vaccines work by stimulating the immune system to develop memory without causing full blown illness what type of molecule in a vaccine typically trigg
Logo

Nursing Elites

ATI TEAS 7

ATI TEAS 7 science review

1. How do vaccines stimulate the immune system to develop memory without causing full-blown illness? What type of molecule in a vaccine typically triggers the immune response?

Correct answer: D

Rationale: Vaccines work by triggering the immune system to develop memory without causing illness. They typically contain antigens, which are specific molecules from the pathogen. These antigens stimulate the immune system to produce a targeted immune response without causing full-blown sickness. By presenting these antigens, vaccines help the immune system create memory cells that remember the pathogen. This memory allows the immune system to respond more effectively if it encounters the pathogen in the future. Choices A, B, and C are incorrect because vaccines do not typically contain toxins, live pathogens, or inactivated forms of the pathogen. Instead, vaccines primarily rely on specific molecules (antigens) to induce an immune response.

2. What is the unit of measurement for density?

Correct answer: A

Rationale: Density is defined as mass per unit volume. The most commonly used unit for density in the metric system is grams per liter (g/L). Kilograms per cubic meter (kg/m³) is also a common unit for density, but grams per liter is more frequently used in everyday measurements. Pounds per square inch (psi) is a unit of pressure, not density. Newtons per meter (N/m) is a unit of force per unit length, not density.

3. During which of the following stages does crossing over occur?

Correct answer: B

Rationale: Crossing over occurs during Prophase I of meiosis. This stage is specifically associated with genetic recombination, where homologous chromosomes exchange genetic material. This process contributes to genetic diversity by creating new combinations of alleles. Choices A, C, and D are incorrect. In mitosis, crossing over does not occur as it involves the separation of replicated chromosomes. Meiosis Prophase II is focused on the reformation of nuclei and does not involve crossing over. Interphase is a stage where the cell prepares for division and is not associated with crossing over.

4. Which of the following best defines the term amphoteric?

Correct answer: B

Rationale: An amphoteric substance can act as both an acid or a base depending on the environment. It can donate a proton (act as an acid) or accept a proton (act as a base), showing versatility in its behavior. Choice A is incorrect as it describes an electrolyte rather than an amphoteric substance. Choice C is incorrect as it defines an acid based on the Brønsted-Lowry Acid-Base Theory. Choice D is incorrect as it specifically refers to a substance donating a proton in a neutralization reaction, not capturing the dual behavior of an amphoteric substance.

5. Which of the following is an example of a chemical change?

Correct answer: C

Rationale: Rusting iron is an example of a chemical change because it involves a chemical reaction where iron reacts with oxygen in the presence of water to form iron oxide (rust). This reaction results in a change in the chemical composition of the iron, unlike dissolving sugar in water, boiling water, or crushing ice, which are physical changes. Dissolving sugar in water is a physical change as sugar molecules remain unchanged but disperse in water. Boiling water is also a physical change as water changes its state from liquid to gas due to heat. Crushing ice is a physical change as the solid ice changes its physical form without altering its chemical composition.

Similar Questions

What is the relationship between the frequency and period of a wave?
Which of the following is NOT a common symptom of pregnancy?
What is the term for a substance that can act as both a proton donor and a proton acceptor?
The adaptive immune system has two main branches: humoral and cell-mediated immunity. Which type of immune cell is primarily responsible for antibody production?
What is the primary function of the atrioventricular (AV) node within the heart?

Access More Features

ATI TEAS Premium Plus
$149.99/ 90 days

  • Actual ATI TEAS 7 Questions
  • 3,000 questions with answers
  • 90 days access

ATI TEAS Basic
$99/ 30 days

  • 3,000 Questions with answers
  • 30 days access

Other Courses