Animal Structure and Function (Outline)

1. Review levels of structural hierarchy of the living world 2. Define the terms anatomy and physiology. 3. Identify the four types of tissues in animals, their basic structure and function. 4. Learn the 4 types of epithelial cells with examples and their location and function. 5. Learn the importance of connective tissue, the different types and their function.

Compare and contrast cartilage, bone, tendons, and ligaments . 6. Learn the basic structure of muscle and the three different types and their

function. 7. Learn the structure of nerves and their function. 8. Define an organ and the organization of different tissues within. 9. Learn the 10 organs systems of the animal body, their overall functions, and

organs. 10.Compare and contrast early bodies of early animals with the three -layered large

complex animal bodies. 11.Recognize the importance of homeostasis for animals and review how warm

blooded organisms maintain their body temperature.

Atom

Molecules

Organelle

Cell

Tissue

Organ

Organ system

Organism

Population

Community

Ecosystem

Bioshpere

- Life is organized into a hierarchy of structural levels - Each level builds on the level below it (Emergence/ emergent properties)

Anatomy & Physiology

Rows of setae on a gecko’s foot

Spatulae coming from a single seta

Function: Walking on walls and ceilings by Salamander &

small lizards (Geckos) Structure: Hairs on toes (setae) are split into spatulae.

Molecules on spatulae adhere to solid surfaces.

Biological Theme: Structure fits function in the animal body

• Anatomy is the study of structure

• Physiology studies how structures function

Flight function depends on specific structures of wings, bone, and pectoral muscle

Palm

Finger 2 Finger 3

Shaft

Barb Barbule Hook

Feather structure

Wrist

Forearm

Finger 1

Internal bone structure

Shaft

Figure 20.1

Structure in the living world including that of animals is organized in a series of hierarchical levels

Muscle cell A Cellular level

B Tissue level Muscle tissue

C Organ level Heart

E Organism level Many organ systems functioning together

D Organ system level Circulatory system

Figure 20.2A–E

Structure in lab

Function in lab

Tissues are groups of many similar cells that perform the same specific function

Tissue types

• Epithelial tissue • Connective • Muscle • Nervous

http://www.bcb.uwc.ac.za/Sci_Ed/grade10/mammal/

Epithelial Tissue Structure: • Closely packed sheets of cells • Cover surfaces and line the cavities and tubes of

internal organs Functions:

• Protection • Exchange: Secretion, absorption • Excretion-waste products • Sensation

Flat

Cube-shaped

Column-shaped

Single layer on a basement membrane (connective tissue)

Multiple layers on a basement membrane (connective tissue)

Basement membrane (extracellular matrix)

Free surface of epithelium

Cell nuclei

A Simple squamous epithelium (lining the air sacs of the lung)

B Simple cuboidal epithelium (forming a tube in the kidney)

C Simple columnar epithelium (lining the intestine)

D Stratified squamous epithelium (lining the esophagus)

Layers of dead cells

Rapidly dividing epithelial cells

E Stratified squamous epithelium (human skin)

Colo

rized

SEM

Figure 20.4A–E

Underlying tissue

Simple Epithelium • Squamous

– mouth, blood vessels, heart, lungs and outer layers of the skin

• Cuboidal – Glands and their ducts, and the lining of the kidney tubules

• Columnar – lining of the stomach and intestines – Some specialized for sensory reception: nose, ears and

taste buds of the tongue

o Some ciliated for directing flow o Other glandular producing and secreting: enzymes, hormones, milk,

mucus, sweat, wax and saliva

• Stratified epithelium – Keratinized top layer (tough)- skin – Un-keratinized top layer- mouth cavity

• Epithelial tissue on the interior body surfaces is known as endothelium

Connective Tissue Structure • characterized by few cells in and large amount of

extracellular non-living matrix secreted by its cells – Liquid matrix (Blood) – Semi-solid matrix (Tendons & others) – Solid (Bone)

Functions • binds and supports other tissues • Movement • Many others

• Collagen o sponge-like scaffold of a tensil protein

• Cartilage o Specialized cells with extracellular matrix and proteins

(collagen and elastin)

• Bone o living and dead cells in the mineralized organic matrix ohardened by calcium phosphate and calcium carbonate

deposits

• Ligaments o connect bones to bone

• Tendons o connect muscle to bone

Cartilage- forming cells

B Fibrous connective tissue (forming a tendon)

Matrix

D Cartilage (at the end of a bone)

Central canal Matrix Bone- forming cells E Bone

F Blood

Elastic fibers

Collagen fiber

Cell

Collagen fibers

Cell nucleus

White blood cells

Red blood cell

Plasma

C Adipose tissue

Fat droplets

Figure 20.5A–F

B Fibrous connective tissue (forming a tendon)

A Loose connective tissue (under the skin)

Muscle Tissue Structure • Fibers made of many fused cells that have contractile

proteins and multiple nuclei • Three types of muscles

• Skeletal: voluntary body movements • Cardiac : pumps blood • Smooth: involuntary moves the walls of internal hollow

organs, such as the GI, arteries, bladder, uterus.

Function • Movement & mechanical work

Unit of muscle contraction Muscle

fiber

Nucleus

A Skeletal muscle

Nucleus

Muscle fiber Junction between

two cells

Muscle fiber Nucleus

C Smooth muscle

B Cardiac muscle

Figure 20.6A–C

Nervous Tissue Structure

• Neurons that make up the brain, spinal cord and peripheral nerves that branch throughout the body

• Branching neurons made of a cell body and have cell extensions: axon, and dendrites

Function • Communication network • Transmit nerve signals rapidly to control body

activities

Cell body Nucleus

Cell extensions

An organ is made of several tissues that collectively perform specific functions

Figure 20.9

Small intestine (cut open)

Lumen

Epithelial tissue (columnar epithelium)

Connective tissue

Smooth muscle tissue (2 layers)

Connective tissue Epithelial tissue

Lumen

Organ systems work together to perform life functions. Each organ system has one or more functions

Eleven organ systems: • Digestive • Respiratory • Circulatory • Immune • Excretory • Endocrine • Nervous • Integumentary • Skeletal • Muscular • Reproductive

The digestive and respiratory systems • Gather food and oxygen Gather oxygen • Digest & absorb Send oxygen to heart • Remove undigested food Remove carbon dioxide

A Digestive system

Mouth Esophagus

Liver Stomach Small intestine Large intestine

Anus

B Respiratory system

Nasal cavity Larynx Trachea

Bronchus

Lung

Figure 20.10A, B

The circulatory system and the lymphatic system

• Transports the food and oxygen • collect and circulate liquid to and from

tissues

The immune system • Protects the body from infection and

cancer

C Circulatory system

Heart

Blood vessels

E Lymphatic system

D Immune system

Bone marrow

Thymus

Spleen Lymph nodes

Lymph vessels

Figure 20.10C–E C Lymphatic system

The excretory system The endocrine and nervous systems

• Filters blood Control body functions • Disposes of certain wastes

F Excretory system

Kidney

Ureter Urinary bladder Urethra

Pituitary gland

Thymus Thyroid gland

Testis (male)

Adrenal gland Pancreas

G Endocrine system

Ovary (female)

The integumentary system Skeletal and muscular systems

Covers and protects the body Support and move the body

I Integumentary system

Hair

Skin

Nails

K Muscular system

Skeletal muscles

Cartilage

Bones

J Skeletal system

The Reproductive System • Production of gametes • Perpetuates the species

Figure 20.10L

Female

Vas deferens

Penis

Urethra

Testis

Prostate gland

Male

Oviduct Ovary Uterus

Vagina

L Reproductive systems

Figure 3.15

The Primordial Embryo

Animals exchange materials with their environment

Structural adaptation include shape and size: • Small with 2 layers for material exchange • Large with increased surface area and specialized structures

Small & simple body construction

Diffusion

Two cell layers

Diffusion

Mouth

Gastrovascular cavity Figure 20.12A

Larger & complex animals – specialized structures

that increase surface area – Exchange of materials

between blood and body cells via the interstitial fluid

Respiratory system

Excretory system

Digestive system

Circulatory system

External environment

Food Mouth

Animal

Body cells

Interstitial fluid

Anus Unabsorbed matter (feces)

Metabolic waste products (urine)

Intestine

Nutrients

CO2 O2

Figure 20.12B

The respiratory system with its enormous internal surface area

Figure 20.12C

Animals regulate their internal environment to achieve an internal steady state, homeostasis.

Homeostatic mechanisms

External environment

Internal environment

Small fluctuations

Large fluctuations Figure 20.13A

Figure 20.13B

Homeostasis depends on negative feedback to keep internal variables fairly constant, with small fluctuations

around set points

Homeostasis: Internal body temperature of approximately 36–38οC

Temperature rises above normal

Temperature falls below normal

Temperature decreases

Temperature increases

Thermostat shuts off warming mechanisms

Blood vessels in skin constrict, minimizing heat loss

Thermostat in brain activates warming mechanisms Skeletal muscles rapidly

contract, causing shivering, which generates heat

Thermostat in brain activates cooling mechanisms

Sweat glands secrete sweat that evaporates, cooling body

Blood vessels in skin dilate and heat escapes

Thermostat shuts off cooling mechanisms

Figure 20.14