Organelles

Question 1

Name all of the organelles bound by a double membrane.

Answer 1

Nucleus (nuclear membrane), nucleolus, chloroplast, mitochondria.

Question 2

Name all of the organelles bound by a single membrane.

Answer 2

Smooth endoplasmic reticulum, rough endoplasmic reticulum, golgi (apparatus/body), vacuole, lysosome.

Question 3

What is the nuclear envelope?

Answer 3

The plasma membrane around the outside of the nucleus.

Question 4

What are the nuclear pores and their function?

Answer 4

Holes within the nuclear membrane which allow substances in and out of the nucleus, e.g mRNA.

Question 5

What is the nucleoplasm?

Answer 5

Granular, jelly-like material in the nucleus (like cytoplasm).

Question 6

What are chromosomes?

Answer 6

Linear DNA wrapped around proteins .

Question 7

What is the nucleolus and its function?

Answer 7

A sphere responsible for making rRNA and ribosomes.

Question 8

What is the function of the nucleus?

Answer 8

Holds the genetic information for each cell and is the site of DNA replication and transcription (making mRNA).

Question 9

What is the smooth endoplasmic reticulum and its function?

Answer 9

Made up of folded membranes called cisternae. Where the synthesis and transport of lipids and carbohydrates occurs.

Question 10

What is the rough endoplasmic reticulum and its function?

Answer 10

Made up of folded membranes called cisternae and covered in ribosomes, often wrapped around the nucleus. Where the production of proteins occurs.

Question 11

What is the golgi and its function?

Answer 11

Made up of folded membranes making fattened sacs called cisternae. Modifies proteins by adding carbohydrates to make glycoproteins. Uses vesicles to package and transport substances. Modify and transport lipids and transport carbohydrates.

Question 12

What is the mitochondria and its function?

Answer 12

On the inner membrane there are folds called cristernae. Remaining matrix is called stroma and is where enzymes and DNA are contained. Releases energy and produces ATP.

Question 13

What are ribosomes and their function?

Answer 13

Made up of two sub-units of rRNA and protein that come together during transcription. They create proteins. 70S are smaller and found in prokaryotes, 80S are bigger and found in eukaryotes.

Question 14

What are the lysosomes and their function?

Answer 14

Contain hydrolytic enzymes (lysozyme) that hydrolyse worn out organelles and pathogens.

Question 15

What is exocytosis?

Answer 15

The release of substances to the outside of the cell by golgi vesicles.

Question 16

What is the chloroplast and its function?

Answer 16

Has stacks of thylakoids called grana which have chlorophyll in. Remaining matrix is called the stroma which contains enzymes for photosynthesis and DNA.

Question 17

What is the vacuole and its function?

Answer 17

Single membrane called the tonoplast. Gives the cell stability by keeping it turgid and stores sugars and amino acids.

Question 18

What is the cell wall and its function?

Answer 18

Required for stability and resisting osmotic changes so that no shrinkage or lysis occurs. Made out of cellulose in plant and algae, chitin in fungi, murein in prokaryotes.

Question 19

What are the organelles that every prokaryote has?

Answer 19

Plasma membrane, circular DNA, cytoplasm, ribosomes, cell wall.

Question 20

What is the purpose of a flagellum?

Answer 20

For locomotion

Question 21

What is the purpose the pilli?

Answer 21

For attachment to other cells or surfaces, usually in sexual reproduction

Question 22

What is the purpose of the capsule?

Answer 22

For additional protection

Question 23

What are the plasmids?

Answer 23

Small circles of DNA.