ch. 40 Flashcards
anatomy
form
physiology
biological functions
what do physical laws govern
strength, diffusion, movement, heat exchange
what do properties of water limit
possible shapes for fast swimming animals
as animals increase in size, what is required?
thicker skeletons for support
how are nutrients, waste products, and gases exchanged
across the cell membranes
rate of exchange is proportional to what
cell’s surface area
amount of exchange material is proportional to what
cell’s volume
what does a single-celled organism have sufficient surface area for?
all necessary exchange
what do multicellular organisms with a sac-like body plan have?
body walls tat are only 2 cells thick, facilitating diffusion of materials
what are most cells in contact with in tapeworms?
the environment
space between cells
filled with interstitial fluid
interstitial fluid
links exchange surfaces to body cells
what does a complex body plan do
helps animal living in variable environment to maintain stable internal environment
inter
between
hierarchy of organization of body plants
atom, molecule, macromolecule, organelle, cell, tissue, organ, organ system, organism
4 types of animal tissues
- epithelial
- connective
- muscular
- nervous
where is epithelial tissue found
- covers outside of body
- lines organs and body cavities
cells in epithelial tissue
contains cells that are closely joined
types of epithelial tissue
- stratified squamous
- pseudostratified columnar
- simple squamous
- simple columnar
- cuboidal
connective tissue function
binds and supports other tissues
connective tissue cells
- sparsely packed cells scattered in extracellular matrix
- matrix consists of liquid, jellylike, solid foundation
3 types of connective tissue fibers
- collagenous fibers
- reticular fibers
- elastic fibers
collagenous fibers
provide strength flexibility
reticular fibers
join connective tissue to adjacent tissues
elastic fibers
stretch and snap back to original length
2 types of connective tissue cells
- fibroblasts
- macrophages
fibroblasts
secrete protein of extracellular fibers
macrophages
involved in immune system
fibro
fiber
blast
lay down
macro
large
phage
eat
6 major types of connective tissue
- loose connective tissue
- fibrous connective tissue
- bone
- adipose tissue
- blood
- cartilage
loose connective tissue
binds epithelia to underlying tissues and holds organs in place
fibrous connective tissue
- found in tendons (bone to muscle)
- found in ligaments (bones at joints)
bone
mineralized and forms the skeleton
adipose tissue
stores fat for insulation and fuel
blood
composed of blood cells and cell fragments in blood plasma
cartilage
strong and flexible support material
muscle tissue function
body movement
muscle cell composition
- consist of filaments of proteins actin and myosin enable muscles to contract
- myoblast and myocyte
3 types of muscle
skeletal, smooth, cardiac
skeletal muscle
- striated
- voluntary
- multinucleated
cardiac muscle
- involuntary
- branched
- intercalated discs
smooth muscle
- involuntary
nervous tissue function
receipt, processing, transmission of information
nervous tissue cells
- neurons (nerve cells) - transmit nerve impulses
- glial cells (glia) - support cells
what does coordination and control depend on
nervous and endocrine system
endocrine system
releasees signaling molecules called hormones into bloodstream
hormones
- affect 1+ regions throughout body
- relatively slow acting with long lasting effects
what does relayed information depend on
signal’s pathway, not type of signal
regulators
use internal control mechanisms to maintain homeostasis
conformers
allows internal condition to vary within certain external changes
are animals regulators or conformers
both
homeostasis
steady state or internal balance regardless of external environment
homeostasis in humans
- body temperatures
- blood pH
- glucose levels
for a given variable, fluctuations above/below a set point serves as what?
stimulus
what is a stimulus detected by
a sensor
what does a control center do
generates output that triggers a response, which returns variable to set point
negative feedback
helps return variable to normal range
- most homeostasis in animals
positive feedback
amplifies stimulus
- doesn’t usually contribute to homeostasis
how do set points and normal ranges change
- age
- cyclic variation
circadian rhythm
govern physiological changes that occur every 24 hours
acclimatization
a temporary change during an animal’s lifetime
thermoregulation
process by which animals maintain internal temperature within a normal range
endothermic animals
generate heat by metabolism
- birds, mammals, endotherms
ectothermic animals
gain heat from external sources
- invertebrates, fishes, amphibians, reptiles
is endothermy or ectothermy more energetically expensive
endothermy
do ectotherms or endotherms tolerate greater variation in internal temperature
ectotherms
body temperature of poikilotherm
varies with environment
poikio
variable
body temperature of homeotherm
relatively constant
relationship between heat source and body temperature
not fixed (not all poikilotherms are ectotherms)
4 physical processes by which organisms exchange heat
- radiation
- evaporation
- convection
- conduction
what system is often involved in heat regulation in mammals?
integumentary system - skin, hair, and nails
5 adaptations help animals thermoregulate
- insulation
- circulatory adaptations
- cooling by evaporative heat loss
- behavioral responses
- adjusting metabolic heat production
insulation
- mammals (whale, walrus) and birds
- skin, feathers, fur, blubber reduced heat flow between animal and its environment
circulatory adaptations
- regulation of blood flow near body surface
- end/exotherms can alter amount of blood flowing between body core and skin
- vasodilation
- vasoconstriction
vasodilation
blood flow in skin increases, facilitating heat loss
vasoconstriction
blood flow in skin decreases, lowering heat loss
countercurrent exchange
exchangers transfer heat between fluids flowing in opposite directions and thereby reduce heat loss
- from arrangement of blood vessels in marine mammals and birds
what organisms use countercurrent heat exchanges?
some sharks, fish, insect, marine mammals, birds
endothermic insects and countercurrent heat exchangers
help maintain high temperature in thorax
evaporative heat loss
- evaporation of water through skin
- sweating/bathing moistens skin
- panting - birds and mammals
behavioral responses
- ecto, sometimes endoderms
- seek warm places when cold
- seek cooler areas when hot
adjusting metabolic heat production
- thermogenesis
thermogenesis
adjustment of metabolic heat production to maintain body temperature
- increased by moving and shivering
non shivering thermogenesis
takes place when hormones cause mitochondria to increase metabolic activity
brown fat
tissue in mammals specialized for rapid heat production
where is brown fat found
infants of many mammals and adult mammals that hibernate
what does amount of brown fat in human adults depend on
varies depending on temperature of surrounding environment
what other animals can raise body temperature through shivering
birds and some nonavian reptiles
how can birds and mammals vary their insulation
to acclimatize to seasonal temperature changes
what happens to lipid composition of cells with temperature change?
may change
antifreeze compounds
when temperatures are subzero, some ectotherms produce these compounds to prevent ice formation in cells
what is thermoregulation controlled by
hypothalamus
what does the hypothalamus trigger
heat loss or heat-generating mechanisms
fever
response to some infections
- reflects an increase in normal range for biological thermostat
bioenergetics
overall flow and transformation of energy in an animal
what does bioenergetics determine
nutritional need, size, activity, environment
how can organisms be classified
by how they obtain chemical energy
autotrophs
harness light energy to build energy-rich molecules
- plants
heterotrophs
harvest chemical energy from food
- animals
what are energy-containing molecules from food used for
making ATP, which powers cellular work
what are food molecules used for after staying alive needs are met?
biosynthesis
biosynthesis
- body growth and repair
- synthesis of storage material (fat)
- production of gametes
what does food become
ATP to glycogen to fat
metabolic rate
sum of all energy an animal uses in a unit of time
what can a metabolic rate be determined by
- animal’s heat loss
- amount of O2 consumed or CO2 produced
- measuring energy content of food consumed and energy lost in waste products
anabolism + catabolism =
metabolism
basal metabolic rate (BMR)
metabolic rate of endotherm at rest at comfortable temperature
standard metabolic rate (SMR)
metabolic rate of ectotherm at rest at specific temperature
what do both types of metabolic rates assume
non growing, fasting, non stressed animal
do ectotherms or endotherms have lower metabolic rate
ectotherms
factors influencing metabolic rates
age, sex, size, activity, temperature, nutrition
what is metabolic rate proportional to
body mass to the power of three-quarters
do smaller or larger animals have a higher metabolic rate per gram
smaller animals
what does a higher metabolic rate of smaller animals lead to
higher oxygen delivery rate, breathing rate, heart rate, greater blood volume
- compared to larger animals
torpor
physiological state of decreased activity and metabolism
- enables animals to save energy while avoiding difficult/dangerous conditions
hibernation
long-term torpor that is an adaptation to winter cold and food scarcity
estivation
summer toropor
- enables animals to survive long periods of high temperatures and scarce water
daily torpor
- exhibited by many small mammals and birds
- adapted to feeding patterns
simple squamous
lung sacs
pseudostratified columnar
respiratory tract
stratified squamous
skin, esophagus
simple columnar
intestine
simple cuboidal
kidney
