Chapter 3 Animal Form and Function & Homeostasis

Form (Anatomical) Adaptations

Structural adaptations that help maintain an animal internal environment; example: insulating fur and body structures reduce heat loss in cold environments

Function(Physiological adaptations)

Physiological mechanisms that generate or conserve heat and other body functions; example: shivering produces metabolic heat to maintain body temperature in cold environments

Behavior adaptations

Actions and behaviors that help animals maintain homeostasis; example: penguins packing together reduces exposure to cold and decreases heat loss through group thermoregulation

Anatomy

Physical structure or form an organism; ex: an elephant ears are loaded with blood vessels

Physiology

Function of physical structure in an organism. EX: Elephant shunt blood to the surface of their ears where body heat can be lost.

Adaptation

Heritable trait that provides better chance of survival and/or reproduction in certain environment; Adaptive structure correlates with function. EX: beak size/shape correlate with diet.

Acclimatization

Phenotypic change of individual in response to environment. Short term and reversible. Ex: Athlete training at high elevation would acclimatize and produce more RBCs

Tissue

Group of similar cells that work together to perform the same function

Epithelial tissue

Occurs as sheets of closely packed cells, covering the outside of the body and lines organs and cavities

Connective tissue

consists of cells scattered through an extracellular matrix, often forming a web of fibers

Muscle tissue

consists of filaments containing actin and myosin, which enable the muscles to contract

Nervous tissue

functions in the receiving, processing, and transmission of information

Organ

group of tissues that function together. EX: Small intestine made of muscle, nervous, connective, & epithelial tissues.

Organ system

groups of tissues and organs that function together

Digestive system

Mouth, pharanx, Esophagus, stomach, intestine, liver, pancreas,anus; Responsible for food proccessing(ingestion,digestion,absorbtion, elimination)

Circulatory

Heart, blood vessels, blood; Main function→ internal distribution of materials.

Respiratory

Lungs, Trachea, and other breathing tubes; Main functions→ Gas exchange(uptake of oxygen; disposal of carbon dioxide.)

Immune and lymphatic

Bone marrow, lymph nodes, thymus, spleen, lymph vessels. Main functions→Body defense(fighting infections and virally induced cancers); fluid distribution(lymphatic system only)

Excretory

Kidney, ureters, urinary bladder, urethra. Main functions→Disposal of metabolic wastes; regulations of osmotic balance of blood

Endocrine

Pituitary, thyroid, pancreas, adrenal, and other hormone-secreting glands. Main functions→Coordination of body activities( such as digestion and metabolism)

Reproductive

Ovaries or testes and associated organs. Main function →Gamete production; promotion of fertilization; support of developing embryo.

Nervous

Brain, spinal cord, nerves, sensory organs. Main functions→Coordination of body activities; detection of stimuli and formulation of response to them.

Integumentary

Skin and its derivatives( such as hair, claws, sweat glands). Main function→Protection against mechanical injury, infection, dehydration; thermoregulation.

Skeletal

Skeleton( bones, tendons, ligaments, cartilage). Main function→Body support, protection of internal organs, movement.

Muscular

Skeletal muscles. Main function → locomotion and other movement.

Body size constraints

Gravity limits how large an animal can be and still move efficiently; large animals need more food, produce more waste, take longer to mature, reproduce slower, and often live longer; smaller animals lose heat and water more rapidly

Homeostasis

A “ steady state” or internal balance

Regulator

Can maintain internal conditions despite external fluctuations. EX: river otter.

Conformer

Allows internal condition to change with external fluctuations. Ex: Largemouth Bass

Optimal enzyme function

They are proteins that catalyze chemical reactions within cells; temperature, pH, and other factors impact the structure and function of enzymes.

Physiological function

Molecules, cells, tissues, organs, and organ systems function at an optimal level when homeostasis occurs; homeostasis sets the range of conditions under which bodies are functional

Thermoregulation

The maintenance of internal body temperature within a normal, functional range despite changes in external environmental temperature

Endothermic animals

Animals that generate heat by metabolism; includes birds and mammals; can maintain stable body temperature regardless of external environment.

Ectothermic animals

Animals that gain heat from external sources; includes invertebrates, fishes, amphibians, and non-avian reptiles; body temperature varies with external environment.

Vasodilation

Widening of blood vessels to increase blood flow to the skin surface and promote heat loss to the environment

Vasoconstriction

Narrowing of blood vessels to decrease blood flow to the skin surface and reduce heat loss to the environment.

Concurrent exchange

Transfer of heat between fluids flowing in opposite directions; the most efficient way for organisms to reduce heat loss (e.g., in flipper arteries and veins of dolphins).

Radiation

Transfer of heat energy in the form of electromagnetic waves from an object to its surroundings.

Sensor

Structure that senses external or internal environment

Integrator

Evaluates sensory info, compares to set point, and develops response.

Effector

Structure that restores internal condition being monitored.

Convection

Transfer of heat through the movement of air or water currents

Conduction

Direct transfer of heat between objects in contact

Evaporation

Transfer of heat through the conversion of liquid water to water vapor

Heat gradient

A difference in temperature between two regions; heat moves from higher to lower temperature