what is the unit of force in the si system

ATI TEAS 7

TEAS 7 practice test free science

1. What is the unit of force in the SI system?

A. Newton (N)
B. Kilogram (kg)
C. Meter (m)
D. Second (s)

Correct answer: A

Rationale: The unit of force in the SI system is the Newton (N). It is defined as the amount of force required to accelerate a mass of one kilogram at a rate of one meter per second squared. In the SI system, force is measured in Newtons, not in kilograms, meters, or seconds. Choice B, Kilogram (kg), is incorrect because kilograms are units of mass, not force. Choice C, Meter (m), is incorrect because meters are units of length, not force. Choice D, Second (s), is incorrect because seconds are units of time, not force.

2. How does AIDS impair the immune system?

A. AIDS targets and destroys Helper T-Cells, preventing the activation of Cytotoxic T-Cells or B-Cells.
B. IgE stimulates mast cells to release excessive histamine.
C. IgE inhibits mast cells from releasing sufficient histamine.
D. Helper T-Cells deceive the body into attacking itself.

Correct answer: A

Rationale: AIDS targets and destroys Helper T-Cells, which play a crucial role in coordinating the immune response. By affecting these cells, AIDS prevents the activation of other important immune cells like Cytotoxic T-Cells or B-Cells. This disruption in the immune system's communication and response mechanisms leads to immune system failure and increased vulnerability to infections. Choices B and C are incorrect because they refer to the role of IgE in allergic reactions, which is not directly related to how AIDS impairs the immune system. Choice D is also incorrect as Helper T-Cells being destroyed in AIDS is not about deceiving the body into attacking itself, but rather the direct impact on immune system function.

3. When referring to blood vessel walls, the term 'atherosclerosis' describes:

A. The abnormal buildup of plaque within the arterial walls.
B. The inflammation of the inner lining of blood vessels.
C. The dilation and weakening of a blood vessel wall (aneurysm).
D. The normal process of blood vessel wall thickening with age.

Correct answer: A

Rationale: The correct answer is A: 'The abnormal buildup of plaque within the arterial walls.' Atherosclerosis is the process where plaque, consisting of fat, cholesterol, calcium, and other substances, accumulates within the arteries. This buildup can lead to the hardening and narrowing of arteries, reducing blood flow and potentially causing severe health issues like heart attacks and strokes. Choice B is incorrect because inflammation of the inner lining of blood vessels is known as vasculitis, not atherosclerosis. Choice C is incorrect as it describes an aneurysm, which is a dilation and weakening of a blood vessel wall, not atherosclerosis. Choice D is incorrect as it describes arteriosclerosis, a process of blood vessel wall thickening with age, which is different from atherosclerosis.

4. Why do emerging infectious diseases (EIDs) pose a significant public health threat?

A. Because they are well-understood by medical professionals
B. Because they are easily treatable with existing antibiotics
C. Because they are new, rapidly evolving, and can spread quickly
D. Because they primarily affect animals and not humans

Correct answer: C

Rationale: Emerging infectious diseases (EIDs) are a significant public health threat because they are characterized by being new or newly identified diseases that are rapidly evolving. These diseases can spread quickly within populations due to factors such as globalization, travel, urbanization, and changes in climate. EIDs often present challenges to medical professionals as they may not be well-understood initially, making it difficult to develop effective treatments or preventive measures. While some EIDs can be treatable with existing antibiotics, the rapid evolution of these diseases can lead to the development of drug resistance, further complicating treatment efforts. Additionally, EIDs are not limited to affecting animals; they can also have serious implications for human health and well-being. Therefore, the correct answer is that EIDs pose a threat because they are new, rapidly evolving, and can spread quickly. Choices A, B, and D are incorrect because EIDs are not well-understood initially, may develop drug resistance, and can affect humans significantly, not just animals.

5. Which of the following are the reproductive cells produced by meiosis?

A. Genes
B. Alleles
C. Chromatids
D. Gametes

Correct answer: D

Rationale: The correct answer is D. Gametes are the reproductive cells produced by meiosis. Meiosis is the cell division process that results in the formation of gametes, which are sperm cells in males and egg cells in females. Genes (A), alleles (B), and chromatids (C) are not the reproductive cells produced by meiosis. Genes are units of heredity, alleles are different forms of a gene, and chromatids are duplicated chromosomes involved in cell division.