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Darwin was inspired by these to think about evolution
Books, fossils, adaptations of organisms to the environment, and unique organisms on the Galapagos Islands
These create genetic variation
mutation and sexual recombination
Breeding of plants and animals by humans
Microorganisms can adapt to changes in the environment by means of mutation alone because
They multiply so rapidly
The smallest unit that can evolve
Differential reproduction is another way of saying
What changes in a gene pool results in adaption to an envrionment
The ultimate source of genetic variation is...
An organisms fitness is measured by its..
contribution to the gene pool of the next generation
Animals that possess homologous structures probably
evolved from the same ancestor
Two animals are considered different species if they...
What is the first step in allopatric speciation?
the science of describing, naming, and classifying organisms
Why are species most commonly identified by their appearance?
This is the most convenient way of identifying species
A new species can arise in a single generation if
a change in chromosome number creates a reproductive barrier
evolution from a common ancestor of many species adapted to diverse environments
Evolution occurs in spurts; species evolve relatively rapidly, then remain unchanged for long periods, according to what?
Punctuated equilibrium model
the appearance of a new species in the same area as the parent population
individuals of different species living in te same area may be prevented from interbreeding by responding to different mating dances
It is unlikely that the human opulation will give rise to a new species becaues
geographic isolation is unlikely to occur
What do the excretory, digestive, and respiratory systems have in common?
The contain specialized surfaces for exchange with the environment
A change in the body often triggers a response that counteracts the change. What is this known as?
process by which organisms maintain a relatively stable internal environment
An animals internal environment is...
the interstitial fluid that sorrounds the cells
What is the correct hierarchical order of tissue, organ, cell?
When you sprain your ankle, the "straps" of the tissue that hold the bones together are stretched and torn. What kind of tissue is damaged?
fibrous connective tissue
What forms a thick protective barrier that keeps bacteria out of the body?
stratifies squamous epithelium
The function of the large intestine, or colon
absorption of water
Basal metabolic rate
the energy needed o fuel essential body processes
Is this statement true or false-It is best to strive to have as little body fat as possible
Is glucose an essential nutrient?
Which of the following is not an essential nutrient-zinc, protein, vitamin c, calcium.
_______ are needed in the diet as components of teeth and bone, regulators of acid-base and water balance, and parts of certain enzymes.
A decreased intake of saturated fats will improve/hurt your health
What type of feeder are wolves, humans, elephants, hummingbirds, and termites?
Would a carnivorous animal or an herbivorous animal be more likely to have a longer digestive tract?
The herbivorous animal
Does an earthworm have any specialized respiratory structures?
The location of respiratory control centers is...
When you exhale, the diaphragm...
relaxes and arches
Why are bird lungs more efficient that human lungs
they have a one-way air flow system, rather than and in-out system
branch out from the bronchi and carry oxygen to the alveoli
An advantage of gas exchange in water as compared to water is...
the respiratory system will not dry out in water
In the blood, bicarbonate ions...
act as buffers to guard against PH changes
Smoking destroys the ___ in the respiratory passages.
Most oxygen is carried by the blood_____, most CO2 is carried by the blood_______.
attached to hemoglobin...in the form of bicarbonate ions.
What well known disease linked to smoking decreases the vital capacity of the lungs?
The _____ is the structure specialized for diffusion of gases and nutrients between the blood of the mother and the fetus.
Rhythmic stretcing of the arteries cause by heart contractions is...
Does a spider have an open or closed respiratory system?
Which of the following cannot move freely in and out of a capillary-sugar, O2, CO2, water, plasma proteins.
Heart valves function to
keep blood moving forward through the heart
Put the following in the correct order that traces electric impulses that trigger a heartbeat-atria,ventricles,AV node,pacemaker.
pacemaker,atria,AV node, ventricles.
A heart attack occurs when
a coronary artery is blocked
White blood cells
diease fighting cells in blood
If cells are not receiving enough oxygen, a hormone signlsthe bone marrow to produce more
What carries blood away from the heart
Blood moves most slowly in
In a fish, blood circulates through____ circuits, while in a mammal, it circulates through ___ circuits.
When exercising, _________________ allows greater blood flow to the skeletal muscles.
relaxation of muscle in walls of arterioles
A mouse is an ectotherm/endotherm
What is the coorect route of urine from the kidney to outside the body-bladder, ureter, urethra
ureter, bladder, urethra
Blood flows throught the hepatci portal vessel from the ___ to the ___.
A countercurrent heat exchanger allows an animal to
reduce heat loss
An advantage of excreting uric acid is that it ____, but a disadvantage is that it____.
saves water....costs energy
The main function of the kidney is to
regulate the body fluid composition
What is the first process when the kidney receives blood
On a cold day, blood vessels _____, reducing heat loss from the surface.
Filtrate is refined and concentrated by the processes of _______, forming the urine that leaves the body.
re-absorption and secretion
Nitrogenous waste products are moade from by-products of the breakdown of
The ____ system works closely with the endocrine system to control body processes.
An incease in blood sugar triggers the release of
Every ____ acts as a signal between cells
Researchers have found increased levels of hormones from the ____ glands in the blood of students preparing for final exams. These hormones are released in response to stress.
Insulin and glucagon work together to regulate
What is the role of a receptor in hormone action?
to enable a target cell to respond to a hormone
A hormone from the parathyroid glands works in opposition to a hormone from the ____ to regulate___.
thyroid gland....blood calcium
How is the level of thyroxine in the blood regulated?
Thyroxine and TSH inhibit secretion of TRH
Steroid hormones are produced only by the...
sex organs and adrenal cortex
Action potential is basically
flow of electricity along a neuron
A dendriteis the part of the neuron that carries signals toward the ____
The left cerebral hemispher contains association areas for ____
speech, language, and calculation.
A stimulus triggers an action potential by causing ______
sodium ions to leak into the neuron