CLEP Biology Cell Organelle Structure/Function 2 — Questions and Answers
Question 1: Which organelle is responsible for modifying, sorting, and packaging proteins for secretion or delivery to other organelles?
- Smooth endoplasmic reticulum
- Golgi apparatus (Correct answer)
- Lysosome
- Peroxisome
Correct answer: Golgi apparatus
The Golgi apparatus receives proteins from the ER and modifies, sorts, and packages them into vesicles for their final destinations.
Question 2: Cilia and flagella in eukaryotic cells are constructed primarily from which protein arrangement?
- Actin filaments in a 9+2 pattern
- Microtubules in a 9+2 arrangement (Correct answer)
- Intermediate filaments in a 9+0 pattern
- Microfilaments in a 7+2 arrangement
Correct answer: Microtubules in a 9+2 arrangement
Eukaryotic cilia and flagella contain an axoneme composed of nine peripheral microtubule doublets surrounding two central microtubules (9+2 arrangement).
Question 3: Which component of the endomembrane system is most directly involved in lipid synthesis?
- Rough endoplasmic reticulum
- Smooth endoplasmic reticulum (Correct answer)
- Nuclear envelope
- Golgi cis face
Correct answer: Smooth endoplasmic reticulum
The smooth ER lacks ribosomes and is specialized for lipid synthesis, including phospholipids and steroids.
Question 4: What is the primary function of the nucleolus found within the nucleus?
- DNA replication
- Ribosomal RNA synthesis and ribosome assembly (Correct answer)
- mRNA processing and splicing
- Nuclear pore formation
Correct answer: Ribosomal RNA synthesis and ribosome assembly
The nucleolus is the site of rRNA transcription and the assembly of ribosomal subunits before their export to the cytoplasm.
Question 5: Peroxisomes carry out oxidative reactions that produce hydrogen peroxide; they prevent cell damage by containing which enzyme?
- Lipase
- Catalase (Correct answer)
- Protease
- Amylase
Correct answer: Catalase
Catalase in peroxisomes rapidly breaks down hydrogen peroxide into water and oxygen, neutralizing this toxic byproduct.
Question 6: In plant cells, the central vacuole serves multiple roles. Which of the following is NOT a function of the central vacuole?
- Maintaining turgor pressure
- Storing pigments and waste products
- Synthesizing chlorophyll (Correct answer)
- Isolating harmful materials
Correct answer: Synthesizing chlorophyll
Chlorophyll synthesis occurs in chloroplasts, not in the central vacuole, which functions in storage, turgor regulation, and waste isolation.
Question 7: Which cytoskeletal element is most responsible for maintaining cell shape and anchoring organelles in animal cells?
- Microfilaments (actin)
- Intermediate filaments (Correct answer)
- Microtubules
- Spectrin networks
Correct answer: Intermediate filaments
Intermediate filaments are the most stable cytoskeletal components and play a primary role in maintaining cell shape and anchoring organelles like the nucleus.
CLEP Biology Cell Organelle Structure/Function 2
Which organelle is responsible for modifying, sorting, and packaging proteins for secretion or delivery to other organelles?