Chapter 2- Cell Structure

Question 1

Function of smooth ER?

Answer 1

• lipid + carbohydrate synthesis

- storage

Question 2

Function of lysosome?

Answer 2

• contains hydrolytic enzymes

- break down organelles, pathogens, cells

Question 3

Function of ribosome?

Answer 3

Protein synthesis

Question 4

Features of plant cells that are not features of animal cells?

Answer 4

• vacuole
• chloroplast
• cell wall

Question 5

Features of animal cell that are not present in plant cells?

Answer 5

• centrioles

- lysosomes

Question 6

Role of cytoskeleton?

Answer 6

• maintains shape
• holds organelles in place
• movement of chromosomes in cell
• provides strength

Question 7

how do organelles work together to produce and release protein molecules from cells?

Answer 7

• nucleus contains gene for protein. This is site of transcription
• Ribosome on RER site of protein synthesis
• vesicle transports protein to Golgi apparatus
• this modifies and repackages proteins
• another vesiclescontaining proteins fuse with CSM

Question 8

Function of mitochondria?

Answer 8

Involved in aerobic respiration and produces ATP

Question 9

Detail of organelle could not be seen clearly with light microscope. Why?

Answer 9

• too small

- resolution not high enough

Question 10

advantages of staining specimens?

Answer 10

• increases contrast

- allows organelles to be identified

Question 11

Types of extra cellular proteins secreted?

Answer 11

• hormones
• enzymes
• glycoproteins

Question 12

State stages during secretion of protein that require energy

Answer 12

• transporting vesicle to CSM

- exocytosis

Question 13

Role of Golgi apparatus?

Answer 13

• receives ribosomes from RER in vesicles
• modifies and repackages proteins in vesicles
• makes lysosomes
• lipid synthesis

Question 14

Features in prokaryotic cells but not in eukaryotic cells?

Answer 14

• circular DNA
• plasmids
• 70s ribosomes

Question 15

Added water to slide with blood. Cell burst
Added water to slide with epidermal cell. Did not burst.
Why?

Answer 15

• cell cytoplasm has lower water potential than water
• water moves into both cells down water potential gradient
• water moves into cell by osmosis
• CSM of blood cannot withstand pressure and bursts
• epidermal cell has cell wall that can withstand pressure and becomes turgid

Question 16

How to prevent cell bursting when looking under microscope?

Answer 16

Use solution with similar water potential

Question 17

What is magnification?

Answer 17

The no. of times larger the image is to the object

Question 18

What is resolution?

Answer 18

The ability to distinguish between two points and see detail

Question 19

How do images taken with SEM turn out?

Answer 19

• 3D images

- can see surface

Question 20

Function of nuclear pores?

Answer 20

Allow molecules to move in and out of nucleus

Question 21

Describe how the ultrastructure of neutrophil is specialised to enable the engulf and digestion of foreign cells

Answer 21

• many lysosomes
• many ribosomes
• many mitochondria
• many receptors on CSM

Question 22

Function of chloroplasts?

Answer 22

Site of photosynthesis

Question 23

Name structures associated with the cytoskeleton which bring about cell movement

Answer 23

• microtubules
• microfilaments
• flagella
• cilia

Question 24

Processes inside cells that require cytoskeleton for movement?

Answer 24

• cytokinesis

- movement of chromosomes

Question 25

Suggest why 2 mitochondria look different?

Answer 25

- cut in diff planes | - mitochondria still growing

Question 26

How are vesicles moved from one organelle to another?

Answer 26

- move along microfilaments and microtubules | - using ATP

Question 27

Why nuclear envelope has pores?

Answer 27

- allow movement of molecules in and out of nucleus | - e.g. mRNA out of nucleus

Question 28

Advantages of staining (image included)

Answer 28

- increases contrasts | - organelle X can now be seen

Question 29

Intermediate fibres?

Answer 29

- gives mechanical strength | - maintains integrity of cell

Question 30

Microfilaments?

Answer 30

- contractile fibres - made from actin - responsible for cel movement - e.g. cell contraction in cytokinesis

Question 31

Microtubules?

Answer 31

- globular tubulin proteins polymerise to form tubes - form scaffold like structures - determines shape of cell - e.g. spindle fibres

Question 32

Empty magnification?

Answer 32

-magnification increased without increase in resolution so no more detail visible

Question 33

Role of vacuole?

Answer 33

Storage

Question 34

What are the organelles like in eukaryotic cells?

Answer 34

Membrane bound AND non membrane bound

Question 35

What does mitochondria contain?

Answer 35

Circular DNA

Question 36

Diameter of eukaryotic cell?

Answer 36

20-40 micrometers

Question 37

Diameter of prokaryotic cell?

Answer 37

0.5-5 micrometers

Question 38

How big are the ribosomes in eukaryotic cells?

Answer 38

- 80s | - 22nm

Question 39

How big are the ribosomes in prokaryotic cells?

Answer 39

- 70s | - 18nm

Question 40

Does lysosome have an envelope?

Answer 40

No

Question 41

How many membranes does chloroplast have?

Answer 41

2

Question 42

Organelle extracted and kept in sucrose solution. Purpose of sucrose solution?

Answer 42

Prevents organelle from changing shape

Question 43

How images with transmission electron miscroscope are?

Answer 43

- 2D | - internal details visible

Question 44

Roles of the cytoskeleton?

Answer 44

- make up spindle fibres - provide strength - determine shape - movement of organelles - hold organelles in place