3.2.1.1 Structure of eukaryotic cells

Question 1

What is the function of the cell-surface membrane?

Answer 1

Controls the movement of substances in and out of the cell. Also contains receptor molecules which allow it to repond to chemicals such as hormones.

Question 2

What is the structure of the nucleus in eukaryotic cells?

Answer 2

Contains chromosomes made of protein-bound, linear DNA and one or more nucleoli.

Question 3

What is the function of the nucleus?

Answer 3

Stores the genetic material (DNA) and controls the cell’s activities by regulating transcription.

Question 4

What is the structure of mitochondria?

Answer 4

Have a double membrane; the inner membrane is folded into cristae, and the matrix contains enzymes for respiration.

Question 5

What is the function of mitochondria?

Answer 5

Site of aerobic respiration and ATP production.

Question 6

What is the structure of chloroplasts (in plants and algae)?

Answer 6

Have a double membrane and contain thylakoids stacked into grana, surrounded by stroma containing enzymes.

Question 7

What is the function of chloroplasts?

Answer 7

Site of photosynthesis; the light-dependent reactions occur in the thylakoids and the light-independent reactions occur in the stroma.

Question 8

What is the structure of the Golgi apparatus?

Answer 8

A stack of fluid-filled, membrane-bound sacs with vesicles at the edges.

Question 9

What is the function of the Golgi apparatus?

Answer 9

Processes and packages proteins and lipids for secretion or delivery to other organelles.

also makes lysosomes.

Question 10

What is the function of Golgi vesicles?

Answer 10

Transport proteins and lipids from the Golgi apparatus to their destination.

Question 11

What is the structure of lysosomes?

Answer 11

Membrane-bound organelles containing hydrolytic enzymes. Type of golgi vesicle.

Question 12

What is the function of lysosomes?

Answer 12

Break down waste materials, old organelles, and pathogens.

Question 13

What is the structure of ribosomes?

Answer 13

Small organelles made of protein and RNA; not membrane-bound.

Question 14

What is the function of ribosomes?

Answer 14

Site of protein synthesis.

Question 15

What is the structure of the rough endoplasmic reticulum (RER)?

Answer 15

A system of membranes with ribosomes attached to its surface.

Question 16

What is the function of the rough endoplasmic reticulum (RER)?

Answer 16

Folds and processes proteins made by ribosomes.

Question 17

What is the structure of the smooth endoplasmic reticulum (SER)?

Answer 17

A system of membranes without ribosomes.

Question 18

What is the function of the smooth endoplasmic reticulum (SER)?

Answer 18

Synthesises and processes lipids.

Question 19

What is the structure of the cell wall in plants, algae, and fungi?

Answer 19

A rigid structure made of cellulose (plants and algae) or chitin (fungi).

Question 20

What is the function of the cell wall?

Answer 20

Provides structural support and prevents the cell from bursting under osmotic pressure.

Question 21

What is the structure of the cell vacuole in plants?

Answer 21

A membrane-bound organelle (tonoplast) containing cell sap, a weak solution of sugars, salts, and other substances.

Question 22

What is the function of the cell vacuole?

Answer 22

Maintains cell turgidity and stores nutrients and waste products.

Question 23

How are eukaryotic cells specialised in multicellular organisms?

Answer 23

They differentiate to perform specific functions by expressing different genes.

Question 24

How are specialised cells organised in multicellular organisms?

Answer 24

Specialised cells form tissues, tissues form organs, and organs form systems.

Question 25

Eukaryotic (eg human) cells compared with Prokaryotic (bacterium) (7)

Answer 25

1. Bacterial cell is much smaller than a human cell; (or human cell is much larger than a bacterial cell) 2. Bacterial cell has a cell wall but human cell does not; 3. Bacterial cell lacks a nucleus but human cell has a nucleus; 4. Bacterial cell lacks membrane-bound organelles but human cell has membrane-bound organelles; 5. Bacterial ribosomes smaller than human ribosomes / bacteria have 70S ribosomes whereas humans have 80S 6. Bacterial DNA is circular but human DNA is linear 7. Bacterial DNA is ‘naked’ whereas human DNA is bound to histones/proteins

Question 26

Eukaryotic - Describe the structure and function of the nucleus.(4)

Answer 26

Any four from Structure Nuclear envelope/double membrane (Nuclear) pores (in the membrane) Chromosomes/chromatin/(linear) DNA with histones Nucleolus/nucleoli Function Holds/stores genetic information for production of proteins DNA replication OR interphase Production of mRNA/tRNA OR transcription Production of rRNA/ribosomes;;;;

Question 27

Eukaryotic - Name the main polymer that forms the following cell walls – plants cells & fungal cells (1)

Answer 27

Cellulose (plant) and chitin (fungi);

Question 28

Eukaryotic - Describe the role of one named organelle in digesting these bacteria. (3)

Answer 28

1. Lysosomes; 2. Fuse with vesicle; Accept phagosome for vesicle 3. (Releases) hydrolytic enzymes;

Question 29

Eukaryotic - Identify two organelles in cells that enable the production of glycoproteins (1)

Answer 29

Rough endoplasmic reticulum/ribosomes and Golgi (apparatus/vesicles);

Question 30

Eukaryotic - Give two structures found in all prokaryotic cells and in all eukaryotic cells. (2)

Answer 30

1. Cell(-surface) membrane; 2. Ribosomes; Ignore 70S 3. Cytoplasm; 4. DNA;

Question 31

Eukaryotic – Give one feature of the chloroplast that allows protein to be synthesised inside the chloroplast and describe one difference between this feature in the chloroplast and a eukaryotic cell. (2)

Answer 31

Mark in pairs, 1 and 2 OR 3 and 4 1. DNA; 2. Is not associated with protein/histones but nuclear DNA is. OR Is circular but nuclear DNA is linear OR Is shorter than nuclear DNA; 3. Ribosomes; 4. Are smaller than cytoplasmic ribosomes;

Question 32

Eukaryotic - Eukaryotic cells produce and release proteins. Outline the role of organelles in the production, transport and release of proteins from eukaryotic cells.(4)

Answer 32

1. DNA in nucleus is code (for protein); 2. Ribosomes/rough endoplasmic reticulum produce (protein); Accept rER for ‘rough endoplasmic reticulum’ 3. Mitochondria produce ATP (for protein synthesis); 4. Golgi apparatus package/modify; OR Carbohydrate added/glycoprotein produced by Golgi apparatus; Accept body for ‘apparatus’ 5. Vesicles transport OR Rough endoplasmic reticulum transports; 6. (Vesicles) fuse with cell(-surface) membrane;

Question 33

Eukaryotic – state three differences between DNA in the nucleus of a plant cell and DNA in a prokaryotic cell.(3)

Answer 33

Plant v prokaryote 1. (Associated with) histones/proteins v no histones/proteins; 2. Linear v circular; 3. No plasmids v plasmids; Do not credit if suggestion that prokaryotic DNA only exists as plasmids. 4. Introns v no introns; 5. Long(er) v short(er);

Question 34

Eukaryotic – Name the main biological molecule in the cell membrane (1)

Answer 34

Phospholipids;

Question 35

Eukaryotic – Describe the role of mitochondria in secreting a protein (1)

Answer 35

(Many mitochondria) release energy / ATP for movement of vesicles / synthesis of protein / active transport;

Question 36

Eukaryotic – Describe the role of golgi apparatus in secreting a protein (1)

Answer 36

(Many Golgi) vesicles transport protein / glycoprotein / milk to cell membrane / out of cell;

Question 37

Eukaryotic – Describe the role of the golgi apparatus in lipid absorption

Answer 37

1. Modifies / processes triglycerides; 2. Combines triglycerides with proteins; 3. Packaged for release / exocytosis OR Forms vesicles;

Question 38

Outline the role of organelles in the production of proteins from eukaryotic cells.

Answer 38

1. DNA in nucleus is code (for protein); 2. Ribosomes/rough endoplasmic reticulum produce (protein); Accept rER for ‘rough endoplasmic reticulum’ 3. Mitochondria produce ATP (for protein synthesis);

Question 39

Outline the role of organelles in the transport and release of proteins from eukaryotic cells.

Answer 39

Golgi apparatus package/modify; OR Carbohydrate added/glycoprotein produced by Golgi apparatus; Accept body for ‘apparatus’ Vesicles transport