Chapter 40 ~ An Introduction to Animal Structure and Function

Tissues : groups of cells with a common structure and function (4 types)

Anatomy : structure

Physiology : function

1- Epithelial: outside of body and lines organs and cavities; held together by tight junctions

basement membrane : dense mat of extracellular matrix

Simple: single layer of cells

Stratified: multiple tiers of cells

Cuboidal (like dice)

Columnar (like bricks on end)

Squamous (like floor tiles)

mucous membrane

Tissues, II

2- Connective: bind and support other tissues; scattered cells through matrix; 3 kinds:

A-Collagenous fibers (collagen protein) B-Elastic fibers (elastin protein) C-Reticular fibers (thin branched collagen fibers)

Loose connective tissue: binds epithelia to underlying tissue; holds organs

1-Fibroblasts- secretes extracellular proteins 2-Macrophages- amoeboid WBC’s; phagocytosis 3-Adipose tissue- fat storage; insulation

Fibrous connective tissue: parallel bundles of cells

1-Tendons- muscles to bones 2-Ligaments- bones to bones; joints (BOBOLI)

Cartilage : collagen in a rubbery matrix (chondroitin); flexible support

Bone : mineralized tissue by osteoblasts

Blood : liquid plasma matrix; erythrocytes (RBC’s) carry O 2 ; leukocytes (WBC’s) immunity

Tissues, III

3-Nervous : senses stimuli and transmits signals from 1 part of the animal to another

Neuron : functional unit that transmits impulses

Dendrites : transmit impulses from tips to rest of neuron

Axons : transmit impulses toward another neuron or effector

Tissues, IV

4- Muscle : capable of contracting when stimulated by nerve impulses; myofibrils composed of proteins actin and myosin; 3 types:

A- Skeletal: voluntary movement (striated)

B- Cardiac: contractile wall of heart (branched striated)

C- Smooth: involuntary activities (no striations)

Organ systems

Organ: organization of tissues

Mesentaries: suspension of organs (connective tissue)

Thoracic cavity (lungs and heart)

Abdominal cavity (intestines)

Diaphragm (respiration)

Organ systems…...

Digestive -food processing

Circulatory -internal distribution

Respiratory -gas exchange

Immune/Lymphatic -defense

Excretory -waste disposal; osmoregulation

Endocrine -coordination of body activities (chemical)

Reproductive -reproduction

Nervous -detection of stimuli/response (electrical)

Integumentary -protection

Skeletal -support; protection

Muscular -movement; locomotion

Exchange Points

Exchange points: locations in body where material

moves between body and environment or between compartments in the body.

Compartments

Intracellular

Extracellular: blood, interstitial fluid, cerebral/spinal fluid, ocular fluid, joint cavities

Internal regulation

Interstitial fluid : internal fluid environment of vertebrates; exchanges nutrients and wastes

Homeostasis : “steady state” or internal balance

Negative feedback : change in a physiological variable that is being monitored triggers a response that counteracts the initial fluctuation; i.e., body temperature

Positive feedback : physiological control mechanism in which a change in some variable triggers mechanisms that amplify the change; i.e., uterine contractions at childbirth

Metabolism : sum of all energy-requiring biochemical reactions

Catabolic processes of cellular respiration/digestion

Anabolic processes of protein synthesis/growth/development

Calorie; kilocalorie/C

Endotherms : bodies warmed by metabolic heat

Ectotherms : bodies warmed by environment

Basal Metabolic Rate (BMR): minimal rate powering basic functions of life (endotherms)

Standard Metabolic Rate (SMR): minimal rate powering basic functions of life (ectotherms)