Ch. 42 Animal Form & Function Flashcards
anatomy
the study of an organism’s physical structure
anatomy = build & shape
physiology
the study of how the physical structures in an organism funciton
adaptations
heritable traits that allow individuals to survive and reproduce in a certain environment better than individuals that lack those traits
- result from evolution by natural selection
a genetic change that occurs over generations in response to natural selection in a population
factors that limit adaptations
1) genetics, which can be expensive
2) morphology
3) trade-offs
trade-offs
inescapable compromises between traits
- pervasive (spreads widely) in nature
(ie.) quality vs. quantity of offspring
acclimation
(acclimatization)
a phenotypic change that occurs in an individual in response to a short-term change in environmental conditions
- ability to adapt to change
- example of adaptation
adaptive
description of when a trait/structure helps the individual survive & produce offspring
structure, size, shape or composition correlates closely with its
function
multicellular
bodies contain distinct types of cells that are responsible for different functions
types of tissue
1) connective
2) nervous
3) muscle
4) epithelial
connective tissue
cells loosely arranged in a liquid, jellylike, or solid extracellular matrix
- each type of connective tissue secretes its own distinct type of matrix
types of connective tissue
1) loose connective tissue
2) dense connective tissue
3) supporting connective tissue
4) fluid connective tissue
tissue
a group of similar cells that function as a unit
- cells w/ similar functions
determines the nature of the connective tissue
matrix
loose connective tissue
a type of connective tissue consisting of fibrous proteins in a soft matrix
- FCN: packing material between organs OR padding under the skin
- type of matrix: soft
(ie) adipose tissue
adipose tissue
(fat tissue)
tissue made up of cells that are dominated by fat droplets and a loose matrix of fibers & fluid
- type of loose connective tissue
dense connective tissue
a type of connective tissue, distinguished by having an extracellular matrix dominated by collagen fibers
- found in: tendons & ligaments
- type of extracellular matrix: many tough collagen fibers
supporting connective tissue
a type of connective tissue distinguished by having a firm extracellular matrix
- type of extracellular matrix: firm
- examples: bone & cartilage
function of bone & cartilage
provide structural support for the body & protective enclosures for the brain and other components of the nervous system
fluid connective tissue
a type of connective tissue that consists of cells surrounded by a liquid extracellular matrix
- type of matrix: liquid
- example: blood
blood
a type of fluid connective tissue consisting of red blood cells and leukocytes suspended in a fluid portion (plasma)
- FCN: transports material throughout the body
- its matrix is called plasma
plasma
the non-cellular portion of blood
- type of matrix
nervous tissue
an animal tissue consisting of nerve cells (neurons) and various supporting cells
neuron
(nerve cell)
a cell that is specialized for the transmission of nerve impulses
- made up of dendrites, a cell body & axon
dendrite
a short extension (branch) from a neuron’s cell body that receives/transmits signals from other neurons
axon
a long projection of a neuron that can propagate/promote an action potential
- carries electrical signals from cell body to other cells
muscle tissue
an animal tissue consisting of bundles of long, thin, contractile cells (muscle fibers)
- FCN: movement
- key innovation in the evolution of animals
- appears in no other lineage other than animals
types of muscle
1) skeletal muscle
2) cardiac muscle
3) smooth muscle
skeletal muscle
the muscle tissue attached to the bones of the vertebrate skeleton
- consists of long, unbranched muscle fibers with a characteristic striped (striated) appearance
- voluntary control
- responsible for most body movements
- found in: typical muscles, digestive & urinary tracts
- gives the body shape
- little nuclei
- very strong
- built to move
(ie) encircles & controls the openings of the digestive and urinary tracts
cardiac muscle
the muscle tissue that make up the walls of the heart
- found in: heart
- responsible for pumping blood
- consists of long, branched fibers that are physically & electrically connected
- involuntary control
- many nuclei
- cells point in one direction
smooth muscle
unstriated muscle
- found in: linings of intestine (digestive tract), blood vessels & other organs
- consists of tapered, unbranched cells that can sustain long contractions
- involuntary control
- many nuclei
- cells in all directions
- hold things in place
epithelial tisue
(epithelia)
an animal tissue consisting of sheetlike layers tightly packed cells that line an organ, gland, duct, or body surface
- found in: organ, glands, ducts, or body surface
- FCN: protection & regulate transfer of heat between interior/exterior of structures & transfer water, nutrients, and other substances
- has polarity or sidedness (apical or basolateral)
function of epithelial tissue
1) protection
2) regulate transfer of heat between interior/exterior of structures
3) transfer water, nutrients, and other substances
apical side
(toward the top)
the side of epithelial tissue that faces away from other tissues toward the environment
- has hair for absorption
basolateral side
(toward the base)
the side of epithelial tissue that faces the animals’ interior
- connected to other tissues by basal lamina
basal lamina
a thick, collagen-rich extracellular matrix that underlies most epithelial tissues in animals
- connects epithelial tissue to connective tissue
- layer of fibers found in basolateral side
organs
a group of tissues organized into a functional and structural unit
- tissues w/ similar functions and specialized structures
organ system
groups of tissues and organs that work together to perform a function
rate at which gases, nutrients, and waste products diffuse across membranes depends in part on the amount of ______ available for diffusion
surface area
the rate at which nutrients are used and waste products are produced depends on the _______ of the cell
volume
metabolic rate
the total energy used by all the cells of an individual
- overall rate of energy consumption by an individual
- (aerobic organisms) often measured as the amount of oxygen consumed per hour
basal metabolic rate (BMR)
rate at which an animal consumes oxygen while at rest, with an empty stomach, under normal temperature & moisture conditions
- measured in mL of O2 consumed per gram of body mass per hour
- smaller size, higher BMR
effective ways for structures to have a high surface area/volume ratio
1) flattening
2) folding
3) branching
example of flattening
fish gills have flattened sheet-like structures (lamellae)
example of folding
the mammal small intestine has folds called villi
villi
small, finger-like projections (1) of the lining of the small intestine or (2) of the fetal portion of the placenta adjacent to maternal arteries
- FCN: increase surface area available for absorption of nutrients and gas exchange
example of branching
small blood vessels (capillaries) are highly branched
homeostasis
the maintenance of relatively constant internal environment
- internal chemical & physical states are kept w/in a tolerable range even if animal’s environment changes
types of homeostasis
1) conformation homeostasis
2) regulation homeostasis
conformation homeostasis
homeostasis that occurs by conformation to the external environment
(ie) body T of a fish matches that of the surrounding water
regulation homeostasis
homeostasis that requires a physiological mechanism that adjusts the internal state to keep it w/in limits that can be tolerated, regardless of the external conditions
- most animals
(ie) dog maintains body T of 38˚ C
what happens to body when it’s too hot?
enzyme clumps
proteins denature, cease functioning –> dehydration
what happens to body when it’s too cold?
enzyme breaks up –> slow function
decreased energy production
factors that effect structre & function of enzymes
1) temperature
2) pH
3) other physical and chemical conditions
set point
a normal or target value for a regulated internal variable, such as body heat or blood pH
components homeostatic system is based on
1) a sensor
2) an integrator
3) an effector
why do small mammals lose heat rapidly in cold climates?
their surface area is large relative to their volume
torpor
an energy-conserving physiological state, marked by a decrease in metabolic rate, body temperature, and activity
- lasts for a short period (overnight to a few days or weeks)
- occurs in some small mammals when the ambient (surrounding) temperature drops significantly
hibernation
an energy-conserving physiological state, marked by a decrease in metabolic rate, body temperature, and activity
- lasts for a prolonged period (weeks to months)
- occurs in some animals in response to winter cold and scarcity of food
endotherm
an animal whose primary source of body heat is internally generated
- heat given off by the high rate of chemical reactions is enough to warm the body
- produces adequate heat to warm its own tissues
- extremely high BMR
- more active
(ie) fur in mammals & feathers in birds help them retain heat
ectotherm
an animal that gains most of its body heat from direct environment/external sources
- generate heat as by-product of metabolism
- generate small amount of heat relative to endotherms
- relies on heat gained from environment
- low BMR
- less active
(ie) reptiles bath in sun the get heat
thermoregulation
regulation of body temperature
- important aspect of homeostasis in some animals
effector for homeostasis
metabolic or behavioral responses to neural signals
sensor
a structure that senses some aspect of the external or internal environment
(ie) neural signals from temperature receptors in the skin
sensor –> sense
integrator
a component of the nervous system that evaluates the incoming sensory information and decides if a response is necessary to achieve homeostasis
(ie) hypothalamus interprets neural signals
integrator –> environment
effector
any structure that helps to restore the desired internal condition
effector solves the problem
negative feedback
a self-limiting, corrective response in which a deviation in some variable triggers responses aimed at returning the variable to normal
- represents a means of maintaining homeostasis
ways animals exchange heat with environment
1) conduction
2) convection
3) radiation
4) evaporation
conduction (heat exchange)
direct transfer of heat between two physical bodies that are in contact with one another
(ie) in cold environment, direct skin to skin contact will keep you warmer
convection (heat exchange)
a special case of conduction in which heat is exchanged between a solid and a liquid or gas rather than between two solids
(ie) fire to warm body
radiation (heat exchange)
transfer of heat between two bodies that are not in direct physical contact
(ie) heating water over a flame that is not directly touching the pot
evaporation (heat exchange)
phase exchange that occurs when liquid water becomes a gas
(ie) when a dog sticks out its tongue and breathes hard (pants), the moisture on the tongue turns into water vapor – it evaporates
types of thermoregulation
continuum between:
1) ectotherm & endotherm
3) homeotherm & heterotherm
homeotherm
keep body T constant
heterotherm
can tolerate changes in body T
example of good heat conductor
water
example of good insulator
air (bad heat conductor)
countercurrent exchanger
any anatomical arrangement that allows the maximum transfer of heat or a soluble substance from one fluid to another
- the 2 fluids must be flowing in opposite direction & have a heat or concentration gradient between them
(ie) gray whale tongue conserves heat
(ie) heat flows freely from warm arteries to cool veins, allowing heat that would otherwise be lost to the surroundings to be returned to the body
