Worksheet solutions for chapter: The Fundamental Unit of Life for class 9 are provided below.
(1) What will happen if put an animal cell in hypotonic solution?
Ans- In hypotonic solution, outside solution is less concentrated (or solute is high concentrated) than solution of inside cell. More water will come inside the cell than will leave. Therefore, animal cell will swell up.
(2)What is cell wall? What is the use of cell wall?
Ans- Cells are enclosed in a membrane and it is surrounded by a cell wall. Cell wall gives shapes and rigidity to these cells.
(3)What are the chromosomes?
Ans- The thread like structures of nucleus which carry genes (Functional segments of DNA) and can be seen only when cell divides are called chromosomes. Chromosomes are composed of DNA and protein.
(4) Why viruses do not show characteristics of life?
Ans- Viruses have no membranes. Therefore, do not show characteristics of life until they enter a living body and use its cell machinery to multiply.
(5)Which cell organelle is involved in the formation of lysosomes?
Ans- Golgi apparatus is involved in the formation of lysosomes.
(6)Why lysosomes are necessary for cell?
Ans- The functions of lysosomes are to keep cell clean by digesting any foreign material (Food or bacteria) as well as worn – out cell organelles. Lysosomes break the complex substances into simpler substances with the help of powerful enzymes that are filled in lysosomes. Therefore, lysosomes are necessary for cleaning the cell.
(7)Give uses of osmosis and diffusion in cell.
Uses of osmosis in animal or plant cell-
(a) Unicellular freshwater organisms gain water through osmosis.
(b) Plant cells received water from roots through osmosis.
Uses of diffusion in animal or plant cell-
(a) The cell can exchange water and gases through diffusion.
(b) Different molecules of nutrition transport nutrition by moving in and out of the cell through diffusion.
(8)Differentiate between the SER and RER.
|1.||These are smooth endoplasmic reticulum||These are rough endoplasmic reticulum|
|2.||No ribosomes are attached||Ribosomes are attached|
|3.||Helps in manufacturing of fats.||Helps in manufacturing of proteins|
|4.||Detoxifying many poisons and drugs.||Sent protein in various places of cell|
(9)How vacuoles are helpful for plants?
Ans-Vacuoles are full of water, amino acids, glucose and salt which are necessary for cell life in plant. Vacuoles provide turgidity and rigidity to the cell.
(10) Name the cell organelles and also tell whether they are found in animal or plant cell.
|SN||Name of the cell organelle||Plant cell||Animal cell|