1st year biology Chapter 4 The Cell Question an Answers
Short and Simple Question an Answer
Q1: What is nucleoid?
Ans: In prokaryotic cell nucleic material is usually coiled and concentrated in a region of the cell is called nucleoid.
Q2: What is active transport?
Ans: It is the process in which movement of molecules from lower concentration to the higher concentration by energy.
Q3: What is pinocytosis?
Ans: It is the process of taking fluid in large amount. When the living cells take up fluid vesicles and it is also called as cell drinking.
Q4: What is meant by nucleoplasm?
Ans: The nucleus is filled with protein rich substances called nucleoplasm.
Q5: Define chromatides?
Ans: Each chromosome consists of two threads like structures called chromatides.
Q6: What is cytosol?
Ans: Cytoplasm consists of a fluid matrix called cytosol in which the organells are found.
Q7: What is fluid mosaic model of DNA?
Ans: Singer and Nicholson proposed working model of plasma membrane called fluid mosaic model.
Q8: What are the main functions of cell membrane?
Ans: The main functions of plasma membrane are protection of protoplasm, regulation of flow of solutes and material across it due to its selective permeability.
Q9: Define vacules?
Ans: Vacules are non protoplasmic liquid filled cavities surrounded by tonoplast.
Q10: How many membrane? components are of plasma?
Ans: There arc two components of plasma membrane, phospholipids and protein.
Q11: What is cyclosis?
Ans: Cytoplam shows a movement in circular manner called cyclosis.
Q12: What is cytoskeleton?
Ans: The network of fibrous proteins give three dimensional structure to cell called cytoskeleton.
Q13: Define microfilaments?
Ans: Cytoplasm consists of a mass of tiny filaments are called microfilaments.
Q14: Define osmosis?
Ans: Movement of solvent molecules from the region higher concentration to the region of lower concentration in the presence of a semi permeable membrane is called osmosis.
Q15: What is chromatin network?
Ans: A network of fine loosely connected threads in the nucleoplasm is called chromatin network.
Q16: What is fractionation?
Ans: It is the isolation of cellular component by breaking and spinning the cell.
Q17: What are proplastides?
Ans: Proplastides are colorless. immature plastids found in meristematic tissues, where division of cells takes place.
Q18: What is the function of microtubules?
Ans: Microtubules help in the storage of cellulose, movement of chromosomes during cell division, movement of organelles within cytoplasm and movement of cilia and flagella.
Q19: What are plastids?
Ans: Plastids are found in plant cells as a chemical synthesizers and storage bodies.
Q20: What is the function of microfilaments?
Ans: They help in the internal motion of Cells.
Q21: Why cell membrane referred as selective permeable membrane membrane? or differential permeable
Ans: Cell membrane referred as selective permeable membrane or differential permeable membrane because it offers a barrier between the cell contents and their environment; allow only selective substances to pass through it.
Q22: Why phagocytosis referred as cell eating process?
Ans: Because plasma membrane absorbs solid particles in this process.
Q23: Why mitochondria are known as power house of the cell?
Ans: Mitochondria are known as power house of the cell because they are the main centers of the intercellular energy production.
Q24: Why ribosomes are called as protein factories?
Ans: Ribosomes are called as protein factories because they are composed of RNA and protein and they take part in the protein synthesis.
Q25: Why nucleus is considered as a brain of cell?
Ans: Nucleus is considered as a brain of a cell because it controls all the vital activities of a cell.
Q26: What will happen if the function of lysosomes would disturb in cell?
Ans: It may cause the abnormal conditions or diseases.
Q27: Why did it take nearly 200 years from the time of Robert Hooke for the cell theory to develop?
Ans: Because scientists had to technology to develop. wait for the
Q28: Say for instance you are looking a single cell that is green in colour. How do you it is a plant cell?
Ans: Animal cells do not have the chloroplast which makes plant cells look green, so it is a plant cell.
Q29: Which organelle act as a lysosome in plant cell and why?
And: Vacules sometime act as a lysosome in plant cell because they contain hydrolytic enzyme and after the death of cell the enzymes of vacule cause the break down of cell.
Q30: How prokaryotes are different from eukaryotes?
Ans: Prokaryotes are distinguished from eukaryotes on the basis of nuclear organization specifically they lack nuclear membrane and they also lack any intracellular organelle which is double membranacious.
Q31: What will happen if chromosome loses its centromere?
Ans: It will be unable to pair with any other chromosome and will result the cell death.
Q32: Why lysosomes are referred as suicide sacs?
Ans: Lysosomes contain power digestive enzymes and they have capacity of total cell destruction because of this they are referred as suicide sacs.
Q33: What would happen to a plant cell that suddenly lost its chloroplast?
Ans: If the chloroplast die or disappear then the plant would die of hunger.
Q34: Why organelles are important in cells?
Ans: Organelles are important in cells because without organelles a cell would not be able to anything and it would be dead.
Q35: How rough endoplasmic reticulum is differs from smooth endoplasmic reticulum?
Ans: Rough endoplasmic reticulum contains ribosomes on their outer surface while smooth endoplasmic reticulum does not contain ribosomes on their surface..
Q36: Which organelle of a cell is transferred from mother only to new generation? and why?
Ans: Mitochondria are transferred from mother to new generation because these are present only in eggs not in sperms.
Q37: Which organelles of a cell have its own DNA except nucleus?
Ans: Mitochondria and plastids have their own DNA.
