Chapter 33

Animal Organization and Homeostasis

33.1 Types of TissuesA tissue is composed of specialized cells of the same type that perform a common function four main types:

epithelial tissue: covers and lines connective tissue: binds and supports muscular tissue: contracts (moves) nervous tissue: receives and transmits nerve

impulses remember that cells form tissues, tissues

form organs, and organs form organ systems

33.1 Types of Tissues epithelial tissue

covers and lines parts (sheets of cells) tightly packed form a continuous layer

attached to basement membrane classified on the basis of:

number of layers of cells simple = one layer stratified = multiple layers pseudostratified = one layer with

appearance of multiple layers shape of cells

cuboidal, columnar, squamous (flat)

33.1 Types of Tissues epithelial tissue, cont.

simple epithelia squamous

single layer of flat cells lines parts (ex: blood vessels, lungs) exchanges materials

Nucleus

BasementMembrane

Lumen

Nucleus

33.1 Types of Tissues epithelial tissue, cont.

simple epithelia, cont. cuboidal

cube shaped cells found in glands, lines kidney tubules produce secretions lumen: tube in center where secretions

are released

BasementMembrane

Nucleus

33.1 Types of Tissues epithelial tissue, cont.

simple epithelia, cont. columnar

single layer of tall cells lines digestive system absorbs food microvilli: folds in the plasma membrane

to increase surface area

33.1 Types of Tissues epithelial tissue, cont.

simple epithelia, cont. pseudostratified

found in breathing passages (trachea) has cilia to move mucus to throat (mucus

traps foreign particles)

Cilia

Nucleus

BasementMembrane

33.1 Types of Tissues epithelial tissue, cont.

stratified epithelia squamous

many layers of flat cells outer layer of skin, lining of nose, mouth,

esophagus, anal canal, vagina protects

BasementMembrane

Nucleus

BasementMembrane

33.1 Types of Tissues epithelial tissue, cont.

stratified epithelia, cont. columnar

many layers of stretchy cells (transition from one shape to another)

found in urinary bladder stretches

33.1 Types of Tissues connective tissue

most abundant and widely distributed tissue in animals

diverse, but three common features: specialized cells (sparse) ground substance: noncellular substance

that separates cells protein fibers

collagen: flexible and strong reticular fibers: thin, branched collagen

fibers elastic fibers: contain elastin; weaker but

more elastic than collagen (ground + protein = extracellular matrix)?

Cell

Fiber

Matrix

33.1 Types of Tissues connective tissue, cont.

fibrous connective tissue loose fibrous connective tissue (areolar)

cells far apart; contains fibroblasts supports epithelium and internal organs allows lungs, arteries, bladder to expand protective covering over muscles, blood

vessels, nerves

Fat Storage Space

Nucleus

33.1 Types of Tissues connective tissue, cont.

fibrous connective tissue, cont. adipose tissue

energy reservoir (fat) insulates provides cushioning number of adipose cells is fixed

33.1 Types of Tissues connective tissue, cont.

fibrous connective tissue, cont. dense fibrous connective tissue

contains densely packed collagen fibers contains fibroblasts found in tendons (muscles to bones) found in ligaments (bones to bones)

Cell nucleiFibers

33.1 Types of Tissues connective tissue, cont.

supportive connective tissue cartilage

cells in small chambers called lacunae solid yet flexible support indirect blood supply slow healing

Matrix

Chondrocyte

33.1 Types of Tissues connective tissue, cont.

supportive connective tissue, cont. cartilage, cont.

hyaline cartilage: most common type; has very fine collagen fibers; nose, ends of long bones and ribs, rings in trachea

elastic cartilage: more elastic fibers; outer ear

fibrocartilage: strong collagen fibers; pads between vertebrae, knees joint

33.1 Types of Tissues connective tissue, cont.

bone most rigid connective tissue hard matrix of inorganic salts (esp. calcium

salts) deposited around protein fibers (esp. collagen fibers)

has blood vessels

MatrixBlood vessel

33.1 Types of Tissues connective tissue, cont.

bone, cont. two types:

compact bone makes up the shaft of a long bone

spongy bone is found at the end of a long bone; has irregularly shaped spaces; lighter than compact bone, but still strong

33.1 Types of Tissues connective tissue, cont.

fluid connective tissues blood: “formed elements” and plasma

plasma: liquid matrix red blood cells (RBC): more common;

carry oxygen; contain hemoglobin white blood cells (WBC): fight disease;

usually larger than RBCs platelets: clot blood; fragments of giant

cells found only in bone marrow lymph

located in lymphatic vessels helps fight infections, transport excess

fluids and solutes

RBC

WBC

Plasma Platelet

Striation

Nucleus

33.1 Types of Tissues muscular tissue

composed of cells called muscle fibers, which contain actin and myosin filaments

skeletal muscle (voluntary muscle) has many nuclei (due to large size) attached by tendons to bone voluntary: under conscious control striated (striped) in appearance

33.1 Types of Tissues muscular tissue, cont.

smooth (visceral) muscle no striations involuntary found in digestive system, blood vessels,

breathing passages, urinary bladder, uterus

Nucleus

33.1 Types of Tissues muscular tissue, cont.

cardiac muscle striated involuntary: not under conscious control found in the heart (pumps blood) single, centrally placed nucleus

Nucleus

Striation

33.1 Types of Tissues nervous tissue

Animal Bioenergetics energy Input (eat) digestion (hydrolysis) absorption catabolism

heat ATP

ATP used for cellular work, biosynthesis (anabolism)

Metabolic Ratetotal amount of energy used (kcal)/timefactors that influence: age, sex, size temperature: body and environment food—quality and quantity activities available oxygen hormone levels time of day

Endotherms generate body heat metabolically birds and mammals require more kcal/day than ectotherms most homeothermic (constant body temp.) Basal Metabolic Rate (BMR): endotherm’s

metabolic rate measure under resting, fasting and stress-free conditions

Ectotherms acquire most of their body heat from

environment body temperature and metabolic rate

changes with environmental temperature can only determine metabolic rate at a

specific temperature (called Standard metabolic rate)

uses less energy, can’t be active in cool conditions

Surface Area/Volume as size increases, surface area: volume

ratio decreases therefore, metabolic rate decreases with

size because heat loss decreases (hummingbirds and shrews)

large/complex animals have to have adaptations to increase surface area for absorption of oxygen/food

Functions of the BodyEnergy and Metabolism digestive system: provides raw materials respiratory system: exchanges gases circulatory system: carries materials to cellsHomeostasis urinary system: blood homeostasis thermoregulation: temperature

homeostasis immune system: kills things that might

prevent homeostasis

Functions of the BodyIntegration and Control endocrine system: long term with

chemicals nervous System: short term with electricity reponses and senses brain: integrates everythingContinuity of life reproductive systems development