Introduction toAnimal Systems

Tissues, Homeostasis, & Nutrition

Major Theme

How organisms obtain, process*, and use their energy resources.

1. Anatomy – structure2. Physiology – function

- structure is related to functiona. by analyzing structure you can tell what it doesb. the best structure to fit the function will be naturally

selected from the many available options of a varying population

3. Hierarchical levels of organizationcells tissue organ organ system

a. tissue – groups of cells with a common structure and function

(study of tissue – histology)4 Types of tissues1. Epithelial2. Connective3. Nervous4. Muscle

1. Epithelial tissue – sheet of tightly packed cellsa. Covers outside of body

- protection from mechanical/chemical injury, microorganisms, & water loss

- sensation – many sensory nerve endings found in this tissueb. Lines organs/glands

- absorption of nutrients- secretion of enzymes/hormones- excretion of waste material- diffusion of chemical gases (lungs, capillaries)- reduces friction

2 Structural criteria for classifying epithelia tissue1. # of cell layers

- simple epithelium – single layer of cells- stratified epithelium – multiple layers of cells

(found where wear & tear occurs)

2. Shape of surface cells- cuboidal – cube (dice-shaped)- columnar – brick shaped- squamous – flat like floor tiles

2. Connective Tissue – sparsely scattered cells in an extracellular matrix(matrix consists of a web of fibers embedded in substances secreted by the cells of the tissue)

a. Fibers bind and support other tissues3 kinds of Fibers

a. Collagenous – made of collagen (very abundant protein)

- non-elastic- don’t tear easily when pulled lengthwise(keeps flesh from tearing away from bone

when pinched/pulled)b. Elastic – made of elastin

-rubbery- restores your skin to its original shape when pinched or pulled

c. Reticular – made of collagen as well- continuous with collagenous fibers- joins connective tissue to adjacent tissues

6 Major Types of Connective Tissue in Vertebrates1. Loose connective tissue2. Fibrous connective tissue3. Adipose tissue4. Cartilage5. Bone6. Blood

Loose Connective Tissue- Most widespread connective tissue in vertebrates containing all 3 fiber

types

Functions- binds epithelia to underlying tissues- holds organs in place

Specialized cells1. Fibroblasts – secretion of protein2. Macrophages – engulf foreign particles through phagocytosis

Adipose Tissue- Specialized form of loose connective tissue that stores fat in adipose cells

Functions- Pads & insulates the body- Stores energy as fat molecules (fat droplet in cell swells when fat is stored)

Fibrous Connective Tissue

- Made of densely packed collagenous fibers

Function- maximizes non-elastic strength for tendons and ligaments

tendons – attach muscles to bonesligaments – join bones together at joints

Cartilage- Made up of an abundance of

collagenous fibers embedded in a rubbery matrix of chondroitin sulfate

Functions- strong & flexible support material (nose, ears, rings of windpipe, discs that cushion our vertebrae, & caps on the ends of some bones)

Specialized cells1. Chondrocyte cells – secrete chondroitin sulfate and collagen

Bone

- A mineralized connective tissue- The microscopic view of hard mammalian bone consists of repeating units

called osteons, which consist of concentric layers of mineralized matrix (Slide 7)

Function- support the bodies of most vertebrates

Specialized cells1. Osteoblasts – deposit a matrix of collagen

Calcium, Magnesium, & Phosphate ions combine with this matrix & harden to form mineral hydroxyapatite

Blood

- Unusual connective tissue whose extracellular matrix is called plasma, which contains water, salts, and dissolved proteins

Functions & Specialized Cells- Red blood cells - carry oxygen- White blood cells - fight viruses, bacteria, and other invaders- Platelets - aid in blood clotting

3. Nervous Tissue – tissue of the nervous systema. Senses stimuli and transmits signals from one part of the animal to the otherb. nerve cells – aka neurons transmits nerve impulses

- made up of a cell body, dendrites, & axons

4. Muscle Tissue – made up of long cells called muscle fibers that are capable of contracting when stimulated by nerve impulses

a. Muscle fibers contain myofibrils made of contractile proteins1. actin2. myosin

b. This tissue is most abundant and most energy in the active animal is used for contraction of muscle tissue

3 kinds of Muscle Tissue1. Skeletal aka Striated – voluntary movement of body2. Cardiac – (involuntary & striated) forms contractile wall

of the heart3. Smooth – (involuntary)

-no striations-found in walls of the digestive tract, urinary

bladder, arteries, and other internal organs

Homeostasis

Homeostasis – the body’s automatic tendency to maintain a near constant internal environment

Internal Components of Homeostasis:1. O2 & CO2 concentrations

2. pH 3. Nutrient & Waste product concentrations4. Salt & other electrolyte concentrations5. Volume & pressure of extracellular fluid

Control Systems2 Components

1. sensor – senses stimuli & sends message to effector2. effector – responds to the message by causing a change

Negative Feedback Control – (used by most body systems) feedback causes a reverse of the response

Ex. – Body temperature begins to increase sweat glands produce sweat decreases body temperature to homeostatic temp.

Positive Feedback Control – feedback increases or amplifies the responseEx. – Pressure on uterus causes increase in contractions

stimulates Oxytocin (hormone) increases strength & frequency of contractions

(examples on board)

Animal Nutrition

Essential Nutrients – organism cannot manufacture

1. Essential Amino Acids (protein)- approximately 10 - sources: meat, eggs, cheese, balanced plant diet (Fig 41.4)- organic (contain C)

2. Essential Fatty Acids (Fats)*Phospholipids (cell membrane)- organic

ex. – linoleic acid

Animal Nutrition

3. Vitamins- organic 1. Water-soluble (dissolve in H2O)

- vit B & derivatives (B1, B2, B6, B12) – coenzymes- vit C – produce connective tissue

2. Fat-soluble (dissove in fats)- A – eye pigment- D – Calcium absorption- E – anti-oxidants – oxidation -> free radicals -> cell damage- K – blood clotting

4. Minerals- inorganic (no C)- Ca, P, Fe, Zn, Mg, Na, K, Cl

Obtainment of Food

Food Type (Heterotrophs)1. Herbivore – eats autotrophs (make food (glucose))2. Carnivore – eats other heterotrophs (get food from outside source)3. Omnivore – eats both

Feeding Mechanism1. Suspension – sift food particles from H2O

ex. Clam, oyster2. Substrate – live on/in your food source

ex. Tapeworm, maggot 3. Fluid – suck nutrient-rich fluid from host

ex. Hummingbird, mosquito, leech4. Bulk – eat large pieces/amounts of food

ex. Crocodile, alligator