Consider statements about the cytoskeleton: 1. Microtubules are made of tubulin. 2. Microfilaments are made of actin. 3. Intermediate filaments are made of cellulose. Which are correct? MCQ with Answer and Explanation
Consider statements about the cytoskeleton: 1. Microtubules are made of tubulin. 2. Microfilaments are made of actin. 3. Intermediate filaments are made of cellulose. Which are correct?
A. 1 and 2 only
B. 1 and 3 only
C. 2 and 3 only
D. 1, 2 and 3
Answer: Option A
Solution (By JKExamLibrary)
The cytoskeleton provides structural support and is composed of three main types of filaments. Microtubules are hollow tubes made of the protein tubulin. Microfilaments are solid rods composed of actin. Intermediate filaments are made of various fibrous proteins like keratin, not cellulose, which is a plant cell wall component. Thus, statements 1 and 2 are correct.
Explanation:
Iodine is a key constituent of the thyroid hormones thyroxine (Tâ) and triiodothyronine (Tâ). Deficiency leads to goiter and hypothyroidism. Iron is for hemoglobin, calcium for bones, zinc for enzyme function. Iodized salt is a public health measure to ensure adequate iodine intake.
Explanation:
Simple columnar epithelium lines the stomach, intestines, and gallbladder, and functions in secretion and absorption. It often has microvilli (brush border) or goblet cells. Squamous epithelium lines alveoli and blood vessels, cuboidal kidney tubules.
Explanation:
Fucoxanthin is a carotenoid pigment found in brown algae (Phaeophyceae) that gives them their characteristic brown or olive-green color, masking the green chlorophyll. Phycoerythrin is red (red algae), phycocyanin blue (cyanobacteria, some red algae). Brown algae include kelps and Fucus.
No comments yet. Be the first to start the discussion!