Cell Biology Quiz-13

Cell Biology Quiz-13

Dear Readers,

NEET is the most famous and important medical entrance examination held in our country. This exam is an objective type, an offline test which includes 4 sections namely– Physics, Chemistry, Botany, and Zoology. The maximum marks that can be scored are 720 marks and have 180 questions. About half of the paper consists of questions from Biology, as the NEET exam essentially focuses on capacitating students to go for seats in medical courses. One of the most significant and crucial sections in the NEET exam is of Biology. It comprises of theories, descriptions, discoveries, diagrams, definitions, explanations of differences, and relations. The majority of the topics covered in the NEET syllabus are from the NCERT syllabus of Class 11 & 12 and other related sources become part of the rest of the syllabus. Clear Exam curates a list of articles selected by professionals who recommend the highly vital topics for NEET exams. The table below takes you directly to the respective topic where the in-depth article and the MCQs are available for an easy and productive learning experience. Prior to solving NEET question papers or practicing mock tests, you must ensure to study the basic concepts in NEET and practice a few sample questions related to this exam. Students will be covered for all their studies as the topics are available from basics to even the most advanced. .

Q1.   During the replication of DNA, the synthesis of DNA on lagging strand takes place in segments. These segments are called

•  Double helix segments
•  Satellite segments
•  Kornberg segments
•  Okazaki segments

Solution
(d) During DNA replication, there occur a simultaneous continuous synthesis of DNA at both the strands of template in 5’ →3’ direction of newly synthesised strand. Okazaki et.al, (1968) suggested that it is only one strand, which shows such a continuous replication (called leading strand), while other strand replicates in a discontinuous manner, i.e., synthesises short fragments called Okazaki fragments. This discontinuous strand is called lagging strand.

Q2.   Which of the following feature is common to prokaryotes and many eukaryotes?

•  Cell wall is present
•  Chromosomes are present
•  Sub-cellular organelles are present
•  Nuclear membrane is present

Solution
(a) In prokaryotes, cell wall is present and possesses muramic acid. Membrane bound organelles are absent

Q3.   Acrosome is formed by

•  Mitochondria
•  Golgi body
•  Ribosomes
•  Lysosome

Solution
(b) During maturation of sperm, the acrosome is formed by the Golgi apparatus.

Q4.   Prokaryotic cells are generally….. and multiply more rapidly than the eukaryotic cells

•  Large
•  Small
•  Convex
•  Biconcave

Solution
(b) Prokaryotic cells are generally smaller and multiply more rapidly than the eukaryotic cells

Q5.   Number of carbons in ring of deoxyribose sugar is

•  Four
•  Five
•  Six
•  Three

Solution
  (b) Monosaccharides area simplest sugars and can be triose, tetrose, pentose, hexose, heptose, heptose for 3, 4, 5, 6 and 7 C-atom containing sugar respectively. Triose: Glyceraldehyde, dihydroxyacetone Tetrose: Erythrose, threose Pentose: Ribose, deoxyribose, ribulose Hexose: Glucose, fructose, mannose, galactose

Q6.   Fat storing granules are

•  Elaioplast
•  Amyloplast
•  Aleuroplast
•  None of these

Solution
(a) Leucoplasts are of three types: (i) Elaiopasts which store facts (ii) Amyloplasts which store carbohydrates (iii) Aleuroplasts which store proteins.

Q7.   Which of the following four cell structures is correctly matched with the accompanying description?

•  Plasma membrane – Lipid bilayer, in which proteins are embedded
•  Mitochondria – Bacteria like elements with inner membrane highly folded
•  Chloroplasts – Bacteria like elements with inner membrane forming sacs containing chlorophyll, found in plant cells and algae
•  Golgi apparatus – Stacks of flattened vesicles

Solution
(d) Plasma membrane – Lipid bilayer, in which proteins are embedded Mitochondria – Bacteria like elements with inner membrane highly folded Chloroplasts – Bacteria like elements with inner membrane forming sacs containing chlorophyll, found in plant cell and algae. Golgi apparatus – Stacks of flattened vesicles

Q8.   Identify A to D in the diagrammatic representation of internal structure of centrioles

•  A-Interdoublet bridge, B-Central microtubule, C-Plasma membrane, D-Radial spoke
•  A-Plasma membrane, B-Central microtubule, C-Interdoublet bridge, D-Radial spoke
•  A-Plasma membrane, B-Interdoublet bridge, C-Central microtubule, D-Radial spoke
•  A-Plasma membrane, B-Interdoublet bridge, C-Radial spoke, D-Central microtubule

Solution
(c) A-Plasma membrane, B-Interdoublet bridge, C-Central microtubule and D-Radial spoke

Q9.   Middle lamella is present

•  Inside the secondary wall
•  Inside the primary wall
•  Outside the primary wall
•  In between secondary and tertiary walls

Solution
(c) Middle lamella is a thin binding layer between the cell wall of adjacent plant cells. It is chemically formed of pectates of calcium and magnesium. It is present towards outside of primary wall.

Q10.   Glycocalyx is associated with

•  Nucleolus
•  Plasma membrane
•  Nucleus
•  Nucleosome

Solution
(b) Bacterial cells have a chemically complex cell envelope. The cell envelope consists of a tightly bound three-layered structure, ie., the outermost glycocalyx followed by the cell wall and then the plasma membrane. The glycocalyx is made up of sugar and proteins.