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Which of the following is an efferent neuron that is responsible for releasing a neurotransmiter that stimulates a muscle cell to contract?

A. Motor neuron

B. Interneuron

C. Sensory neuron

D. Neuroglia

Answer Explanation:

An efferent neuron that is responsible for releasing a neurotransmitter that stimulates a muscle cell to contract is a motor neuron ². Motor neurons carry signals from the brain to the peripheral nervous system in order to initiate an action. The neurotransmitter acetylcholine (ACh) is released by motor neurons at the neuromuscular junction in skeletal muscle, causing the muscle to contract ³.

The other options are incorrect because they do not accurately describe the type of neuron responsible for releasing a neurotransmitter that stimulates a muscle cell to contract. Interneurons are found within the central nervous system and facilitate communication between sensory and motor neurons. Sensory neurons carry information from sensory receptors to the central nervous system. Neuroglia are support cells for neurons and do not transmit nerve impulses.

Therefore, the Correct Answer is A.

More Questions on TEAS 7 Science

  • Q #1: Experiments cannot validate hypotheses, only falsify them. The statement above can be restated in which of the following ways?  

    A. a. Until disproved, an explanation for an observation is valid.

    B. b. Certain concepts cannot be subjected to direct experimentation.

    C. c. A hypothesis that has not been falsified remains provisional.

    D. d. Proving a hypothesis exempts it from further testing

    Answer Explanation

     

    The statement "Experiments cannot validate hypotheses, only falsify them" can be restated as "A hypothesis that has not been falsified remains provisional." This means that a hypothesis is considered valid until it is disproved by experimental evidence. However, even if a hypothesis has not been falsified, it is still considered provisional and subject to further testing and scrutiny.

    a."Until disproved, an explanation for an observation is valid" is similar to the correct answer but does not capture the provisional nature of a hypothesis.

    b."Certain concepts cannot be subjected to direct experimentation" is not a restatement of the original statement.

           d. "Proving a hypothesis exempts it from further testing" is incorrect because no hypothesis can be definitively proven and all hypotheses are subject to further testing and         scrutiny.

  • Q #2: Which of the following layers of skin lack blood vessels?

    A. Papillary

    B. Epidermis

    C. Reticular

    D. Hypodermis

    Answer Explanation

    The layer of skin that lacks blood vessels is the epidermis. The epidermis is the thin outer layer of the skin and does not have any blood vessels within it. It is composed of keratinized, stratified squamous epithelium and is made of four or five layers of epithelial cells, depending on its location in the body.

    The other options are not correct because they do contain blood vessels. The papillary layer is part of the dermis, which contains blood vessels. The reticular layer is also part of the dermis and contains blood vessels . The hypodermis is a layer below the dermis and also contains blood vessels.

  • Q #3: Punnet Square An organism with an unknown genotype is crossed with another organism that shows the recessive trait (aa). The Punnet square below shows the results. Which of the following is the unknown genotype?     Unknown Unkonwn a Aa aa a Aa aa

    A. a

    B. Aa

    C. aa

    D. AA

    Answer Explanation

    The unknown genotype is Aa. This can be inferred from the Punnet square, which shows that half of the offspring are Aa and half are aa. This indicates that the unknown parent must have one dominant allele (A) and one recessive allele (a), making its genotype Aa.

    The other options are not correct because they do not match the results shown in the Punnet square. If the unknown genotype was aa or AA, all of the offspring would have the same genotype as their parent. If the unknown genotype was a, it would not be a valid genotype as it only has one allele.

  • Q #4: Emphysema caused by damage to alveoli from toxins and pollutants is likely to result in the body having difficulty performing which of the following actions?

    A. Releasing histamine and acetylcholine

    B. Exchanging oxygen and carbon dioxide

    C. Absorbing food

    D. Producing enzymes

    Answer Explanation

    Emphysema is a lung condition that is caused by damage to the alveoli, the tiny air sacs in the lungs where gas exchange occurs. When the alveoli are damaged, the body has difficulty exchanging oxygen and carbon dioxide. This can lead to shortness of breath and other respiratory problems. The other options are not directly related to the function of the alveoli or the effects of emphysema.

  • Q #5: A researcher wants to gather data on the average wing strength of all birds found in the American Northwest. The researcher only has one small net, so all large birds were excluded from the study. The researcher's results were different than expected, but he believes his data include enough birds to estimate the strength of all birds. For which of the following reasons should this data be rejected?

    A. Data contradict the control group

    B. Data were different than expected

    C. Data are biased by the methodology

    D. Data cannot be displayed graphically

    Answer Explanation

    The correct answer is c. Data are biased by the methodology. The researcher's data should be rejected because they are biased by the methodology used to gather them. By only using a small net, the researcher excluded all large birds from the study. This means that the data do not accurately represent the average wing strength of all birds found in the American Northwest.

    A. The data contradicting the control group is not a reason to reject the data in this case.

    B. The data being different than expected is not a reason to reject the data in this case.

    D. The data not being able to be displayed graphically is not a reason to reject the data in this case.

  • Q #6: Which of the following is the process in which an ovarian follicle matures and releases a reproductive egg?

    A. Oogenesis

    B. Menstruation

    C. Ovulation

    D. Fertilization

    Answer Explanation

    Ovulation is the process in which an ovarian follicle matures and releases a reproductive egg. During ovulation, the egg is released from the ovary and travels down the fallopian tube where it may be fertilized by sperm.

    The other options are not processes in which an ovarian follicle matures and releases a reproductive egg. Oogenesis is the process of egg cell formation, menstruation is the shedding of the uterine lining, and fertilization is the fusion of an egg and sperm to form a zygote.

  • Q #7: Which of the following best describes the result of using a catalyst in a chemical reaction?

    A. A more desirable product is often formed.

    B. The reaction is completed in a shorter amount of time.

    C. A greater amount of heat energy is released by the reaction.

    D. The yield of product is increased.

    Answer Explanation

    The result of using a catalyst in a chemical reaction is that the reaction is completed in a shorter amount of time ¹. A catalyst is a chemical substance that affects the rate of a chemical reaction by altering the activation energy required for the reaction to proceed ¹. This process is called catalysis ¹. A catalyst provides an alternative pathway for the reaction, one that has a lower activation energy than the uncatalyzed pathway .

    The other options are not correct because they do not accurately describe the result of using a catalyst in a chemical reaction. A more desirable product is not necessarily formed, a greater amount of heat energy is not necessarily released by the reaction, and the yield of product is not necessarily increased as a result of using a catalyst.

  • Q #8: Parasitic worm infestation is hypothesized to be damaging to the host. However, scientists have recently discovered that worm infestation can relieve the effects of certain autoimmune disorders. In which of the following ways should the hypothesis be modified, given the new findings?

    A. Worm infestation prevents the body from immune malfunction.

    B. Worm infestation reduces the severity of certain autoimmune disorders.

    C. Lack of worm infestations is the cause of some autoimmune disorders.

    D. Worm infestations exacerbate the body's immune reaction.

    Answer Explanation

    Given the new findings that worm infestation can relieve the effects of certain autoimmune disorders, the hypothesis should be modified to state that worm infestation reduces the severity of certain autoimmune disorders.

    This option best reflects the new information and suggests a potential benefit of worm infestation in relation to autoimmune disorders. The other options do not accurately reflect the new findings and do not provide a clear modification to the hypothesis.

  • Q #9: Which of the following structures is present in both prokaryotic and eukaryotic cells?

    A. Endoplasmic reticulum

    B. Cell membrane

    C. Chloroplast

    D. Golgi apparatus

    Answer Explanation

    The structure that is present in both prokaryotic and eukaryotic cells is the cell membrane ². The cell membrane is a thin layer that surrounds the cell and separates its internal environment from the external environment ². It is composed of a lipid bilayer and proteins and regulates the movement of substances into and out of the cell ².

    The other options are not correct because they are not present in both prokaryotic and eukaryotic cells. The endoplasmic reticulum, chloroplast, and Golgi apparatus are organelles that are only found in eukaryotic cells ².

  • Q #10: Which of the following describes a genetic mutation that results in uncontrolled division of a single cell within the body?

    A. Cancer

    B. Gene therapy

    C. Stem cell

    D. Translation

    Answer Explanation

    A genetic mutation that results in uncontrolled division of a single cell within the body describes cancer ¹. Cancer is a disease of uncontrolled cell division ¹. Its development and progression are usually linked to a series of changes in the activity of cell cycle regulators ¹. In most cases, these changes in activity are due to mutations in the genes that encode cell cycle regulator proteins ¹.

    The other options are not correct because they do not accurately describe a genetic mutation that results in uncontrolled division of a single cell within the body. Gene therapy, stem cells, and translation are not processes that result in uncontrolled cell division.