Cell components

Question 1

What are the components of a nucleus?

Answer 1

Nuclear envelope
Nuclear pores
Chromatin 
Nucleolus
Nucleoplasm

Question 2

What is the function of a nucleus?

Answer 2

Controls mRNA and tRNA production and hence protein synthesis.

Keep the genetic material of the cell in the form of DNA and chromosomes

Make ribosomes

Question 3

What is the structure of a mitochondria?

Answer 3

They have a double membrane and the inner membrane is folded into Cristae
The inside is called the matrix

Question 4

What are cristae for?

Answer 4

To provide a large surface area for enzymes and proteins involved in respiration to attach onto.

Question 5

What does the matrix contain?

Answer 5

Ribosomes,lipids and DNA

Question 6

What is the DNA in mitochondria used

Answer 6

Controlling the production of its own proteins

Question 7

What are the functions of mitochondria?

Answer 7

Site of aerobic respiration

Synthesis of ATP

Question 8

Where are mitochondria found? And what cells have an abundance of them and why?

Answer 8

They are found in cells that have a high level of metabolic activity and require a lot of ATP.
E.g. Muscle cells and epithelial cells

Question 9

Name the 4 structures in a chloroplast?

Answer 9

Chloroplast envelope
The grana
Thylakoids membrane
The stroma

Question 10

How are chloroplasts adapted to their function?

Answer 10

The grana have a large surface area for the attachment of things.

Chloroplasts contain DNA and ribosomes so they can manufacture proteins needed for photosynthesis.

Question 11

What are the two types of endoplasmic reticulum?

Answer 11

SER AND RER

Question 12

What is the rough ER for?

Answer 12

It contains ribosomes and a large surface area for the synthesis of proteins and glycoproteins.

Provides a pathway for the transport of proteins.

Question 13

What is the smooth ER for?

Answer 13

It lacks ribosomes

It synthesises,stores and transports lipids
It synthesises,stores and transports carbohydrates.

Question 14

What type of cells have a large ER?

Answer 14

Cells that manufacture a large amount of carbohydrates,proteins and lipids . eg the liver

Question 15

What is the structure of the Golgi apparatus?

Answer 15

It’s made of flattened sacs of membranes called cisternae surrounded by vesicles

Question 16

What are the functions of the Golgi apparatus?

Answer 16

Golgi modifies the proteins made from the ER and adds carbohydrate components to them to form glycoproteins.

It produces secretory enzymes
Transports,modifies and stores lipids.
Forms lysosomes.

Question 17

What is exocytosis?

Answer 17

When a Golgi vesicle moves to the surface and fuses with the cell membrane releasing the content of it to the outside.

Question 18

Where is the Golgi apparatus well developed?

Answer 18

In secretory cells like the intestines.

Question 19

What are Lysosomes?

Answer 19

When Golgi vesicles contain enzymes that hydrolyse cell walls of bacteria. (Lysozyme)

Question 20

What is the function of a lysosome?

Answer 20

Hydrolyzes material ingested by phagocytes

Digest worn out organelles

Break down cells after they have died.

Question 21

What is the function of a ribosome?

Answer 21

Protein synthesis.

Question 22

How much of the dry mass of a cell are ribosomes?

Answer 22

25%

Question 23

What ribosomes are found in eukaryotes?

Answer 23

80S ribosomes

Question 24

What is the function of a cell wall?

Answer 24

To provide mechanical strength to prevent the cell bursting under pressure.

Question 25

What is the structure of a vacuole?

Answer 25

A fluid filled sac with a single membrane

Question 26

What is the function of a vacuole?

Answer 26

Supporting plant cells by making them turgid

Act as a temporary food store