NCERT Class 9 Science Solutions: Chapter 5 –The Fundamental Unit Of Life Part 2

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Question 1:

Q. fill in the gaps in the following table illustrating differences between prokaryotic and eukaryotic cells.

Table of Illustrating Differences between Prokaryotic and Eukaryotic Cells for the Fundamental Unit of Life
Table of Illustrating Differences Between Prokaryotic and Eukaryotic Cells for The Fundamental Unit of Life

Prokaryotic cell

Eukaryotic cell

1.

Size: generally small 1

1.

Size: generally large

2.

Nuclear region: _________ and is known as___.

2.

Nuclear region: well-defined and surrounded by a nuclear membrane

3.

Chromosome: single

3.

More than one chromosome

4.

Membrane-bound cell organelles are absent.

4.

____________________________.

A.

Table Contant Shows Illustrating Differences between Prokaryotic and Eukaryotic Cells for the Fundamental Unit of Life
Table contant shows Illustrating Differences Between Prokaryotic and Eukaryotic Cells for The Fundamental Unit of Life

Prokaryotic cell

Eukaryotic cell

1.

Size: generally small 1

1.

Size: generally large

2.

Nuclear region: poorly defined because of the absence of a nuclear membrane, and is known as nucleoid.

2.

Nuclear region: well-defined and surrounded by a nuclear membrane

3.

Chromosome: single

3.

More than one chromosome

4.

Membrane-bound cell organelles are absent.

4.

Membrane-bound cell organelles such as mitochondria, plastids, etc., are present

Question 1:

Q. Can you name the two organelles we have studied that contain their own genetic material?

A. Mitochondriaandplastids are the two organelles that contain their own genetic material. Both these organelles have their own DNA and ribosomes.

Question 2:

Q. If the Organisation of a cell is destroyed due to some physical or chemical influence, what will happen?

A. Cell is the smallest unit of life, which is capable of all living functions. If the Organisation of a cell is destroyed due to some physical or chemical influence, then the ability of the cell to perform all living functions such as respiration, nutrition, excretion, etc. would be affected.

Question 3:

Q. why are lysosomes known as suicide bags?

Image of Lysosomes Known as Suicide Bags for The Fundamental …

Lysosomes Known as Suicide Bags for Cells

A. Lysosomes are membrane-bound vesicular structures that contain powerful digestive enzymes. These enzymes are capable of breaking down any foreign food particle or microbes entering the cell. Sometimes, lysosomes can cause self-destruction of a cell by releasing these digestive enzymes within the cells. Hence, they are also known as ‘suicidal bags’.

Question 4:

Q. where are proteins synthesized inside the cell?

A. Ribosomes are the site for protein synthesis. Ribosomes are very small structures found either in a free state, suspended in the cytoplasm, or attached to the surface of the endoplasmic reticulum. They are composed of ribonucleic acids and proteins.

Question 1:

Q. Make a comparison and write down ways in which plant cells are different from animal cells.

A.

Table of Different between Animal Cell and Plants Cell for the Fundamental Unit of Life
Table of Different between Animal Cell and Plants Cell for the Fundamental Unit of Life.

Animal cell

Plant cell

Animal cells are generally small in size.

Plants cells are usually larger than animal cells.

Cell wall is absent.

Cell wall is present.

Except the protozoan euglena, no animal cell possesses plastids.

Plastids (chromoplasts and leucoplasts) are present.

Vacuoles are smaller in size.

Vacuoles are larger in size,

Animal cells without cell wall

Aanimal Cel

Plant cell with cellwall

Plant Cell

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