Gen Bio 1011 Practice Exam

What is the primary function of the cell membrane?

• A) Energy production

• B) Protein synthesis

• C) Selective permeability

• D) Genetic material storage

Answer explanation

The primary function of the cell membrane is selective permeability, allowing certain substances to pass while blocking others, thus maintaining the cell's internal environment.

Tags

NGSS.MS-LS1-2

Which part of the phospholipid molecule is hydrophilic?

• A) Tail

• B) Head

• C) Both A and B

• D) Neither A nor B

Answer explanation

The hydrophilic part of a phospholipid molecule is the head, which is attracted to water. In contrast, the tail is hydrophobic and repels water. Therefore, the correct answer is B) Head.

In which type of environment do organisms need more unsaturated fats in their membranes to maintain fluidity?

• A) Hot

• B) Cold

• C) Dry

• D) Acidic

Answer explanation

Organisms in cold environments require more unsaturated fats in their membranes to maintain fluidity. Unsaturated fats prevent the membranes from becoming too rigid, allowing for proper function at lower temperatures.

What is the main characteristic of passive transport?

• A) Requires energy

• B) Moves against the concentration gradient

• C) Moves with the concentration gradient

• D) Involves vesicles

Answer explanation

The main characteristic of passive transport is that it moves substances with the concentration gradient, meaning from areas of higher concentration to lower concentration, without requiring energy.

Which of the following processes requires energy?

• A) Osmosis
  

• B) Facilitated diffusion

• C) Active transport
  

• D) Simple diffusion

  
  

Answer explanation

Active transport requires energy to move substances against their concentration gradient, while osmosis, facilitated diffusion, and simple diffusion occur passively without energy input.

What is the role of cholesterol in the cell membrane? (Not too important to know)

• A) Increase membrane fluidity

• B) Decrease membrane fluidity

• C) Provide energy

• D) Act as a receptor

Answer explanation

Cholesterol plays a crucial role in maintaining membrane fluidity. It helps to stabilize the membrane structure, preventing it from becoming too rigid or too fluid, thus increasing overall membrane fluidity.

Which type of transport involves the movement of large molecules into the cell?

• A) Diffusion

• B) Exocytosis

• C) Endocytosis

• D) Osmosis

Answer explanation

Endocytosis is the process that allows large molecules to enter the cell by engulfing them in a membrane. In contrast, diffusion, exocytosis, and osmosis involve smaller molecules or the removal of substances from the cell.

What is the primary function of ribosomes?

• To store genetic information.

• The primary function of ribosomes is to synthesize proteins.

• To transport nutrients within the cell.

• To produce energy for cellular activities.

Answer explanation

The primary function of ribosomes is to synthesize proteins, which are essential for various cellular functions. The other options do not accurately describe the role of ribosomes in the cell.

What are the products of glycolysis?

• A) 2 ATP, 2 NADH, and 2 pyruvate

• B) 2 ATP, 2 FADH2, and 2 acetyl-CoA

• C) 4 ATP, 2 NADH, and 2 pyruvate

• D) 2 ATP, 4 NADH, and 2 glucose

Answer explanation

Glycolysis produces 2 ATP, 2 NADH, and 2 pyruvate from one glucose molecule. Option A correctly lists these products, while the other options include incorrect products or quantities.

Tags

NGSS.HS-LS1-7

Where does the citric acid cycle occur in eukaryotic cells?

• A) Cytoplasm

• B) Nucleus

• C) Mitochondria

• D) Endoplasmic reticulum

Answer explanation

The citric acid cycle, also known as the Krebs cycle, occurs in the mitochondria of eukaryotic cells. This is where aerobic respiration takes place, utilizing acetyl-CoA to produce energy.

Tags

NGSS.HS-LS2-3

NGSS.HS-LS2-5