Biology- Final Exam

During blood clotting, a broken blood vessel triggers a cascade of factors that collectively reduce blood loss. In this example, the clotting factors are functioning as part of

a positive feedback loop.

Which of the following is one of the three important characteristics of an adaptation?

An adaptation improves an organism's survival in its environment.

Which of the following statements about sexual reproduction in humans is true?

Both parents contribute genes to the offspring.

Which of the locations highlighted in the following figure is the site of embryo implantation?

C

How closely related two DNA molecules, and the organisms from which they came, are is measured through

DNA sequence similarity

Which of the following statements about evolution is true?

Evolution can result in the addition or loss of traits in existing organisms.

Which of the following statements is true about adaptation?

It is the process by which natural selection improves the match between an organism and its environment over time.

Homeostatic pathways are a sequence of steps that reestablish the "normal state" of a living organism's internal environment. What determines the parameters of this "normal state"?

Organisms have a genetically predetermined set point that must be internally maintained.

Select the correct statement regarding natural selection and sexual selection.

Sexual selection is a form of natural selection that acts on phenotypes that give individuals advantages in mating opportunities.

Which of the following statements about human sperm and eggs is correct?

Sperm are much smaller than eggs

Some whales have teeth as embryos but do not as adults. What is the most likely explanation of this phenomenon?

Whales evolved from organisms that have teeth.

Breeding programs for farm-raised chickens result in a variety of unusual colors and feathers. Is this an example of evolution?

Yes; the change in chicken coloration is a genetic change in the population over time.

Evolution can be described as

a change in the genetic characteristics of a population of organisms over time.

A population of 8,250 mice occupies the sand dunes in a coastal area. A severe hurricane washes out several miles of sand dunes. As a result, only 50 mice remain. The population has experienced

a genetic bottleneck.

Evolution by natural selection allows species to

adjust to environmental changes

Which of the following would NOT be expected after a population undergoes geographic isolation?

an increase in gene flow

The hands of a human and the hands of a chimpanzee are similar in structure because humans

and chimpanzees share a recent common ancestor.

Disruptive selection operates whenever

both extremes of the phenotype are more successful.

Speciation

can result from geographic isolation

Close ecological interactions between two different species may lead to

coevolution

Two unrelated species evolving to look more similar due to environmental pressures is called

convergent evolution

Two different species may have similar features because of

descent from a common ancestor

Genetic variation is based on

differences in genotypes between the individuals in a population.

Convergent evolution occurs when natural selection causes distantly related organisms to

evolve similar structures in response to similar environmental challenges.

Both insects and humans evolved jointed legs to allow locomotion on land. These structures are considered analogous because insects and humans

evolved from different ancestors.

The fact that small, nonfunctioning hind legs are found in the skeletons of many snakes suggests that snakes

evolved from organisms with legs.

Both humans and whales evolved from a common ancestor. Although our forelimbs are quite different, they are made of the same bones. This is an example of a(n)

homologous structure.

Two populations that live __________ do NOT provide an example of geographic isolation.

in different parts of a small lake

Which of the following terms describes how the male sperm and the female egg typically fuse in animals?

internal fertilization

Natural selection

is the principle cause of evolutionary change

For which of the following would a mountain range most likely represent a geographic barrier that would block gene flow?

mice

Cardiac, smooth, and skeletal are all types of __________ tissue; they generate force to move structures within the body by contracting.

muscle

For a population to evolve, there must be genetic differences between organisms in that population. These differences arise by

mutation

New alleles emerge in a species via

mutation

Evolutionary changes occur when __________ acts upon populations containing individuals with genetic differences.

natural selection

Peppered moths are generally light in color and blend into the trunks of the trees on which they live. Populations of peppered moths found in areas where soot has blackened the tree trunks are dark in color. This example demonstrates

natural selection

The central driver of evolution is

natural selection

Using the biological species concept as a method of defining a species is NOT useful for

organisms known only from fossils.

Mature female eggs develop under the control of hormones within the

ovaries

Which of the following sequences places the direction traveled by an egg in the correct order?

ovary, oviduct, uterus, vagina

Sperm that are ejaculated from the body pass through the __________ last.

penis

Natural selection acts directly on __________ that increase survival and reproductive success.

phenotypes

When certain hormones are added to the uterus, they induce thickening in the cells lining its walls. Which of the following hormones is likely to be responsible for this change?

progesterone

Which of the following is a type of epithelial tissue?

skin

Evolution is

strongly supported by scientific evidence.

Epithelial, connective, muscle, and nervous are the four broad categories of animal body

tissues

During gestation, human development is divided into several stages called

trimesters

The diagram below shows the bone structure of a whale flipper and a bat wing. Which of the following suggests that these two structures are homologous rather than analogous?

Both the flipper and the wing contain five fingerlike bone projections.

Bacteria reproduce asexually, so scientists classify them based on

DNA sequence similarity and morphology

Which of the following must occur for one species to split into two or more species?

DNA sequences of genes must accumulate differences

Which of the following is true with regard to mutations?

Mutations appear without regard to environmental pressures.

Which of the following is NOT a step in the evolutionary process?

New genes are introduced into a population when members of that population mate with members of other species and produce offspring.

Which of the following statements accurately distinguishes tissues from organs?

Organs consist of multiple tissue types, whereas tissues consist of one or more cell types.

Whales have tiny thighbones embedded in the skin next to their pelvis. This is an example of

a vestigial structure.

During gene flow,

alleles exchange between populations.

A large population of animals is split in two by a physical barrier. Over time, the genetic makeup of the two resulting populations becomes more and more different until each population becomes a separate species. This is an example of

allopatric speciation

Convergent evolution produces

analogous traits

According to the biological species concept, a species is defined when individuals of the same species

are capable of interbreeding and producing fertile offspring.

Humans simulate the process of natural selection when they use ____________ to develop new varieties of crop plants that better meet the needs of farmers.

artificial selection

What is genetic drift?

chance evolutionary change occurring in small populations

What is biological evolution?

change in the inherited characteristics of a group of organisms over generations

In many predator-prey relationships, evolutionary change in the prey will result in evolutionary change in the predator, a phenomenon known as

coevolution

The fossil record

contains strong evidence that major new groups of organisms arose from previously existing organisms

The red-breasted nuthatch and the white-breasted nuthatch are similar in appearance and, in many regions of the United States, their ranges overlap. The two organisms do not interbreed. Based on this information, red-breasted and white-breasted nuthatches are

different species

Which of the following is NOT a mode of natural selection?

dormant selection

Two species live in the same area but breed in different parts of their habitat. These species are

ecologically isolated

Insulin is a protein hormone that helps cells use glucose found in the blood; it is produced by the pancreas and is circulated throughout the body by the circulatory system. In type 1 diabetes, insulin-producing cells in the pancreas are attacked and destroyed by the body's immune cells. This is an example of the

endocrine, digestive, circulatory, and immune systems affecting one another.

Although populations of North American apple maggot flies are not geographically isolated, they appear to be in the process of diverging into two new species. Which of the following could be causing speciation between two populations in the absence of geographic isolation?

feeding on two different types of food

Geographic isolation limits the __________ between separated populations of a species.

gene flow

Populations of a single species are connected by

gene flow

Asexual and sexual reproduction in animals is similar in that both

generate offspring that carry parental genes

How does geographic isolation lead to speciation?

geographic isolation allows mechanisms of evolution to cause genetic divergence

Which of the following is a collection of organs?

heart, lungs, and liver

Whale DNA is more similar to hippopotami DNA than to the DNA of any other mammal. This indicates that

hippos are whales' closest living relatives

Natural selection tends to

increase the commonality of characteristics that enhance survival and reproduction

An example of evolution that has been readily observed is

increased resistance of bacteria to an antibiotic that is used to kill them.

Gene flow between two populations

makes the genetic composition of the two populations more similar

Several related bird species live in a desert. One species is much smaller than the other species. This small species nests in holes in cacti. Because the bird is so small, it can easily squeeze between the spines of the cactus and create a well-protected nest. This is an example of

natural selection

The result of ____________ over evolutionary time spans is that alleles that allow organisms to survive and reproduce at a higher rate than other individuals become more common in the population.

natural selection

After about an hour of basking in the sun, the body temperature of the marine iguana reaches 37° C. Then it dives into the water to feed. Once in the water, its body temperature rapidly drops and the iguana must return to the rocks to warm up. This process is an example of

negative feedback

If you drink a large, sugary cola, your blood glucose levels will rise. Cells within your pancreas will respond by producing insulin, a hormone that allows glucose to enter the cells. As more glucose enters your cells, there will be less glucose in your bloodstream. Once the glucose level in your blood has dropped to a healthy concentration, your pancreas will cease to produce extra insulin. This is an example of a __________ loop.

negative feedback

Fossils found in deeper layers are __________ than fossils found in more shallow layers.

older

For homework, an instructor asks students to write a paragraph discussing how the mouth, stomach, and small intestines work together to process food and provide nutrients to the body. Which level of biological organization is the class studying?

organ systems

Which of the following sequences places the direction traveled by sperm in the correct order?

seminiferous tubules of the testes, vas deferens, penis

Individuals of the same species generally

share many common physical and behavioral characteristics.

Negative feedback

slows down or shuts off a process when a set point is reached

When individuals with intermediate values of an inherited phenotypic trait, like head circumference at birth, have an advantage over other individuals in the population, __________ is the apparent pattern of natural selection.

stabilizing selection

When robins lay a clutch of more than four eggs, their chicks are often malnourished because they have so many to feed. If the robins lay fewer than four eggs, they may not have any viable offspring. As a result, robins typically lay a clutch of four eggs. This is an example of

stabilizing selection

Why do human embryos develop gill slits?

the ancestor of humans had gills

The structure in the male reproductive tract that has a function similar to that of the female fallopian tubes is the

vas deferens

Gene flow occurs

when an individual migrates between two otherwise isolated populations of a species.

Immediately after fertilization, a(n) __________ will be found in the oviduct.

zygote

Select the correct statement regarding natural selection and sexual selection.

zygote

The cell resulting from the union of one sperm cell with one egg cell is known as a(n)

zygote.