which of the following molecules is an important component of the plasma membrane
Logo

Nursing Elites

HESI A2

HESI A2 Practice Test Biology

1. Which of the following molecules is an important component of the plasma membrane?

Correct answer: A

Rationale: Phospholipids are indeed a crucial component of the plasma membrane. They have a unique structure with hydrophilic heads and hydrophobic tails, which allows them to form the lipid bilayer of the membrane. Steroids, sugars, and amino acids are not primary components of the plasma membrane. Steroids are a different type of lipid, sugars are often found in glycoproteins on the membrane surface, and amino acids are the building blocks of proteins, some of which are membrane proteins, but not the membrane itself.

2. Which type of passive transport uses proteins that change shape to move a target molecule through the membrane?

Correct answer: B

Rationale: The correct answer is B: Carrier proteins. Carrier proteins are involved in facilitated diffusion, a type of passive transport where specific target molecules are moved across the membrane with the help of proteins that change shape. These carrier proteins bind to the target molecule on one side of the membrane, undergo a conformational change, and then release the molecule on the other side. This process is crucial for the selective transport of certain molecules that cannot pass through the membrane by simple diffusion. Choices A and C are incorrect because diffusion and channel proteins do not involve proteins that change shape to transport target molecules selectively. Choice D is incorrect as carrier proteins fit the description provided in the question.

3. Which organelle is the site of photosynthesis in plant cells?

Correct answer: B

Rationale: The correct answer is B: Chloroplasts. Chloroplasts are responsible for conducting photosynthesis in plant cells. They contain chlorophyll, a pigment that captures light energy and converts it into chemical energy through the process of photosynthesis. Mitochondria (choice A) are known as the powerhouse of the cell and are involved in cellular respiration, not photosynthesis. Ribosomes (choice C) are responsible for protein synthesis. The endoplasmic reticulum (choice D) is involved in protein and lipid synthesis and transport within the cell, not photosynthesis.

4. Athletes are often concerned with the question of what they need in their diets to increase muscle mass and strength. What biologic molecule would you recommend that would accomplish this?

Correct answer: B

Rationale: Proteins are essential for building and repairing muscle tissue. They contain amino acids, which are the building blocks of muscles. Athletes looking to increase muscle mass and strength should focus on consuming adequate amounts of high-quality proteins in their diets. Carbohydrates provide energy for workouts, lipids are important for overall health but do not directly contribute to muscle building, and nucleic acids are involved in genetic activities rather than muscle growth.

5. Prokaryotic cells:

Correct answer: B

Rationale: Prokaryotic cells do not have a nucleus or membrane-bound organelles. One characteristic feature of prokaryotic cells is the presence of a capsule, which is a protective layer outside the cell wall. This capsule helps the prokaryotic cell adhere to surfaces, evade the host immune system, and protect against desiccation. Choice A is incorrect because prokaryotic cells lack a nucleus. Choice C is incorrect as prokaryotic cells do not have membrane-bound organelles. Choice D is incorrect as prokaryotic cells can move using structures like flagella or pili.

Similar Questions

Where is the ovary located in a flowering plant?
In an example of a male with hemophilia and a female carrier, what percentage of the offspring is predicted to be carriers only?
Select the option that best shows complementary base pairing in DNA:
How many phases are there in the process of mitosis?
In a phospholipid molecule, the head:

Access More Features

HESI A2 Basic
$89/ 30 days

  • 3,000 Questions with answers
  • 30 days access

HESI A2 Premium
$129.99/ 90 days

  • Actual HESI A2 Questions
  • 3,000 questions with answers
  • 90 days access

Other Courses