end of the nerve cord

- is made up of a large cluster of neurons, which, together, make up an organ capable of thinking, reacting, and running a body

- endorphins (natural painkillers produced by the brain) block the pain receptor sites in the brain, reducing the intensity of the pain

- the brain is divided into 2 hemispheres (halves) a) right hemisphere, controls the left side of the body b) left hemisphere, controls the right side of the body

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The Brain has Four Lobes...

1. Frontal lobe: controls voluntary muscle movement and intellectual activities

2. Temporal lobe: vision, hearing, memory, and interpretation

3. Parietal lobe: touch temperature, emotions, and speech interpretation

4. Occipital lobe: vision and the interpretation of visual information

Frontal

Temporal

Occipital

Parietal

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All brains have a common set of parts:

1. Olfactory bulbs: interprets and registers smell2. Cerebrum:thinking and interpreting part of the brain 3. Cerebellum:essential for coordination of movement4. Optic Lobe:interprets and registers sight5. Pituitary:controls hormone functions

6. Medulla Oblongata:hind brain; transmits impulses7. Thalamusinterprets sensory information8. Corpus Callosumallows communication between the two hemispheres of the brain9. PonsRelays information between the peripheral and central nervous systems10. Hypothalamus:link to the endocrine system; controls the pituitary gland

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Parts of the Brain, Excluding the Olfactory Bulb and the Optic Lobe

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Comparison of Vertebrate Brains...

- If you were to examine other vertebrate brains (besides the human one we have just learned about) you would identify many of the same structures just discussed; however, some of these structures would be reduced or enlarged in size depending on the specific function the vertebrate needs their brain to carry out.

- For example, in fish, amphibians, reptiles, and birds, the optic lobes (vision center) are large because these animal require keen eyesight. Although vision is important in mammals, the optic lobes are not as large.

- There are other adaptations, too. We are going to read and answer questions about these adaptations in order to compare several different vertebrate brains.

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4. Explain how the human endocrine system influences body development and maintenance.

4.1 Describe the general structure of hormones.4.2 Describe the influence of the pituitary gland on body processes and on other glands.

4.3 Discuss the relationship between insulin and the body’s control of blood sugar levels in the two forms of diabetes.4.4 Outline the functions of hormones produced by several other glands.

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Endocrine System

The endocrine system is a series of glands that secrete hormones which: - regulate all the body's functions. It controls the rate of growth, feelings   of hunger, body temperature, how much fluid we have in our bodies   and much more. - regulate physical and mental development - control chemical reactions - affect maturity and reproduction

Definition of a Hormone: is an informational molecule that is synthesized by cells called endocrine cells.

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Two Types of Hormones...Steroid Hormones:include both male and female sex hormonesmade of complex rings of C, H and O moleculesare fat soluble moleculesthese molecules move directly into the fluid between cells, then into cellsonce inside of a cell, they combine with receptor molecules in the cytoplasm and then move in to the nucleusin the nucleus, the molecules match with a like strand of a chromatid and a message is sent to the RNA to begin the production of specific protein (control protein synthesis)

Protein Based Hormones:include insulin, growth hormone, epinephrineare made of long chains of amino acids and are soluble in water

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Hypothalamus and the Pituitary Gland--Important Endocrine Glands...

One of the most important endocrine glands is the pituitary, which secretes hormones that control the rate at which several other endocrine glands (including the thyroid and adrenal glands) function. The pituitary gland consists of 2 parts (the anterior and the posterior pituitary glands) which lie at the base of the brainThe posterior pituitary is connected by means of a stalk to the hypothalamus. The hypothalamus controls the pituitary through a negative-feedback system: - change is detected by receptors - receptors trigger release of a certain hormone to target specific cells of pituitary   gland to release certain hormones - when balance is reached, receptors trigger release of a different hormone to inhibit   the original hormone released

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Posterior Pituitary: releases 2 main hormonesa) antidiuretic hormone (ADH): it promotes the reabsorption of water in the kidneys. When it is detected that the blood lack water, ADH is produced. When the water level returns to normal, ADH production ceases.

b) oxytocin: causes the uterus to contract and can be used to artificially induce labor. It can also be used to stimulate the release of milk from the breast when a baby is nursing.

Anterior Pituitary: it produces at least 6 different hormones, we'll discuss two of them:a) Growth hormone (GH): it determines the size of an individual. If a problem occurs, it results in dwarfs or giants.

b) Lactogenic hormone (LTH): is produced in large amounts after childbirth. It causes the mammary glands to develop and produce milk.

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How does the Hypothalamus regulate growth in the body?

1. Receptors in the liver send a message to hypothalamus regarding the need for growth

2. In response, the hypothalamus puts out growth hormones releasing factor which affects the pituitary gland.

2. The pituitary releases the growth hormone into the blood stream.

3. The growth hormone target is in the liver, this is where the hormone travels to.

4. Once inside of the liver cells, the liver secretes hormones called somatomedins which go to receptors on bones, muscles and connective tissue and cause an increase of growth.

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Review...

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4. Explain how the human endocrine system influences body development and maintenance.4.1 Describe the general structure of hormones.

4.2 Describe the influence of the pituitary gland on body processes and on other glands.4.3 Discuss the relationship between insulin and the body’s control of blood sugar levels in the two forms of diabetes.

4.4 Outline the functions of hormones produced by several other glands.

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Hormones Produced by Other Endocrine Glands...

Pineal Gland:Location: in the brain (posterior to the pituitary and hypothalamus)Hormone Produced: melatoninFunction: regulates circadian rhythms (day/night cycles)

Thyroid:Location: base of the neckHormone Produced: thyroxineFunction: regulates the rate of cellular respiration in the body

Parathyroid:Location: back of the thyroid glandHormone Produced: parathyroid hormone (PTH)Function: controls the metabolism of calcium in the body necessary for healthy bones, teeth, and tissues

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Thymus:Location: upper chestHormone Produced: thymosinFunction: controls the growth of certain white blood cells that help the body fight infection

Adrenal Glands:Location: top of each kidneyHormone Produced: epinephrine (adrenaline) and nor-epinephrine (nor-adrenaline) Function: creates increased energy and aggressiveness in individuals

Pancreas:Location: abdomenHormone Produced: insulin and glucagonFunction: controls blood glucose levels

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Gonads:Location: lower abdominal cavity or groinHormones Produced: males - testosterone  females - estrogen and progesteroneFunction: testosterone: causes genitals to mature, sperm production,   hair growth, and deepening of the voice  estrogen: causes genitals to mature, breast and hip   development, beginning of menstrual cycle  progesterone: regulates pregnancy and child bearing

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Review...

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4. Explain how the human endocrine system influences body development and maintenance.4.1 Describe the general structure of hormones.4.2 Describe the influence of the pituitary gland on body processes and on other glands.

4.3 Discuss the relationship between insulin and the body’s control of blood sugar levels in the two forms of diabetes.4.4 Outline the functions of hormones produced by several other glands.

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Control of Blood Glucose (Sugar) Levels

**Remember: the pancreas produces two hormones: insulin and glucagon**These two hormones are the primary regulators of blood glucose levels.

Scenario one: Low levels of blood glucose:Low levels of blood glucose provide feedback to the pancreas, which causes its cells to produce more glucagon. Glucagon then increases the conversion of glycogen to glucose in the muscles and liver, thus increasing blood glucose levels.

Scenario two: High levels of blood glucose:High levels of blood glucose provide feedback to the pancreas, which causes its cells to produce more insulin. Insulin then causes the uptake of glucose, by muscle and liver cells, thus decreasing blood glucose levels.

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Insulin and Glucagon

have opposite effects on controlling the levels of glucose in the blood

After a meal, glucose levels rise. As a result, insulin secretions increase and glucagon secretions decrease.

On the other hand, during fasting, insulin secretions decrease and glucagon secretions increase.

Maintaining an appropriate glucose level is crucial. If not, there are several problems that can occur...one of these is diabetes.

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Type 1 DiabetesA genetic disorder associated with inadequate production of insulin. These individuals are insulin-dependent.

Symptoms:- blood sugar levels rise sharply following meals (known as hyperglycemia)- kidney is unable to reabsorb all the glucose that filters through it, therefore large amounts of glucose appear in the urine- excretion of glucose draws water out of body through osmosis, therefore large amounts of urine are produced and individual is very thirsty- low energy levels (since there is no uptake of glucose, cells soon become starved for glucose and must turn to other sources for energy, such as fats and carbohydrates, which are not as energy- rich as glucose) 

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Type II Diabetes

This form of diabetes occurs because the body becomes resistant to insulin. In these cases, insulin is still produced, but the body does not respond to the effects of insulin as it should. This is called insulin resistance.

90% of people who have diabetes have type II and this is partially due to the rise in obesity, which is one factor that can contribute to the body becoming insulin-resistant.

Individuals with type II diabetes will experience the same symptoms as those with type I diabetes, but many of their symptoms can be managed through proper diet and exercise, and, in some cases, insulin shots may not be required at all.