GCSE Cells topics

Question 1

What is a nucleus

Answer 1

The nucleus controls all the activities in the cell and is surrounded by the nuclear membrane. Also it contains the genes on the chromosomes that carry the instructions for making the proteins needed to build new cells or new organisms. The average diameter is around 10 micrometers.

Question 2

What is cytoplasm

Answer 2

It is a liquid gel which the organelles are suspended and where most of the chemical reactions needed for life take place.

Question 3

What is the cell membrane

Answer 3

It controls the passage of substances such as glucose and mineral ions into the cell. It also controls the movement of substances such as urea or hormones out of the cell.

Question 4

What is mitochondria

Answer 4

This is the structure in the cytoplasm which is where aerobic respiration takes place, releasing energy for the cell. They are very small: 1-2 micrometers in length and only 0.2-0.7 micrometers in diameter.

Question 5

What are ribosomes

Answer 5

This is where protein synthesis takes place, making all the proteins needed in the cell.

Question 6

What are chloroplasts

Answer 6

A chloroplast is a structure in a plant cell that contains large amounts of chlorophyll. Chloroplasts play a key role in the process of photosynthesis and convert light energy from the sun into chemical energy (carbohydrates) for the plant.

Question 7

What is a permanent vacuole

Answer 7

It is a space in the cytoplasm filled with cell sap and this is important for keeping the cells rigid to support the plant.