what is the liquid found inside the cell

HESI RN

Biology Test

1. What is the liquid found inside the cell?

A. Plasma membrane
B. Cilia
C. Cytoplasm
D. Cytosol

Correct answer: D

Rationale: The correct answer is D, Cytosol. Cytosol is the liquid component of the cytoplasm where various cellular processes occur. Choices A, B, and C are incorrect because the plasma membrane is the outer boundary of the cell, cilia are hair-like structures on the cell surface, and cytoplasm is the jelly-like substance that contains organelles within the cell, not the liquid inside the cell.

2. Water is a polar molecule that can be:

A. cohesive and corrosive
B. cohesive and adhesive
C. electrostatic and ionic
D. repellent and attractive

Correct answer: B

Rationale: Water is a polar molecule due to an uneven distribution of electrons, allowing it to form hydrogen bonds. This property makes water both cohesive (attracted to itself) and adhesive (attracted to other substances). Choice A is incorrect because water is not corrosive; rather, it is a solvent. Choices C and D are incorrect as they do not describe the cohesive and adhesive properties of water.

3. What is the composition of the cellular membrane?

A. A bilayer of phospholipid molecules
B. A single layer of phospholipid molecules
C. Proteins that act as transport highways
D. Carbohydrates

Correct answer: A

Rationale: The cellular membrane is primarily composed of a phospholipid bilayer, which consists of two layers of phospholipid molecules. These molecules have a hydrophilic (water-attracting) head and hydrophobic (water-repelling) tail, creating a barrier that separates the internal cellular environment from the external surroundings. While proteins are embedded within this bilayer and act as transport channels, receptors, and structural support, carbohydrates are found on the outer surface of the membrane for cell recognition and signaling purposes. Therefore, the correct answer is a bilayer of phospholipid molecules.

4. Protein synthesis begins with a process known as transcription. Where does this process occur?

A. In the cytoplasm
B. In the nuclear envelope
C. In the ribosome unit
D. In the nucleus

Correct answer: D

Rationale: The correct answer is D: In the nucleus. Transcription, the initial step of protein synthesis, takes place in the nucleus where DNA is transcribed into mRNA. This mRNA then leaves the nucleus and enters the cytoplasm where translation occurs on the ribosomes. Choices A, B, and C are incorrect because transcription specifically occurs in the nucleus, not in the cytoplasm, nuclear envelope, or ribosome unit.

5. Which of the following processes produces nicotinamide adenine dinucleotide (NADH) and flavin adenine dinucleotide (FADH2) for the electron transport chain during cellular respiration?

A. Electron transport chain
B. Glycolysis
C. Citric acid cycle (the Krebs cycle)
D. None of these

Correct answer: C

Rationale: The correct answer is C, the citric acid cycle (the Krebs cycle). This cycle generates NADH and FADH2, which play a crucial role in providing electrons to the electron transport chain during cellular respiration. Choice A, the electron transport chain itself, is where NADH and FADH2 donate their electrons, not where they are produced. Choice B, glycolysis, produces NADH but not FADH2. Choice D, 'None of these,' is incorrect as the citric acid cycle specifically produces NADH and FADH2.