A myocardial infarction affects which of the following blood vessels of the heart?
A. Coronary
B. Aorta
C. Pulmonary
D. Vena cava
A myocardial infarction affects the coronary blood vessels of the heart.
A myocardial infarction, commonly known as a heart attack, occurs when blood flow decreases or stops in the coronary artery of the heart, causing damage to the heart muscle 1.
Choice B is incorrect because the aorta is not a blood vessel of the heart.
The aorta is the main artery that carries oxygenated blood from the heart to the rest of the body.
Choice C is incorrect because the pulmonary blood vessels are not affected by a myocardial infarction.
The pulmonary blood vessels carry deoxygenated blood from the heart to the lungs.
Choice D is incorrect because the vena cava is not a blood vessel of the heart.
The vena cava is a large vein that carries deoxygenated blood from the body to the heart.
Therefore, the Correct Answer is A.
More Questions on TEAS 7 Science
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Q #1: Which of the following is the function of a totipotent cell?
A. Fights infectious diseases.
B. Aids in the maturation of sex cells.
C. Carries electrical impulses.
D. Develops into any kind of cell.
Answer Explanation
A totipotent cell can self-renew by dividing and develop into the three primary germ cell layers of the early embryo and into extra-embryonic tissues such as the placenta.
A fertilized egg is a totipotent stem cell and as such can develop into any specialized cell found in the organism.
Choice A is not correct because totipotent cells do not fight infectious diseases.
Choice B is not correct because totipotent cells do not aid in the maturation of sex cells.
Choice C is not correct because totipotent cells do not carry electrical impulses.
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Q #2: Which of the following is a group that can be measured against the experimental group?
A. Responding
B. Manipulated
C. Control
D. Variable
Answer Explanation
Control.
A control group is a group in an experiment that does not receive the treatment or manipulation being tested and is used as a benchmark to measure how the other tested subjects do.
The control group is used to minimize the effects of all variables except the independent variable.
This allows researchers to determine if changes in the dependent variable are due to the manipulation of the independent variable or if they are due to some other factor.
Choice A.
Responding is not the correct answer because it refers to the dependent variable, which is the variable that is being measured in an experiment.
Choice B.
Manipulated is not the correct answer because it refers to the independent variable, which is the variable that is being manipulated in an experiment.
Choice D.
Variable is not the correct answer because it refers to any factor that can change in an experiment and can include both independent and dependent variables.
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Q #3: Which of the following results in osteoporosis?
A. An increase in osteocyte activity while osteoclast activity continues at expected levels.
B. A decline in osteoclast activity while osteoblast activity continues at expected levels.
C. An increase in osteocyte activity while osteoblast activity reduces.
D. A decline in osteoblast activity while osteoclast activity continues at expected levels.
Answer Explanation
A decline in osteoblast activity while osteoclast activity continues at expected levels results in osteoporosis.
Osteoporosis is caused by an imbalance between the functioning of osteoclast and osteoblast cells.
Osteoblasts are responsible for forming new bone, while osteoclasts break down old bone.
If osteoblast activity declines while osteoclast activity continues at expected levels, this means that more bone is being broken down than is being formed, leading to a loss of bone density and an increased risk of osteoporosis.
Choice A is incorrect because an increase in osteocyte activity would not result in osteoporosis.
Osteocytes are mature bone cells that maintain the mineral concentration of the bone matrix.
Choice B is incorrect because a decline in osteoclast activity would not result in osteoporosis.
Osteoclasts break down old bone, so a decline in their activity would mean that less bone is being broken down.
Choice C is incorrect because an increase in osteocyte activity would not result in osteoporosis.
As mentioned earlier, osteocytes are mature bone cells that maintain the mineral concentration of the bone matrix.
