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The correct option is (a) True

To elaborate: The cell MEMBRANE is a phospholipid bilayer. The cell membrane has two TYPES of PROTEINS- peripheral proteins and integral proteins. Peripheral proteins are present on the surface of the membrane.

Correct CHOICE is (b) They are BOUND by a single membrane

To elaborate: Inclusion bodies are not covered by membranes and lie freely in the cytoplasm. They STORE reserve material such as PHOSPHATE granules. blue-green BACTERIA contain gas vacuoles which is an inclusion body.

Right option is (d) CELL membrane

To explain I would SAY: Mesosome is a characteristic feature of prokaryotes, which is not PRESENT in eukaryotic cells. It is a DIFFERENTIATED form of cell membrane derived by the INFOLDINGS of the cell membrane in prokaryotes.

The correct OPTION is (d) MIDDLE lamella separates cells and is COMPOSED of sodium acetate

Easy explanation: The cell wall is made of THREE main layers, namely, PRIMARY cell wall, secondary cell wall and middle lamella. Cell wall of a young plant is made of primary cell which composes a loose network of cellulose microfibrils. Secondary cell wall forms as the cell matures and composes cellulose and lignin. Middle lamella separates cells and is composed of calcium pectate.

The correct option is (B) All CELLS contain a nucleus which has the genetic material

For explanation I would say: MATTHIAS Schleiden and Theodore Schwann together formulated the CELL theory. It states that living things are composed cells, that the cell is the BASIC unit of life, and that new cells arise from existing cells.

Right choice is (c) Peroxisomes

For explanation: The functions of the endoplasmic reticulum (ER), Golgi bodies, VACUOLES and lysosomes are coordinated. Hence, they form an ENDOMEMBRANE system. Peroxisomes are not a part of the endomembrane system.

The correct option is (a) ATP

To explain I WOULD say: Energy for the TRANSPORT of particles through active mode is derived from ATP. In active mode of TRANSPORTATION, the transport of particle takes place against the concentration gradient. Therefore, active transport REQUIRES energy to transport particles.

Right answer is (d) Mitochondria can’t synthesize their own proteins and depend on rough endoplasmic reticulum

Explanation: Mitochondrion is a rod-shaped organelle bounded by two MEMBRANES and is also called as the power house of the cell. Mitochondrion has an outer membrane, an INNER membrane, CRISTAE and MATRIX. The inner membrane of the mitochondria is highly folded and these folds provide greater SURFACE area for the generation of ATP molecules. Mitochondria can synthesize their own proteins since they have ribosomes and genetic material in them.

The correct option is (a) They are BOUND by a single membrane

The BEST explanation: RIBOSOMES are not bound by a membrane. They are made of RNA and proteins. Ribosomes were first observed by George Palade. The small subunit of the PROKARYOTIC RIBOSOME is 30S.

Right answer is (c) Polar molecules

Explanation: Since the CELL MEMBRANE is a phospholipid bilayer having NON – polar lipid tail groups, polar molecules cannot PASS through the membrane without the assistance of carrier proteins present within the membrane.

The correct choice is (C) osmosis

For explanation: The cell MEMBRANE is a PHOSPHOLIPID bilayer which is semi – permeable. Water MOVES across this membrane by the process of diffusion. The diffusion of water across a semi – permeable membrane is KNOWN as osmosis.

Correct option is (d) Pleuro Pneumonia Like Organisms

Explanation: The full form of PPLO is Pleuro Pneumonia Like Organisms. They are a type of prokaryotic organisms, which ALSO include bacteria, blue – green ALGAE and MYCOPLASMA. The lack a true NUCLEUS.

Correct option is (a) Centromere

For explanation I would say: Every visible CHROMOSOME has two sister chromatids which are CONSTRICTED together at a point known as the centromere.During MITOSIS, the spindle fibres attach to the CHROMOSOMES via the centromere.

Correct option is (c) Stroma

To EXPLAIN I WOULD say: Chloroplasts are plastids which contain the GREEN pigment chlorophyll. The stroma is the GROUND substance of the chloroplast. It contains enzymes which are REQUIRED for the synthesis of carbohydrates and proteins.

Right option is (b) LYSOSOMES

The explanation: The ENDOPLASMIC reticulum (ER), Golgi bodies, VACUOLES and lysosomes form the endomembrane system. Organelles such as mitochondria, chloroplasts and peroxisomes are not a PART of the endomembrane system.

The CORRECT option is (a) 10 – 20 μm

The best explanation: The size of a typical eukaryotic cell is 10 – 20 μm. PROKARYOTIC cells are generally smaller than eukaryotic cells and also multiply more RAPIDLY. Bacteria, blue-green ALGAE, mycoplasma and PPLO (Pleuro PNEUMONIA Like Organisms) are the types of prokaryotic cells.

Correct option is (a) True

Best explanation: Matthias Schleiden, a German botanist and Theodore Schwann, a British zoologist together formulated the cell theory. It states that LIVING THINGS are composed CELLS, that the cell is the basic unit of life, and that NEW cells arise from EXISTING cells.

The CORRECT answer is (d) MATTHIAS SCHLEIDEN

Easy explanation: Matthias Schleiden was a German botanist who observed the different types of cells present in plant tissue of various types of plants in 1838. Schleiden and Schwann together FORMULATED the cell THEORY.

The correct option is (B) False

Easiest explanation: Chromosomes FORM when chromatids condense during reproduction. Centromeres are the primary constrictions of chromosomes. Based on the position of centromeres, chromosomes can be CLASSIFIED into acrocentric, metacentric, sub-metacentric and telocentric chromosomes.

Right choice is (b) Mitochondria

For explanation I would say: Endomembrane SYSTEM COMPRISES of vacuoles, endoplasmic reticulum, endosomes, nuclear membrane, vesicles, lysosomes and PLASMA membrane. They act as a SINGLE FUNCTIONAL and developing unit of the cell.

Correct answer is (c) Smooth ENDOPLASMIC reticulum has ribosomes attached to their surface and ACTS as site of protein synthesis

Easiest EXPLANATION: Endoplasmic reticulum is a complex NETWORK of membrane bounded TUBULES. They are classified as smooth and rough endoplasmic reticulum. Rough endoplasmic reticulum has ribosomes attached to their surface and acts as site of protein synthesis. Rough endoplasmic reticulum is connected by nuclear membrane at one end and Golgi apparatus on the other end.

Right choice is (d) The model FAILS to explain the cell growth and cell division

To ELABORATE: Plasma membrane was coined by Singer and Nicholson to be a fluid mosaic model.According to this model, the proteins are DISPERSED randomly on the surface and the INTERIOR of the plasma membrane. The word fluid in this model refers to the fluid flexible nature of the plasma membrane. The model EXPLAINS the cell growth and cell division.

Right choice is (d) Metacentric chromosome

Explanation: BASED on the position of the CENTROMERE, the chromosomes can be classified into FOUR TYPES. The metacentric chromosome has its centromere in the middle, thus forming two EQUAL arms of the chromosome.

Correct option is (b) Osmoregulation of the cell

Easy explanation: Vacuoles CONTAIN substances for storage such as water, or excretory PRODUCTS such as sap and other materials not useful for the cell. the CONTRACTILE vacuole in Amoeba is RESPONSIBLE for osmoregulation and excretion.

The correct choice is (a) PECTIN

For explanation I WOULD say: The algal cell wall contains cellulose, galactans, mannans and minerals like calcium CARBONATE. However, it does not contain pectin. The plant cell wall contains cellulose, hemicellulose, PECTINS and proteins.

Correct choice is (C) On the surface

The best I can explain: Endoplasmic reticulum is of TWO TYPES- SMOOTH endoplasmic reticulum and rough endoplasmic reticulum. The rough endoplasmic reticulum has ribosomes present on its outer surface.

Correct choice is (d) ABILITY to move within the membrane

Easiest explanation: FLUIDITY of the cell membrane is the measure of the ability to move within the membrane. This movement is ALLOWED DUE to the quasi-fluid nature of LIPID present in the cell membrane.

Right choice is (C) Singer and NICHOLSON

Easy explanation: Singer and Nicholson proposed the fluid MOSAIC model of the CELL membrane in 1972. According to this model, the lateral movement of proteins was enabled by the quasi-fluid NATURE of lipid.

The correct ANSWER is (d) 40%

For explanation: The cell membrane is a phospholipid BILAYER. It also contains VARIOUS proteins. The protein and lipid percentages vary in different cells. Human ERYTHROCYTE membranes are made of 40% LIPIDS.

The correct option is (C) The HYDROPHILIC tails face outwards

To elaborate: The cell MEMBRANE is a phospholipid BILAYER in which the polar and hydrophilic phosphate HEAD groups face outwards, while the non-polar and hydrophilic lipid tails face each other.

Right choice is (d) Monerans

The best I can explain: EUKARYOTIC cells possess a true NUCLEUS. Plants, fungi and PROTISTS are eukaryotic ORGANISMS as they have a well – defined nucleus. However, monerans do not possess a well – defined nucleus and are THUS, prokaryotes.

Correct option is (c) Rough ENDOPLASMIC reticulum

To ELABORATE: The rough endoplasmic reticulum CONTAINS ribosomes on its surface. Hence, the rough endoplasmic reticulum is ACTIVELY involved in PROTEIN synthesis. Smooth endoplasmic reticulum is involved in lipid synthesis.

Correct answer is (a) CELLULOSE

To explain I would say: The algal cell WALL CONTAINS cellulose, galactans, mannans and minerals LIKE calcium carbonate. The plant cell wall contains cellulose, hemicellulose, PECTINS and proteins. Hence, cellulose is the common component.

The correct answer is (a) CYTOSOL

The best explanation: The FLUID INSIDE the cell enclosed by plasma membrane. It is LITTLE viscous and comprises of 80% water. CYTOPLASM without cell organelles is termed as Cytosol. Cytosol is not static and movement of cytoplasm is termed as cyclosis

Right choice is (d) Nucleolus contains RNA, DNA, HISTONE and non-histone proteins

To ELABORATE: Nuclear membrane is a double layered covering of nucleus which is separated by a perinuclear space. Nuclear pores allow the transfer of materials and disrupt the continuity of nuclear membrane. NUCLEOPLASM is also termed as “Karyolymph” and act as SITE for SYNTHESIS of DNA and RNA. Chromatin contains RNA, DNA, histone and non – histone proteins.

The correct option is (c) NUCLEOPLASM condenses and group together to form chromosomes

Easiest EXPLANATION: In PLANT cells, nucleus lies towards the periphery due to the large nucleus that occupies almost the entire region of the cell. Nucleus helps in reproduction and acts as the control centre of the cell. Chromatin condenses and group together to form chromosomes. Nucleus COMPRISES of NUCLEAR membrane, nuclear pores, nucleolus, nucleoplasm and chromatin.

Correct choice is (B) Microtubules are COMPOSED of protein actin and microtubules are composed of protein tubulin

For explanation I would say: Cytoskeleton is the NETWORK of minute proteinaceous STRUCTURE in the CYTOPLASM and which mainly contains microfilaments and micro tubules. Microtubules are composed of protein tubulin and microtubules are composed of protein actin.

Correct CHOICE is (a) True

Easy explanation: Active TRANSPORT REQUIRES energy to transport particles from LOWER concentration to higher concentration. In passive transport, cell doesn’t EXPEND any energy to transport particles across cells.

Right choice is (c) Virchow introduced the CONCEPT that genetic material is present inside the nucleus

Explanation: Robert Hooke discovered cell in 1665. Robert brown made the most major contribution to the history of cell by DISCOVERING nucleus. Cell theory was developed by Schleiden and SCHWANN. Virchow STATED that the NEW cells arise from the pre-existing cells.

The correct answer is (c) Aleuroplasts

To elaborate: CHROMOPLASTS impart colours to the different cells of a plant such as yellow colour of a flower or a FRUIT. Elaioplasts STORE oils and FATS, amyloplasts store starch and aleuroplasts store proteins.

Correct CHOICE is (c) Kinases

To ELABORATE: The lysosome contains VARIOUS enzymes collectively known as LYSOSOMAL acid hydrolases. The enzymes are hydrolytic enzymes such as lipase, protease and carbohydrase. Kinases are not hydrolytic enzymes.

Right option is (a) PEROXISOMES

Easiest EXPLANATION: The functions of the ENDOPLASMIC reticulum (ER), GOLGI bodies, vacuoles and lysosomes are coordinated. Hence, they form an endomembrane system. Peroxisomes are not a part of the endomembrane system.

Right choice is (c) The secondary wall accelerates the GROWTH of the CELL wall

The best explanation: The cell wall of a young plant cell can grow because of the growth of the PRIMARY wall of the cell wall. However, as the plant gets bigger, the secondary wall which is FORMED towards the cell membrane diminishes this growth.

The CORRECT choice is (b) Molecules are transported along their CONCENTRATION gradient

For explanation: Active TRANSPORT is the movement of molecules or IONS from a region of their lower concentration to a region of their higher concentration, against the concentration gradient. It requires energy in the form of ATP.

Correct OPTION is (d) All cells ARISE from pre-existing cells

Best explanation: Omnis CELLULA-e cellula, means that each cell is derived from a pre-existing cell by cell division. It is the CULMINATION of a profound insight of the late 19th century and STATED by the German pathologist Rudolf Virchow.

Right answer is (d) In acrocentric chromosomes, CENTROMERE is present in the end of the chromatids

Easiest explanation: Chromosomes are rod SHAPED structures that condenses together when the cell is about divide. Chromosomes are COMPOSED of DNA, RNA and proteins which act as repository for inheritance. Kinetochores are disc like structures that are present on the sides of centromeres. In telocentric chromosomes, centromere is present in the end of the chromatids.