BIo Exam 3 Study Guide

Movement and SupportEndoskeleton- series of levers in the body, muscles pull on them → movementHuman Skeleton

- Two Divisions- Axial Skeleton

- Cranium- Vertebral Skeleton- Rib Cage- Sternum- Sacrum- Coccyx

- Appendicular Skeleton- Hips and Shoulders- Limbs

- Vertebral (spinal) Column- 7 cervical vertebra

- Atlas (yes), allows head to move up and down- Axis (no), allows head to move side to side

- 12 Thoracic vertebra- Thoracic, more dense than cervical, lose mobility faster

- 5 Lumbar vertebra - Lumbar, DENSE, center of gravity, compressive force- Cartilage = compressed over time ---> back probs

- Sacrum - fused to form one bone- Coccyx (tail bone)

Joints- Ball and socket joint

- Almost 360 degree rotation- Hinge joint

- Almost 180 degrees of rotation- Knees, elbows

- Pivot joint- Lots of motion- Wrist, ankles, spine

- Immovable Joints- Pelvis, cranium- Move at youth so bain can grow help with birthing process- Eventually bones fuse at suture or immovable joints

Types of Bone- Flat bones

- Spongy bone only

- Shoulder, hip, sternum- Long Bones

- Dense- Handle forces (e.g. femur)- Spongy bone

- Red marrow - for making blood cells- Compact bone

- Yellow marrow - for fat storageAnatomy of a Long Bone

- Spongy bone, holes in bones = less heavy- Osteocytes = cells that make up bone- Compact bone = dense - Yellow Marrow = mostly fat

Bone is important for Ca++ regulation in the body- Calcium for muscle contraction

- Store calcium in bones- Osteoblasts (BUILD) deposit Ca++ in the bone - THICKENING AND REPAIRING

- Osteoblasts and Ca++ critical to healing of broken bones- Osteoclasts destroy bone to liberate Ca++

Interaction of Bones and Muscles- Bone → Bone = Ligament- Muscle → Bone = Tendon

Muscles- Antagonistic Pairs - muscles shorten, other muscles help pull because you can’t push

musclesThe Sarcomere

- Z line - Proteins come together- Myosin, thick with heads- Actin, thin helix, binding sites- Muscle contraction

- Z-lines get closer- Sliding filament theory- Interaction of actin and myosin depends on ATP- ATP necessary for contraction or relaxation of the muscle

Contraction of a Sarcomere 1. Impulse from a neuron (motor unit) → 2. Change in muscle cell membrane → 3. Calcium released into muscle cell (sarcoplasmic reticulum)4. Ca++ causes troponin + tropomyosin to move off the actin binding sites5. ATP attaches to myosin head → let go of actin binding sites6. ATP hydrolyzes + gives energy to myosin heads → 7. Shape change8. Myosin heads attach to actin binding sites

9. Shape change “POWER STROKE” pulls on actin10. Actin slides, moves Z lines closer together = CONTRACTION OF A SARCOMERE- Strength of contraction depends on number of motor units (neurons) activated and

number of sarcomeres activated- Not enough calcium, muscle won’t retract - Impulses from motor units increase in frequency and numbers to recruit more

sarcomeres - Too frequent = sustained (tetanic) contraction = no time to

relax → tetanus

NeuronsOrganization of the Nervous System

- 2 anatomical divisions- Central nervous system- Brain, spinal cord, process info- Peripheral nervous system- Deliver info to and from central

- 2 functional divisions- Sensory input- Collecting info- Motor output- Deliver info for action

- Somatic nervous system- Autonomic nervous system

- Parasympathetic- Calming, rest, digestion- Sympathetic- Fight or flight response

Components of Nervous System- Sensory neurons

- Collect info- Eyesight, skin, hearing

- Interneurons- Process info (integrate)- Brain, spinal cord

- Motor neurons- Action- Muscles that you can physically move

Components of a Neuron- ALWAYS travels in same direction- Dendrites- Receive info- Nerve cell body- Process info- Axon- Deliver info for action- Synaptic Knobs- Communicate with next cell

- Neurotransmitter- chemicals of communicationMyelin Aids Conduction

- Myelin sheath = fat layer- Keep signal in the axon → faster- Jump over nodes of ranvier

Neuron at Rest

- -70mV = Resting potential (ALWAYS neg)- Charge across membrane keeps nerve “readied”

- -40mV = threshold potential- Depolarization → repolarization = action potential

- Info going through axon- Neurons firing

- Stimulus → change in membrane → opens port and positive charges- Rest between firing = refractory period- Action potential is ALL OR NOTHING (hit -40 = action potential)- Control is by NUMBER of neurons firing or SPEED of firing

Synapse is key for neuron to neuron communication- Electrical synapse

- Rapid, one-to-one passing of an impulse- Really close together, pass action potential

- Chemical synapse- Uses neurotransmitter- Can recruit more neurons- Modulation of speed

Chemical Synapse- Common Neurotransmitters:

- Serotonin- well being, inhibitory- Dopamine- motor control, inhibitory- Norepinephrine- fight/flight, excitatory- Acetylcholine- motor neurons, excitatory- Anandamide- cannabinoid receptors

Modes of Drug Action- Agonist

- Increase effectiveness of neurotransmitter- Mimic - Inhibit breakdown - Inhibit reuptake (leave in synaptic gap)

- Antagonist- Decrease effectiveness of neurotransmitter- Block synthesis - Block packaging- Block release- Block binding sites

BloodPurpose of Blood

- Transport dissolved substances- Carry oxygen to cells for metabolism- Transport immune cells throughout body- Regulate body temp.

- Protect against vessel rupture- Regulate pH and water balance

Blood Components- 45% = Red Blood Cells

- Transport oxygen- No nucleus

Bags of hemoglobin- Less than 1% =

- White blood cells - Immune function- Entire cells

- Platelets- Clotting- Cell fragments

- 55% = Plasma- Extracellular matrix- 92% water- Proteins- Transporting

Formed Elements (cells or cell parts)- Flat bones → spongy → red marrow → blood stem cells- RBC = erythrocyte - WBC = leukocytes

- Immune system- Fight pathogens

- Platelets = Thrombocytes- Clotting- Cell fragments

How RBCs function- Shape = surface area- No nucleus, no organelles- Limited life span, replaced about 30 days- Full of hemoglobin

- Each hemoglobin = 4 oxygenErythropoietin (EPO) and Blood Doping

- Increases RBCs- Increases oxygen carrying capacity

Blood Types- ABO blood grouping and RH factors

- Proteins on surface of blood cells- How we type?

- Clumps/clotting = reaction, meaning the proteins are present- No reaction, no proteins present

Clotting Cascade

- Multiple steps = control- Platelets and clotting factors- Several steps of protein activation- Fibrin = contractile protein = sticky

- catch platelets + red blood cells = clotClots Go Bad

- DVT - Deep Vein Thrombosis - Clot break off and go to small vessels

- Pulmonary Embolism- Blood clot in lung

- Stroke- Heart attack

Cardiovascular System

Heart Parts- Body → Heart → Lungs → Heart → Body

deoxygenated pick up oxygen oxygenated- Arteris = AWAY- Veins = TO- BODY (right side, deoxygenated blood)

- Inferior and superior vena cava → right atrium → tricuspid valve → right ventricle → pulmonary semilunar valve → pulmonary arteries → LUNGS

- LUNGS (left ride, oxygenated blood)- Pulmonary veins → left atrium → bicuspid or mitral valve → left

ventricle → aortic semilunar valve → aorta → BODYCLOSED system

- 3 Basic Layers of Vessels- Inner = Smooth/Slick- Muscle = Resist pressure from heart- Outer = Connective tissue, adds strength

- Artery- ALWAYS AWAY from heart- Under pressure- High velocity- Lots of muscle

- Arteriole- Smaller arteries- Under pressure- Higher velocity- Thinner- Resistance

- Capillary- Business- Exchange between blood and tissues- Walls = 1 cell thick- Low pressure

- Venule- Low pressure- Low velocity- Valves- Rely on skeletal muscle to get blood back to the heart

- Vein- ALWAYS GO to heart- Large returning vessels- Have valves

Blood Pressure- Systolic (contraction of heart)- Diastolic (relaxation of heart)- Usually 120/80

Cardiac Control- Heart Rhythm- Heart muscle can initiate its own contraction- Electrical impulses from nervous system alter rate of contraction- SA Node = regulatory center

Sinoatrial node = pacemaker of heart- SA → AV → Bundle of His → Purkinje Fibers

ECG (Electronic Cardiogram)- P Wave

- Atria depolarize → Contract- QRS Complex

- Ventricles depolarize → spike → contract- T Wave

- Repolarizes → Rest