"It is not a simple life to be a single cell, although I have no right to say so, having been a single cell so long ago myself that I have no memory at all of that stage of my life."    

— Lewis Thomas.

Janice Lapsansky janice.lapsansky@wwu.edu x7337 Office: BI 305

Office Hours

M 3, W 9, F 1, & by appt.(sign-up on office door)

Hyla regilla,Green tree frog

Learning Objectives 2/11/08

• Introduction to Animal Biology• Review major themes (206) in the context of

animal biology– Continue integration of understanding in 206 &

across 200-level sequence

• Describe how animals are organized (molecular, cellular, tissue, organ, whole organism, & ecosystem levels).– correlate structure and function

• Explain the relationship between size and complexity in animal body organization & their interaction with the environment.

Thematic Questions:• What is an animal?

– How would you know?– How could you be sure?

• What are the key concepts in animal evolution?• What are the “problems” that all animals must solve,

and what adaptations have produced tentative solutions to these challenges in a variety of environments?

Differentiate between “adaptation” and “acclimation”.

What is an Animal? (Review Ch. 32)

• Eukaryotic, multicellular, heterotrophic– Do sponges fall into this category? Why or why not?– Cnidaria?

• Animal cells lack cell walls for support– Do all animals have a skeleton?– What forms might a skeleton take?– How is cell growth & reproduction different in plant and

animal cells?

• Animal cells may be joined by unique types of intercellular junctions– What purpose(s) might these junctions serve?

What is an Animal? (continued)

• Animals have unique tissue types that enable electrical impulse conduction and movement– Name the (4) basic tissue types. Which can conduct

electricity?

• Animals have distinguishing features in their life history– Sexual reproduction (for most)– Dominant diploid stage

– Developmental strategies (“phase change”)

Animal TissuesAnimal Tissues

• Group of similar cellsGroup of similar cells– common embryonic origincommon embryonic origin– common functioncommon function– bound together by intercellular substancebound together by intercellular substance

• 4 basic types4 basic types– What types of cells are found in these tissues?What types of cells are found in these tissues?– What are some of the functions of these cells?What are some of the functions of these cells?

p. 916

Epithelial Tissues

Named according to- cell shape-arrangement

Which would you predict provides the

greatest protection?

Which is/are involved in transport?

Connective Tissues

Describe the role of matrix in c.t.

Describe the function of Mast cells.

Nervous Tissue: A Multipolar NeuronDescribe the relation-ship between structureand function for these cells.

Differentiate between axons & dendrites.

What are the other small dark-staining bodies surrounding this neuron?

Muscle Tissues

Which tissue is involuntarily controlled? …voluntarily controlled?

What intracellular components are responsible for contraction?

Structure of an organ (example)

epithelial

muscular

connective

nervous?

Describe how organs & systems represent a “division of labor”.

1. Like plants, most animals are

aquatic, so they’re not really

that different

Both plants and animals have tissues, so what makes animal anatomy so different?

4. All animals have brains (as well as

brawn).

3. Some animals undergo a drastic change in anatomy known as

metamorphosis2. Animal tissues become highly

specialized, unlike plant meristem

tissues.

Constraints on the size and shape of an animal

p. 921

Bioenergetics

• All living things exchange energy and materials with their environment

• The [finite] energy obtained from the oxidation of energy nutrients is allocated within the animal – support & movement– growth & repair– temperature regulation– reproduction

• Metabolic rate can be measured – heat production– oxygen consumption (or CO2 production)

Surface to Volume Ratio (S/V)• As size increases, volume (and

weight) increases more rapidly• The need for nutrient and waste

exchange is directly related to the volume of the animal body

How does the design of large-bodied animals provide the surface area for adequate exchange with the environment?

Is it safe to assume that small animals are primitive and large animals more specialized?

Fig. 41.9

BMR and body size

p.923

What is BMR, and can you measure it in a snake or fish?

Animal Adaptations & the External Environment

How predictable are these external environments?

• Sea• Freshwater• Land

Can an animal conform to the external conditions?

Things to consider: oxygen availabilitydesiccation threattemperaturefood and water availabilitysalt content

Other variations in form and lifestyle…

• Colonial organization– e.g. corals, bees

Is the parasitic lifestyle associated withparticular body form characteristics?

Symbiotic organizationcommensalismmutualismparasitism

Activity level & posture

Homeostasis of Body Fluids

• Separation of fluid compartments– intracellular fluid (ICF) = within cells– extracellular fluid (ECF) = outside cells

• Composition of fluids change as substances move between compartments– nutrients, oxygen, carbon dioxide, water,

ions and wastes move in both directions

What mechanisms move solutes between compartments?What two forces move water between compartments?

Differential Distribution of Solutes in the ICF and ECF

Regulating the Internal

Environment

The boundary organ concept…

… and homeostasis

Describe the characteristics of “transport epithelia”.

How is this (homeostasis) controlled?

Components of aNegative

Feedback Loop• Receptor

• Control Center

• Effector

Other mechanisms:•Positive Feedback •Feedforward

p. 925

The concept best illustrated in this carton is…

1. Animals employ homeostatic mechanisms to adapt to any environment

2. Animals often alter their environment to improve their chance of survival

3. Animals require specific environmental conditions to survive

4. Animals can survive abrupt climate change

5. Others?