Form and Function Flashcards
Body shapes are determined by?
habitat
What are the 4 body shapes that are affected by habitat?
- fusiform
- laterally-compressed
- flattened
- snakelike
What is a fusiform body shape?
streamlined shape for active swimmers
What is laterally-compressed body shape?
flattened so can maneuver through corals
What is flattened body shape?
bottom-dwellers
what is snake-like body shape?
burrowing fish
Do endotherms or ectotherms have a higher metabolic rate?
endotherms
What sized animals have a faster endothermic metabolic rate?
smaller
What is torpor?
temporary hibernation; decrease in metabolism (cold)
What is hibernation?
extended state of greatly reduced metabolism (cold)
What is estivation?
a form of torpor occurring when temperatures are high and water is scarce
Do bears hibernate?
no, they go into torpor
Why do smaller animals have a higher metabolism?
bigger bodies have a lower SA:V, so less heat is lost compared to small animals
Why would an animal lower its metabolism on purpose?
allow it to survive through certain conditions such as extreme cold or night where there is less prey
How is animal size limited?
weight of exoskeleton in arthropods and body mass in land animals
What must be true for the body of a land animal?
have enough support to counteract gravity
What is a result of having enough support to counteract gravity?
increased demand for energy
What do animals without circulatory systems rely on?
totally on diffusion
What is a main limiting factor in diffusion?
the distance over which diffusion must take place: as size increases, the SA:V ratio decreases
What does the midsagittal plane do?
divides body into right and left portions
What does the frontal plane do?
divides body into front (dorsal) and back (ventral) portions
What does the transverse plane
divides the body into upper (head) and lower (butt) portions
What does medial mean?
toward the midline
What does lateral mean?
away from the midline
What does proximal mean?
closer to the point of reference
What does distal mean?
further away from the point of reference
What animal group has a diaphragm?
only mammals
What does the diaphragm divide?
divides the ventral cavity into the thoracic and abdominopelvic cavity
What ventral cavity do non-mammal vertebrates have?
coelomic
What two major body cavities do mammals have?
dorsal and ventral
What two major body cavities do non-mammal vertebrates have?
dorsal and coelomic
What makes up the dorsal cavity?
cranial and spinal cavity
What is the purpose of homeostasis?
to maintain the dynamic equilibrium of the body
What things are regulated by hormones?
water balance, temperature, nutrient levels, mineral levels, pH levels
What is the ideal range of something in animals called?
set point
What is homeostasis (?) maintained by?
feedback systems
How do feedback systems work?
sensor->integrator->effector
What does the sensor do?
Monitors the environment (external or internal) and sends information to the integrator
What does the integrator do?
Processes information from the sensors and sends signals or commands to effectors
What does the effector do?
Takes actions to restore the environment to a steady state
What is negative feedback?
changes direction of the stimulus
What is positive feedback?
maintains or strengthens the direction of
the stimulus
What kind of feedback is pregnancy and bloodclotting?
positive; fetus puts pressure on cervix which tells body something happening and signals cause contractions till birth
When does the body regulate temperature? (in response to)
in response to signals from the nervous system
How does the body regulate temperature when body temperature rises?
blood vessels dilate, resulting in heat loss to the environment. Sweat glands secrete fluid. As the fluid evaporates, heat is lost from the body
How does the body regulate temperature when the body temperature falls?
Blood vessels constrict so that heat is conserved. Sweat glands do not secrete fluids. Shivering (involuntary contraction of the muscles) generates heat, which warms the body.
What happens to heat after the body regulates a raised temperature?
heat is lost to the environment
What happens to heat after the body regulated a fallen temperature?
heat is retained
What are the four ways heat can be exchanged?
radiation, evaporation, convection, conduction
What is radiation?
heat transfer from emission of electromagnetic waves
What is evaporation?
transfer of heat as water changes state
What is conduction?
heat transfer by contact with the heating surface
What is convection?
heat transfer by movement of the medium across a surface
