This document provides an introduction to animal form and function. It discusses how an animal's form reflects biological themes like structure and function. The principle of complementarity is explained, relating an organism's hierarchical structure to its emergent properties. Body plans are shaped by evolution to suit an animal's external environment. Homeostasis and feedback mechanisms regulate an animal's internal environment. Animals harvest chemical energy as heterotrophs from food, while plants are autotrophs harvesting energy from sunlight and carbon dioxide. Metabolic rate and bioenergetic strategies vary with body size and thermal regulation approach.

1. Introduction
to Animal
Form &
Function
Prepared by: Ms. IRISH M. SEQUIHOD

2. OBJECTIVES
• Reflect animal form and function to Biology’s major theme.
• Explain the principle of Complementarity.
• Discuss the rationale of body plans in relation to external
environment.
• Discuss the concept of Homeostasis.
• Describe the different forms of chemical energy harvest of life
forms.

3. Animal form reflects Biology
theme
•Structure and function
•Emergent properties
•Evolution (natural
selection)
•Regulation

4. Function Correlates with
Functions
•Complementarity Principle
•Life characterized by hierarchical
levels of organization, each with
emergent properties.
•Hierarchical Structure
•Organized but complex

5. Function Correlates with
Functions

6. Structural Organization

7. The Organ Systems of Animal
are Interdependent

8. The Organ Systems of Animal
are Interdependent

9. Body plans and the External
Environment
• An animal’s size and shape, features that
biologists often call body plans or designs,
are fundamental aspects of form and
function that significantly affect the way
an animal interacts with its environment.
• The body plan or design of an animal
results from a pattern of development
programmed by the genome, itself the
product of millions of years of evolution
due to natural selection.

10. Physicallawsconstrain
animalform

11. Body size and shape
affectinteractions with
the environment.

12. Body size and shape affect interactionswith the
environment.

13. Regulating the Internal
Environment
• Mechanisms of Homeostasis moderate changes
in the internal environment.
• Homeostasis means “steady state”
• Homeostasis – depends on feedback circuits
negative feedback – a change in a variable
being monitored triggers the control mechanism
to counteract further change in same direction.
positive feedback – a change in some
variable triggers mechanisms that amplify rather
than to reverse the change.

14. Negative
Feedback

15. Positive Feedback

16. Introduction to the
Bioenergetics
• According to source of energy
• According to carbon source
• Animals are heterotrophs that harvest
chemical energy from the food they eat.
• Plants are autotrophs that they harvest
chemical energy from carbon
dioxide, water, and sunlight.

17. Introduction to the
Bioenergetics
• After the energetic needs of staying alive
are met, any remaining food molecules
can be used in biosynthesis, including
body growth and repair, synthesis of
storage material such as fat, and
production of reproductive structures,
including gametes.

18. Introduction to the
Bioenergetics
• Metabolic rate provides clues an animal’s
bioenergetic “strategy”.
• The flow of energy through an animal - the
animal’s bioenergetics – ultimately sets
the limits to the animal’s
behaviour, growth, and reproduction and
determines how much food it needs.
• Metabolic rate – the amount of energy an
animal uses in a unit of time.

19. Two Basic Bioenergetic “strategies”
• Endothermic - bodies are warmed by heat
generated by metabolism, and their body
temperature must be maintained at a
certain level to sustain life.

20. Two Basic Bioenergetic “strategies”
• Ectothermic - do not produce enough metabolic
heat to have much effect on body temperature.

21. Metabolic Rate vs. Body Size &
Condition
•Metabolic rate per gram is inversely
related to body size among similar
animals.
•Animals adjust their metabolic rates
as conditions change.
•Basic Metabolic Rate (BMR) vs.
Standard Metabolic Rate (SMR)

22. Metabolic Rate vs. Body Size &
Condition
•In general, an animal’s
maximum possible
metabolic rate is inversely
related to the duration of
activity.

23. Metabolic Rate vs. Body Size &
Condition
• Both an alligator (ectotherm) and a human
(endotherm) are capable of very intense
exercise in short spurts of a minute or less.

24. Metabolic
Rate vs. Body
Size &
Condition

25. Energy budgets reveal how animals
use energy and materials