Free BACE Cells Questions and Answers — Questions and Answers
Question 1: Which of the following structures is responsible for energy production in eukaryotic cells?
- Nucleus
- Ribosome
- Mitochondria (Correct answer)
- Lysosome
Correct answer: Mitochondria
Mitochondria are often referred to as the 'powerhouses' of the cell because they are responsible for generating most of the cell's supply of adenosine triphosphate (ATP), which is used as a source of chemical energy. This vital process, known as cellular respiration, occurs within the mitochondria of eukaryotic cells. Other organelles like the nucleus, ribosome, and lysosome have different primary functions.
Question 2: What is the primary function of the ribosome in the cell?
- Synthesizing DNA
- Producing proteins (Correct answer)
- Storing lipids
- Breaking down carbohydrates
Correct answer: Producing proteins
The ribosome is a crucial cellular organelle responsible for protein synthesis, a process also known as translation. It reads messenger RNA (mRNA) sequences and uses this genetic information to assemble amino acids into functional proteins. This function is fundamental for all cellular activities, as proteins perform a vast array of roles from structural support to enzymatic catalysis.
Question 3: Which component of the cell membrane is primarily responsible for selective permeability?
- Phospholipids (Correct answer)
- Carbohydrates
- Nucleic acids
- Proteins
Correct answer: Phospholipids
Phospholipids are the primary structural components of the cell membrane, forming a bilayer. Their amphipathic nature, with hydrophilic heads and hydrophobic tails, creates a barrier that selectively regulates the passage of substances into and out of the cell. This phospholipid bilayer acts as the fundamental gatekeeper, allowing small, nonpolar molecules to pass while restricting larger or charged molecules.
Question 4: In what phase of the cell cycle does DNA replication occur?
- G1 phase
- S phase (Correct answer)
- G2 phase
- M phase
Correct answer: S phase
The S phase, or synthesis phase, is a critical stage within interphase of the cell cycle. During this phase, the cell meticulously replicates its entire genome, ensuring that each chromosome is duplicated. This DNA replication is essential to produce two identical sister chromatids, preparing the cell for subsequent division into two daughter cells.
Question 5: Which organelle is responsible for packaging and modifying proteins for transport?
- Golgi apparatus (Correct answer)
- Endoplasmic reticulum
- Lysosome
- Cytoplasm
Correct answer: Golgi apparatus
The Golgi apparatus, also known as the Golgi complex or Golgi body, plays a central role in the endomembrane system. It receives proteins and lipids from the endoplasmic reticulum, further modifies them, sorts them, and then packages them into vesicles. These vesicles are then transported to their final destinations, either within the cell or for secretion outside the cell.
Which of the following structures is responsible for energy production in eukaryotic cells?