what is the golgi apparatus

ATI TEAS 7

ati teas 7 science

1. What is the Golgi apparatus?

A. A network of tubules that transport proteins and lipids throughout the cell
B. A sac-like structure that stores water and nutrients
C. The site of protein synthesis
D. The site of protein modification and packaging

Correct answer: D

Rationale: The Golgi apparatus is an organelle in the cell responsible for modifying, sorting, and packaging proteins and lipids for transport to their final destinations. It consists of a series of flattened sacs called cisternae and plays a crucial role in processing proteins synthesized in the endoplasmic reticulum. Option A is incorrect because the network of tubules that transport proteins and lipids throughout the cell is typically associated with the endoplasmic reticulum. Option B is incorrect as the structure described is more characteristic of a vacuole, which stores water and nutrients. Option C is incorrect as protein synthesis primarily occurs in the ribosomes, not the Golgi apparatus.

2. What is the SI unit of measurement for momentum?

A. Newton (N)
B. Kilogram-meter per second (kg·m/s)
C. Joule (J)
D. Newton-second (N·s)

Correct answer: B

Rationale: The correct SI unit of measurement for momentum is kilogram-meter per second (kg·m/s). Momentum is a vector quantity that is calculated by multiplying an object's mass (in kilograms) by its velocity (in meters per second), resulting in the unit kg·m/s. This unit represents the quantity of motion an object possesses, taking into account both the mass and velocity of the object. Choice A, Newton (N), is the unit of force, not momentum. Choice C, Joule (J), is the unit of energy, not momentum. Choice D, Newton-second (N·s), is the unit of impulse, not momentum.

3. What is the purpose of an electrocardiogram?

A. Indicate the rate of blood flow
B. Display the heart's rate and rhythm
C. Identify a person's blood group type
D. Determine cell type in a blood sample

Correct answer: B

Rationale: An electrocardiogram (ECG or EKG) is used to measure and display the heart's rate and rhythm. It provides valuable information about the electrical activity of the heart, allowing healthcare providers to assess the heart's health, detect abnormalities in the heart's rhythm, and diagnose various cardiac conditions. Choices A, C, and D are incorrect. Choice A is incorrect because an ECG does not indicate the rate of blood flow but rather focuses on the heart's electrical activity. Choice C is incorrect because identifying a person's blood group type is typically done through blood typing tests, not ECG. Choice D is incorrect because determining cell type in a blood sample is unrelated to the purpose of an ECG.

4. Which hormone is released by the adrenal glands in response to stress?

A. Insulin
B. Cortisol
C. Adrenaline
D. Glucagon

Correct answer: C

Rationale: Adrenaline is the correct answer. It is released by the adrenal glands in response to stress to prepare the body for the 'fight or flight' response. Adrenaline increases heart rate, dilates airways, and mobilizes energy stores to help the body deal with the perceived threat. Insulin (Choice A) is produced by the pancreas to regulate blood sugar levels, not in response to stress. Cortisol (Choice B) is another hormone released by the adrenal glands in response to stress, but it primarily helps regulate metabolism and immune response. Glucagon (Choice D) is also produced by the pancreas to increase blood sugar levels when they are low, not by the adrenal glands in response to stress.

5. After exposure to a pathogen, the immune system develops memory. What type of immune cell is responsible for this immunological memory?

A. B cells
B. T cells (specifically memory T cells)
C. Phagocytes
D. Natural killer cells

Correct answer: A

Rationale: B cells are responsible for immunological memory. Memory B cells, a type of B cells, retain a 'memory' of specific pathogens, enabling them to rapidly produce antibodies upon re-exposure. This rapid antibody production facilitates a quicker and more effective immune response. Although memory T cells also contribute to immunological memory by mounting a swift and robust immune response upon re-exposure to the pathogen, it is primarily memory B cells that play a crucial role in producing antibodies. Phagocytes are important immune cells involved in engulfing and digesting pathogens, while natural killer cells are primarily responsible for recognizing and eliminating abnormal cells, such as virus-infected cells or tumor cells. However, when it comes to immunological memory and antibody production, B cells are key players.