Animal Form and Function Flashcards
Animal form and function are ___ at all levels of organization
correlated
Feedback control maintains the ___ environment in many animals.
Internal
What kinds of physical laws limit the range of animal forms?
Physical laws that govern strength, diffusion, movement, and heat exchange
Discuss properties of water and body shape in water-dwelling organisms (seal, penguin, tuna)
Water is about a thousand times denser than air and far more viscous- therefore any dumb on bodies surface cause more drag.
All have shape that is fusiform- tapered at both ends to swim faster
Physical laws also influence animal body plans with regard to maximum size.
Discuss this.
As body dimensions increase, thicker skeletons are required to maintain adequate support. This limitation affects the internal skeletons and external. Also muscle must be an ever larger fraction of the total body mass.
Whether an organism is single-celled or multicellular, all cells must ___ ___ and get rid of ___.
obtain nutrients; waste
Exchange with the environment for a single-celled organism
single celled have a sufficient membrane surface area in contact with its environment to carry out all necessary exchange
Exchange with the environment for a simple multicellular organism with only two layers
Either the gastrovascular cavity opens to the external environment so both the outer and inner layers of cells are bathed or it is a flat shape
Exchange with the environment for complex multicellular organisms
Specialized surfaces are extensively branched or folded which increase SA
Internal body fluids link exchange surfaces to body cells. What’s this all about?
The spaces between cells are filled with fluid called interstitial fluid. Complex body plans also include a circulatory fluid (blood). Exchange between the interstitial fluid and circulatory fluid enables cells throughout the body to obtain nutrients and get rid of waste.
Cells form a functional animal body through their emergent properties. What does that mean? What is the hierarchy of organization of body plans?
cells arise from successive levels of structural and functional organization;
cells–> tissues->organs->organ stem-> animal
Without going into too many details, what are the organ systems in mammals?
Digestive, circulatory, respiratory, immune and lymphatic, excretory, endocrine, reproductive, nervous, integumentary, skeletal, and muscular
What are the four main types of animal tissues?
Epithelia, connective, muscle, and nerves
What are the general functions of epithelial tissue?
Protection, absorbtion, secretion, diffusion
What are the general functions of connective tissue?
holds tissue and organs together in place
What are the general functions of muscle tissue?
Movement, organ function, circulatory
What are the general functions of nervous tissue?
receipt , processing and transmission of information
How does coordination and control work during long dives by harbor seals?
The seal slows its heart rate, collapses its lungs, and lowers its body temperature while propelling itself forward with its hind flippers
Coordinating activity across an animal’s body requires ___ between different locations in the body.
communication
What are the two major systems for controlling and coordinating responses to stimuli? In general, how do they work?
The endocrine and nervous system.
Endocrine- signaling molecules released into the bloodstream by endocrine cells are carried to all locations of the body.
Nervous- neurons transmit signals along dedicated routes connecting specific locations in the body
An animal is said to be a regulator for a particular environmental variable if
it uses internal mechanisms to control internal change in the face of external fluctuation
An animal is said to be a conformer for a particular environmental variable if
it allows the internal condition to change in accordance with the external changes in the variable
How do some organisms (e.g., the spider crab) conform to more constant environments, such as the relatively stable solute concentration (salinity) of the ocean environment?
Let their internal solute concentration conform to the relatively stable solute of their ocean environment
How can an organism (e.g., a bass) be both a regulator and a conformer? Think about internal versus external temperature, and internal versus external solute concentration
may regulate some internal conditions while allowing others to conform to the environment; the bass conforms to the temp of the water but regulates the solute concentration in its blood and interstitial fluid
What is homeostasis, and what are a couple of examples? What are some examples of homeostasis in humans?
steady state referring to the maintenance of internal balance; study body temp of a river otter and the stable concentration of solutes in a freshwater bass; Humans maintain constant body temp, blood pH, and blood glucose concentration
An animal achieves homeostasis by maintaining a variable, such as body temperature or solute concentration, at or near a particular value, or set point. In general, how does this work?
The animal maintains a variable at or near a set point. A fluctuation in the variable above or below serves as the stimulus detected by a sensor. The control center then generates output that triggers a response to help the variable return to the set point
What is negative feedback?
a control mechanism that reduces the stimulus
What is positive feedback?
a control mechanism that amplifies rather than reduces the stimulus
Does positive feedback really maintain homeostasis?
Not really, more to help drive processes to completion
The set points and normal ranges for homeostasis can change under various circumstances. In fact, regulated changes in the internal environment are essential to normal body function. What are a couple of examples?
Hormone shift during puberty and a woman’s menstrual cycle
What is circadium rhythm?
a set of physiological changes that occur roughly every 24 hours
What is acclimatization? Tell me about the example of an elk or other mammal moving into mountains from sea level
the gradual process by which an animal adjusts temporarily to changes in its external environment; When an elk moves up into the mountains from sea level, the lower oxygen concentration in the high mountain air stimulates the animal to breathe more rapidly and deeply. More CO2 is lost through exhalation, raising blood pH above normal. Over several days, changes in the kidney function to return blood pH to normal
