Online MDcat Test Preparation Series Quiz-02

1.Hemoglobin consists of ____ polypeptide chains

1. 2
2. 4
3. 6
4. 8

Feedback: Hemoglobin consists of four polypeptide chains (two α and two β chains). Each of these chains is associated with a heme prosthetic group. Each hemoglobin chain has a molecular weight of 68 kDa. A hemoglobin molecule is made up of four polypeptide chains, two alpha chains of 141 amino acid residues each and two beta chains of 146 amino acid residues each.

2.Lysosomes contain variety of enzymes called

a. Pcroxygcnasc
b. Peroxidase
c. Hydrolases
d. lyases

3.The cisternae together with vesicles are called

a. Multi cisternae
b. Golgi complex
c. Cirovasicle
d. Non of these

4.Cell wall of cells are held together by

a. Primary wall
b. Secondary wall
c. Middle lamella
d. Non of these

5.The membrane is like sea of lipids in which proteins are floating

a. Unit membrane model
b. Fluid mosaic model
Cr Roberston model
d. Non of these

6.Protein extending in double layer of lipids completely are called

A Intrinsic
B Extrinsic
C Permeases
D Non of these

Feedback: Intrinsic membrane proteins are embedded in the lipid bilayer so that the polypeptides come in contact with the non-polar region of the bilayer. There are two major types of intrinsic proteins: those with most of their mass outside the cytoplasm (Type I) and those with most of their mass inside the cytoplasm (Type II).

7.RER synthesizes

1. Protein
2. Primary lysosome
3. Protein and primary lysosome
4. Lipids

Feedback: Ribosomes on RER, which give RER its rough appearance, specialize in the synthesis of proteins that possess a signal sequence that directs them specifically to the ER for processing. Proteins synthesized by the RER have specific final destinations, such as the cell membrane, cell exterior, or the ER itself.

8.Leucoplast are present in

1. Green parts of plants
2. Pigmented cells
3. Non pigmented cells
4. All of these

9.Primary lysosomes arc synthesized in RER and processed in

a. Peroxisome
b. Endoplasmic reticulum
c. Nucleus
d. Golgi apparatus

Feedback: Enzymes of the lysosomes are synthesized in the rough endoplasmic reticulum and exported to the Golgi apparatus upon recruitment by a complex composed of CLN6 and CLN8 proteins.

10. Ribosomes are synthesized in

1. Peroxisome
2. Endoplasmic reticulum
3. Nucleus
4. Nucleolus of nucleus

Feedback: Eukaryote ribosomes are produced and assembled in the nucleolus. Ribosomal proteins enter the nucleolus and combine with the four rRNA strands to create the two ribosomal subunits (one small and one large) that will make up the completed ribosome