Cells

Question 1

What is the function and characteristics of the cell surface membrane?

Answer 1

1. Made of lipids and proteins.
2. It is partially permeable.
3. It controls the substances entering or leaving the cell.

Question 2

What is the function and characteristics of the nucleus?

Answer 2

1. The nucleus consists of a small round denser protoplasm called nucleoplasm which is surrounded by a nuclear envelope.
2. It contains chromatin.
3. It is made up of Deoxyribonucleic acid(DNA) which carries hereditary information.

Question 3

What is the function and characteristics of the cell wall?

Answer 3

1. The cell wall is only present in plant cells.
2. Cell wall is made of cellulose.
3. It protects the cell from injuries and gives the cell a regular shape.
4. It is also fully permeable.

Question 4

What is the function and characteristics of the Rough Endoplasmic Reticulum(RER)?

Answer 4

1. The RER appears rough because ribosomes are attached to it.
2. Ribosomes are required to make proteins
3. The RER transports protein to the Golgi apparatus for secretion out of the cell.

Question 5

What is the function and characteristics of the Smooth Endoplasmic Reticulum(SER)?

Answer 5

1. The SER does not have ribosomes.
2. It synthesizes substances such as fats and steroids .
3. It is involved in detoxification

Question 6

What is the function and characteristics of the Golgi apparatus?

Answer 6

1. It contains flattened spaces surrounded by membranes.

2. The Golgi apparatus packages the substances in vesicles for secretion out of the cell.

Question 7

What is the function and characteristics of the Mitochondria?

Answer 7

Mitochondria performs aerobic respiration. They oxidize food to release energy.

Question 8

What is the function and characteristics of the Chloroplasts?

Answer 8

Oval structures containing chlorophyll which is required for photosynthesis to occur.

Question 9

What is the function and characteristics of the Vacuoles?

Answer 9

1. Vacuoles stores substances within the cell
2. Animal cells have many vacuoles containing water and food substances.
3. Plant cells have a large central vacuole containing cell sap.

Question 10

What is the function and characteristics of the Red blood cells?

Answer 10

1. Haemoglobin in the cytoplasm of the red blood cell transports oxygen from lungs to all parts of the body.
2. It has no nucleus, thus enabling to carry more oxygen
3. It has a biconcave shape→ increasing the surface area to volume ratio➝ increases the rate of diffusion of oxygen into and out of the cell

Question 11

What is the function and characteristics of the Xylem tissue?

Answer 11

1. Xylem vessels are long hollow tube
2. They do not have cross walls to obstruct water flow through the lumen
3. Their walls are lignin to prevent vessels from collapsing

Question 12

What is the function and characteristics of the Root hair cell?

Answer 12

1. They absorb water from soil

2. They are long and narrow➝ increase the surface area to volume ratio