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Biology MCAS Questions and Answers Latest Updated
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Biology MCAS Questions and Answers Latest Updated
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Biology MCAS Questions and AnswersLatest Updated
Collagen is found is connective tissue throughout the human body. Collagen is made of
three amino acid chains that are twisted around each other. What BEST explains why
collagen is classified as a protein? - ANSWER-It is made up of amino acids
In tigers, the allele for orange fur is dominant to the allele for white fur. If two
heterozygous tigers mate and produce offspring, what is the probability of an individual
offspring having white fur? - ANSWER-1/4
Information is detected by the eye and sent to the brain by what structures? - ANSWER-
sensory neurons
A scientist is trying to determine how closely related two species of plants are. What
would be useful for the scientist to compare? - ANSWER-the genetic sequences of the
plants
S. epidermis can sometimes infect wounds. The symptoms of the infection include
swelling, pain, pus, skin that is warm to the touch, and redness at the infection site.
Based on the symptoms, which human body systems work together to restore
homeostasis? - ANSWER-circulatory system and immune system
What is a characteristic that distinguishes viruses from B. thetaiotaomicron and S.
epidermis? - ANSWER-viruses are unable to reproduce outside of the host cells.
What best explains how antibiotic resistance spreads through some populations of S.
epidermidis? - ANSWER-Some S. epidermidis cells exposed to antibiotics survive and
pass their genes on to their offspring
What describes one way B. thetaiotaomicron helps in digestion? - ANSWER-It breaks
down polysaccharides into simpler sugars.
The human body contains diverse types of bacteria. Scientists estimate that the
average healthy adult human body is home to at least 10,000 species of bacteria. In
fact, there are about 10 times more bacterial cells than human cells in the human body.
Many bacterial populations are important to the normal functioning of human body
systems. For example, some bacteria in the digestive system produce substances the
human body cannot produce. These substances help the body break down and absorb
nutrients. However, bacteria that help the human body in one location can cause
serious illness if introduced to a different part of the body. - ANSWER-Two bacteria
found in the human body are B. thetaiotaomicron and S. epidermidis
B. thetaiotaomicron - ANSWER--typically lives in the small intestine
,-produces hundreds of enzymes that help break bonds in complex carbohydrates
-2nd most frequently encountered Bacteroides
-GNR or coccabacili
-bile esculin tolerant
-indole (+)
- catalase (+)
S. epidermidis - ANSWER--typically lives on the skin
-can cause serious infections if it enters the bloodstream
-some populations of S. epidermidis have antibiotic resistance
- the most common cause of foreign body infections due to its ability to produce biofilms
(polysaccharide)
S. epidermidis can sometimes infect wounds. The symptoms of the infection include
swelling, pain, pus, skin that is warm to the touch, and redness at the infection site.
Based on the symptoms, which human body systems work together to restore
homeostasis? - ANSWER-circulatory system and immune system
What is a characteristic that distinguishes viruses B. thetaiotaomicron and S.
epidermidis? - ANSWER-Viruses are unable to reproduce outside of the host cells.
What BEST explains how antibiotic resistance spreads through some populations of S
epidermidis? - ANSWER-Some S epidermidis cells exposed to antibiotics survive and
pass their genes on to their offspring.
A population of S. epidermidis decreases the population sizes of other types of bacteria
on the skin.
A. Describe one way decreasing the population sizes of other bacteria on the skin helps
the S. epidermidis population.
B. Identify the process that S. epidermidis cells use to reproduce.
C. Describe TWO similarities between the process that skin cells use for cell division
and the process that you identified in part (B).
When S. epidermidis moves from the skin into the body, it behaves like an invasive
species entering a new ecosystem.
D. Will S. epidermidis population size decreases, increase, or stay the the same after
the bacteria enter the body? Using your knowledge of invasive species, explain your
answer. - ANSWER-A. One way decreasing the size of other bacteria populations on
the skin helps the S. epidermidis population is by increasing the amount of resources
such as food and space that otherwise would be competed for by all the bacteria on the
skin.
B. The process S. epidermidis cells use to reproduce is binary fission (asexual
reproduction).
,C. Two similarities between the process skin cells use for cell division and the process
S epidermidis uses for cell division are that - 1. before cell division in both, DNA is
replicated; and 2. The method of reproduction in both is asexual, and one cell splits into
two cells.
D. The S. epidermidis population size will increase. Like an invasive species, when
introduced to a new area where they are not meant to be, they can reproduce out of
control, as they have little to no competition or natural enemies.
A high respiratory rate usually indicates that a person's body needs more ________. -
ANSWER-oxygen
A particular species of moth can have green or yellow scales on its wings. The scale
color is controlled by a single gene with two alleles, the green allele and the yellow
allele. When moths that are homozygous for green scales are mated with moths that
are homozygous for yellow scales, 100% of the offspring have green scales. Based on
this information, how do the alleles for scale color interact? - ANSWER-the green allele
is dominant to the yellow allele.
The dusky rattlesnakes that live in the mountains of Mexico have a variety of color
patterns, body shapes, and behaviors. A recent study of dusky rattlesnake DNA
concluded that there is a lot of genetic diversity within the species. What most likely
describes this great genetic diversity in dusky rattlesnakes? - ANSWER-Rattlesnake
populations inhabited various types of niches over time.
Compare a bacterial cell and an animal in regards to whether or not they have a cell
membrane, lysosomes, and a cell wall. - ANSWER-A bacterial cell has a cell membrane
and a cell wall, but has no lysosomes.
An animal cell has a cell membrane and lysosomes, but no cell wall.
Early explorers in the United States often observed huge flocks of passenger pigeons.
In the 1800s, hunters began netting and shooting the birds in huge numbers to sell as
food. In 1914, passenger pigeons were declared extinct when the last one died at the
Cincinnati zoo. Why did passenger pigeons become extinct? - ANSWER-Hunters killed
passenger pigeons faster than the pigeons could reproduce.
A female Hymenoepimecis wasp will temporarily paralyze a spider and then lay an egg
on the spider's abdomen. After the paralysis wears off, the spider resumes its normal
activity. When the egg hatches, the larva grows by sucking its required nutrients from
the spider. What type of relationship exists between the spider and the
Hymenoepimecis wasp? - ANSWER-parasitism (Parasitism is a type of symbiotic
relationship in which one organism benefits at the expense of another. The species that
benefits is called the parasite, while the one that is harmed is called the host. Over half
of all known species are parasites. Parasites are found in all biological kingdoms.
, An aquarium contains two brine shrimp populations, Artemia sinica and Artemia
franciscana. An individual from the A. sinica population and an individual from the A.
franciscana population are unable to do what? - ANSWER-produce fertile offspring with
each other
Fossilized remains of prehistoric mastodons show anatomical similarities to modern-day
elephants. These similarities provided the first evidence that mastodons were related to
modern-day elephants. What is the best additional evidence that mastodons were
related to elephants? - ANSWER-Mastodon tissues contained protein sequences similar
to those of modern-day elephants.
Lipids, carbohydrates, and DNA all exist in human cells as long molecular chains. What
describes how DNA differs from lipids and carbohydrates? - ANSWER-Only DNA
contains genetic informaton
Diatoms are marine organisms with unique cell walls that contain the element silicon.
which of the following are two common elements found in the cells of diatoms? -
ANSWER-nitrogen and phosphorus
Each summer, up to 40% of the lobsters in a certain area lose one of their claws due to
injury. By late fall, the missing claw usually begins to grow back. What describes the
process by which lobsters grow new claws? - ANSWER-Mitotic cell division adds new
cells to rebuild the lobster's claw.
Some populations of Atlantic tomcod fish have an allele that makes the fish resistant to
toxic pollutants called PCBs. Tomcod populations in several rivers were analyzed for
the presence of this allele. Each river had varying levels of PCB pollution. What would
support the conclusion that natural selection is influencing the presence of this allele in
the tomcod population? - ANSWER-The rivers with high PCB levels have larger
percentages of tomcod with this allele than the rivers without PCBs
What describes how enzymes affect chemical reactions? - ANSWER-they speed up the
rate of reactions
What describes why introduced species often threaten native species in an ecosystem?
- ANSWER-introduced species often lack natural predators in their new environment
For a new liver cell to form, DNA replication is necessary because it ensures that the
newly formed cell has ______________________. - ANSWER-an identical copy of the
original cell's DNA
In what way does the plasma membrane regulate the entry of molecules into a cell? -
ANSWER-the membrane only allows certain molecules to move into the cell
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