124 terms

Chapter 40

Campbell Biology
anatomy is
study of the biological form of organism
Phsyiology is
biological functions an organism performs
Form and function are correlated at all levels or organization how?
-size and shape affects environment, interaction
-body plans have evolved
-physical laws constrain body plans
-increase in size causes proportionately large skeleton for support
Organisms exchange with enviornment
-multicellular organisms need nutrition, oxygen, excrete waste
-organisms have various systems where purposes are separated
-inside and outside surface conduct exchange
-every single cell has fluid cwhich facilitates movement of material in and out of cell
Rate of exchange is proportionate to
a cell's surface area
Rate of exchange material is proportionate to
volume of cell
What is intersitital fluid
Facilitates movement of material in and out of cells
Claude Bernanrd coined
-body tries to keep things within a normal range NOT SET POINT
Cells are organized into
cells -> tissues -> organs ->organ system (work together to do a job)
Animal tissues types (4)
1) epithelial
2) connective
3) muscle
4) nerve
Two major ways of coordination by body
1) signal hormone - slow but long lastic
2) signalling neurons - quick
both help to coordinate function in body
Nerve cells
can connect to other cells
-neurostransmitters are molecles that release into cell receptors on surface
What is feedback control?
-way animals manage internal environment viea regulation or conforming to external environment
for example, thermoregulation. Either 1) animal changes internal control to moderate temperature or 2) allow the internal change to temp due to the external change
What happens if you go out of normal range?
above or below normal range, and you can die
Negative feedback
Your body will create products to stop something or prevent something from happening. sweating to prevent overheating.
positive feedback
feedback strengthens until something stops
Animal form and function are related at all levels of organization. How?
-interacting with environment - size and shape, parts of form, affect the way animals interact
-Genome determines many different body plans and how they evolve
-Physical laws constraint - constrain stength, diffusion, movement, head exchange
-as animals increase in size, their skeletons must be proportionately larger to support their mass
-evolutionary convergence - reflects different species adaptations to similar environmental challenges
what needs to be exchanged across membranes of animal cells
nutrients, waste products, gases
what is the rate exchange proportional to?
cell's surface area
what is amount of exchange material proportional to?
How do small, simple organisms exchange material with their enviornment?
-small animals have enough surface area of plasma membrane to service entire cytoplasm
-ameobas have body plans that enable direct exchange b/w all of their cells and the enfironment
How do multicellular organisms with a saclike body plan exchange with their environment?
Sac like body plan have cell walls that are only two cells thick. It helps with the exchange of material between water and cells
an increase in the number of cells in multicellular orgnaisms
-decreases ratio of outer surface area:volume
-so animals have specialized sufaces that are extended, branced or folded
-all cells re surrounded by intersititial fluid for exchange
What is the space between cells called?
Intersititial fluid, also called ECM
-allows for moevement of material into and out of cells
-also complex animals have circulatory fluid, which is like blood - a way to exchange nutrients and dumb waste
Complex body plans help
animals living in environments that are variable but they want to maintain a relatively stable intenral environment (i.e. land animals)
How are body plans organized?
-specialized cells are grouped into tissues
-tissues have different functions, and congregated together they make up organs
-organs make organ systems, some organs are part of more than one system
Digestive system
Main components: moth, pharynx, esophagus, stomach, intestines, liver, pancreas, anus

Function: food processing
Circulatory system
components: blood, heart, blood vessels

function - internal distribution of materials
components - lungs, trachea, other breathing tubes

gas exchange
immune and lymphatic
bone marrow, lumph nodes, spleen, white blood cells

body defense
kidneys, ureters, urinary bladder, urethra

disposal of metabolic wastes, regulation of osmotic balance of blood
pituitary, thyroid, pancreas, adrenal, other hormone secreting glands

coordination of body activities
ovariers, testes, associated organs

brain, spinal cord, nerves, sensory organs

boordination of body activities, detection of stimuli and formulation of responses
skin and its derivatives
protection against mechanical injury, infection, dehydration; thermoregulation

body support, preotection of internal organs, movement
skeletal muscles

locomotion and other movement
what are four different tissue types?
1) epithelial - lining
2) connective
3) Muscle
4) nerve
Epithelial tissues
cover outside of body and line organ body cavities within body
Kidneys and many glands often have which type of epithelial tissue?
simple cuboidal
When secretion or active absoprtion is important, like intestines, secreting digestive juices, what type of cells are used?
simple columnar epithelium
what generally lines blood vessels, air sacs of lungs, and other places when maximum nutrient and gas diffusion is critical?
simple squamous epithelium
What generally is needed when multilayered cells need to generate rapidly? This cell is common on surfaces subject to abrasian like outser skin and linings to mouth, anus, and vagina
stratified squamous epithelium
What lines ciliated cells that form mucous membranes
Pseudostratified columnar
What type of tissue holds organs and other tissues in place? It is mostly sparse number of cells which secrete lots of ECM
connective tissue
What are some things that you will see in connective tissue?
web of fibers
-fibrobrasts - secrete fiber proteins
-macrophages - engulf foreign particles
What are the five types of connective tissue?
1) loose - widespread, binds epithelia to underlying tissues, holds organs in place
2) fibrous - dense with collagen, found in tendons and ligaments
3) bone - calcified connective tissue
4) adipose - fat, pads and insulate
5) cartilege - collagenous fibers
What are the three types of muscle tissues?
1) skeletal - striated bundles of long muscle tissue, controlled by nerve cells, attached to bones and tendons. have many nuclei, and controls VOLUNTARY MOVEMENT
2) smooth - lacks striations, in walls of tracts, spindle shaped, involuntary movement
3) cardiac - branches, has striations, found in heart only
How does the body coordinate and control?
1) signal by hormones
2) signal by neurons
Signalling by hormones
the stimulus is felt by the endocrine cell
cell secretes hormone
hormone travels everhwhere, then finds its way to blood vessel
which travels to certain cells that have the receptor and they do wht the hormones says
signalling by neurons
stimulas goes into cell body of neurons, travels down axon to a specific location
-information conveyed depends on a signal's pathway
-is very fast, can be received by neurons, muscle cells, endocrine cells, exocrine cells
-often the signal reaches its target by the release of neutransmitters into the small space between the nerve cell and its target
-target has receptors for neurtransmitters
Neurons are
basic units of nervous system, has dendrites, cell body, axon
help nourish, insulate, replenish and sometimes regulate neurons
How do animals manage their internal environment?
-by regulating
-by conforming to the external environment
-animals may regulate some environmental variables while conforming to others
What is a regulator
A regulator uses internal control mechanisms to moderate internal change in the face of external, environmental fluctiation
What is a conformer
allows its internal condition to vary with certain external changes
What is homeostasis
-internal balance regardless of external environment
-this is a normal range
-in humans, body, pH, glucose concentration are each maintained within a normal range
What are some mechanisms of homeostasis
-stimulus - fluctuations above and beyond a certain range
-sensor - detects stimulus, triggers response
-response returns the variable to within acceptable range
What is acclimatization
Adjustment to changes in external environment
What is negative feedback?
-buildup of end product shuts the system off
-helps return a variable to a normal range
What is positive feeback?
-amplifies a stimulus and does NOT usually contribute to homeostasis in animals
What is the circadian rhythm?
-governs physiological changes that occur roughly every 24 hours
What ir thermoregulation?
process by which animals keep internal temperature within a tolerable range
-biochemical and physiological processes are sensitive to body temperature
What are endotherms?
-Animals that generate heat by metabolism (birds and mammals)
-more energetically expensive
-active at a greater range of external temperatures
What are ectotherms?
Animals gain heat from external sources, like the sun (reptiles, fishes, etc).
-can tolerate greater variation in internal temperature
-eat less than ectoterms and can tolerature large internal variations in temp
Which type of thermoregulator can tolerate large internal temperature variations?
Which type of thermoregulator can tolerate a larger range of external temperatures?
What is a poikilotherm?
-body temp varies with its environment
-not all poikilotherms (temp varies with environment) are ectoterms (get heat source from outside)
What is a homeotherm>?
body temperature is relatively constant
-not all homeotherms are endotherms. some are ectothermic but live in one type of environment
What are the four ways an organism exchanges heat with its surroundings?
1) radiation - emits EM waves
2) evaporation - removal of heat from surface by evaporating liquid
3) convection - wind blowing or water flowing through, removes hot on surface
4) conduction - direct transfer of heat between two organisms
Mammals often use what system for thermoregulation?
-integumentary system: skin, hair, nails
What are five adaptations that help animals thermoregulate?
1) insulation - skin, feathers, fur and blubber reduce heat flow between animal and environment
2) circulatory adaptations - regulation of blood near body surface, entrapment of heat in body core
3) cooling by evaporative heat loss
4) behavioral responses - such as bathing, burrowing, hiding in the shade
5) adjusting metabolic heat production - shiver to increase heat (thermogenesis)
-major thermoregulatory adaptation in mamals and birds
-espeecially important in marine mammals such as whales and walruses because water is colder than body core near freezing polar seas
Circulatory adaptations
-regulation of blood flor near the surface of the body or traping heat within body core
-many endotherms can alter amount of blood fow between the body core and skin
-vasolidation - blood flow to skin increases, loses heat
-vasoconstriction - blood flow to skin decreases, lowering heat loss
-countercurrent exchange -transfer heat between fluids flowing in opposite directions to allow cooling of organs
What is vasolidation?
blood flow in the skin increases, facilitating heat loss
What is vasoconstriction
blood flow to the skin decreases, lowing heat loss
What is countercurrent exchange
-arrangement of blood vessels in may marine mammals and birds allow countercurent exchange
-it is transfering heat between fluids going in opposite directions to cool an organ (like tetis)
-many endothermic insects have countercurrent heat exchangers near thorax to keep high temps - flight muscles warm!
Evaporative Heat Loss
-lose heat through evaporationof water from their skin (sweating)
-panting increases the cooling effect in birds and many mammals
What are some behavioral responses as adaptations for thermoregulation?
-postures that minimize or maximize absorption of solar heat
-hiding during the day, staying in a/c
What are some adjustments to metabolic heat production?
-endotherms counteract heat loss by varying heat production
-this is called thermogenesis
-shivering increases heat
-some ectotherms can also shiver to increase body temp
What do mammals use for thermogenesis?
brown fat, specialized for rapid heat production
What is nonshivering thermogenesis?
take places when hormones cause mitchondia to increase metabolic activity
How do animals acclimate?
-birds and mammals can very their insulation to seasonal temp changes
-antifreeze is produced to prevent ice formation in cells
-hypothalamus in birds and mammals triggers heat loss or heat generating mechanisms (fever, shivering)
-fever is the results of a change to the set poit for a biological thermostat - this is mostly done by the hypothalamus
overall flow and transformation of energy in an animal
-determiens how much food an animal needs, and it relates to an animals size, activity and environment
What are energy requirements related to?
-animals size
-animal's activity
Energy allocation and use
-animals harvest chemical energy from food
-molecules are used to make ATP
-ATP powers cellular work
-remaining food can be used in biosynthesis
What is biosynthesis
-body growth and repeait
-synthesis of storage material such as fat
-production of gametes
What is metabolic rate?
-amount of energy and animal uses in a unit of time
-is determine by animal's heat loss
-animals amount of oxygen consumed
-carbon dioxide produced
What is the basal metabolic rate
-rate of an endotherm at rest in a comfortable temperature
What is standard metabolic rate?
-metabolic rate of an ECTOTHERM at rest at a specific temperature
What do both basal and standard metabolic rates assume?
-nongrowing, fasting and non stressed animal
Which type of thermoregulator has lower metabolic rates when both organisms have comparable size?
What are some influences on metabolic rate?
-size and activity
How does size affect metabolic rate?
-metabolic rate is porportional to body mass to the power of 3/4 (rate =m^(3/4))
-Smaller animals have higher metabolic rates per gram than larger animals!!!
What do the higher rate of smaller animals leads to
-higher oxygen delivery rate
-higher breathing rate
-higher heart rate
-greate blood volume
How does activity affect metabolic rate?
-max rate an animal can sustain is inversely related to the durating of the activity
What is torpor
physiological state in which activity is low and metabolism decreases
-enables animals to save enrgy while avoiding difficulat and dnagerous conditions
What is hibernation?
long term winter torpor
-adaptation to winter and cold and food scarcity
What is summer torpor?
-enables animals to survive long periods of high temepratures and scarce water
what is daily torpor?
-small mammals and birds have low activity and low metabolism in tune with their feeding patterns
Which of the following would increase the rate of heat exchange between an animal and its environment?
-feathers or fur
-wind blowing across the body surface
-countercurrent heat exchanger
-blubber or fat layer
wind blowing across the body surface
Compared with a smaller cell, a larger cell of the same shape has
less surface area per unit of volume.
An animal's inputs of energy and materials would exceed its outputs
-f it is growing and increasing its mass.
-ever; homeostasis makes these energy and material budgets always balance.
-f the animal is an endotherm, which must always take in more energy because of its high metabolic rate.
-f it is actively foraging for food.
-f it is hibernating.
if it is growing and increasing its mass.
Which of the following animals uses the largest percentage of its energy budget for homeostatic regulation?
- desert insect
- hydra
- snake in a temperate forest
- marine jelly (an invertebrate)
- desert bird
desert bird
Which of the following systems is correctly paired with one of its parts?
endocrine system ... thyroid gland
Which of the following are types of cells found in epithelial tissues?
-erythrocytes and platelets
-chondrocytes and osteocytes
-fibroblasts and osteoblasts
-squamous, cuboidal, and columnar cells
squamous, cuboidal, and columnar cells
Where in the body would you be most likely to find secretory cells shaped like dice?
thyroid and salivary glands
Microscopic analysis of an unknown tissue sample reveals the presence of chondrocytes, indicating that the sample was probably taken from _____ tissue.
Osteocytes are
bone tissues
Cells that secrete the proteins that make cartilage strong yet flexible are called _____.
Ligaments connect _____ to _____.
bone to bone
Tendons connect __ to ____
bone to muscle
When we talk of feedback systems, the word "stimulus" means _____.
a deviation off the accepted range
The role of an effector in a feedback loop is to _____.
to influence the stimulus
Which statement is true regarding thermoregulation?
-Endotherms must always maintain a fairly constant body temperature to survive.
-An ectotherm such as a lizard does not maintain a fairly constant body temperature.
-Ectotherms generally do not conserve body heat as effectively as do polar bears.
-In furry animals, raised hairs keep the animal cooler than lowered hairs.
-A dilated blood vessel conserves more heat than a constricted one.
Ectotherms generally do not conserve body heat as effectively as do polar bears.
On a cold day, blood vessels in the skin _____.
constrict, reducing heat loss from blood at the surface
Dilation of blood vessels on the skin cause
diameter of blood vessels to increase, in this case increasing blood flow to the skin and heat loss at the same time.
When your body temperature is too _____, _____ helps to correct the situation because it _____.
high ... peripheral vasodilation ... redirects heat from the body core to the outside
Which description is a behavior that helps warm the body?
-Sweat oozes from the hide of a thirsty antelope in the drought-stricken Serengeti plains.
-A man gets "goosebumps" after walking outside in the winter without a jacket.
-An elephant rolls in the mud and sprays water over its back.
-A woman puts on a wide-brimmed hat while laboring in the sunshine.
-A falcon migrates from San Francisco to Brazil for the winter.
A falcon migrates from San Francisco to Brazil for the winter.
In the late fall, bats hibernate in clusters with many bats pressed together and holding on to one another. Which of the following supposed advantages of huddling behavior is, in reality, not true?
-Any heat generated by any bat is shared by other bats.
-Less surface area is exposed to the environment.
-In this configuration, less heat is needed for each bat and, therefore, each bat requires less food.
-Huddling behavior helps bats stay warm while they feed.
-Huddling behavior decreases the amount of food needed for bats to stay warm.
Huddling behavior helps bats stay warm while they feed.
The amount of energy expended while an endothermic organism is resting, unstressed, and not actively digesting or growing is called its _____.
basal metabolic rate
homeostatic control
-sensors - detects change that is higher or lower than range, sends information to integrator
-integrator - compares this to accepted range, and then sends instructions to effector
-effector then does the action
this is circular
Which of the following actions is not a function of the epithelium?
-Regulates the excretion of waste.
-Controls the exchange of nutrients between the internal and external environments.
-Allows the internal environment to alter its conditions to match those of the external environment.
-Creates an internal environment that is different from the external environment.
-Allows the internal environment to alter its conditions to match those of the external environment.
-this is not true because The epithelium allows the internal environment to remain constant even if the external environment changes.
A countercurrent heat exchanger enables an animal to _____.
-absorb heat from the environment
-reduce the loss of body heat to the environment
-increase heat loss by evaporation
-slow metabolism when food is not available
-produce more heat when needed
-reduce the loss of body heat to the environment