Week 1: tour de cell

Question 1

What are the main types of membrane proteins? What are they used for?

Answer 1

• Transport proteins
• Signalling proteins
• Joining cells
• Enzymes

Question 2

What’s a nucleolus?

Answer 2

A nucleolus hangs out in the nucleus producing components of ribosomes.

A nucleus may contain 1-3

Question 3

What are 3 key ways animal cells communicate?

Answer 3

Animal cells can communicate using…

• Tight junctions
• Desmosomes
• Gap junctions

Question 4

What is the structure of the plasma membrane?

Answer 4

The plasma membrane is made of phospholipids in a fluid mosaic, cholesterol, proteins, and carbohydrates.

Question 5

Function of a vacuole?

Answer 5

Vacuoles serve to control water content of the cell (more in plants) and manage waste (more in animals).

Question 6

How many mitochondria in a cell?

Answer 6

1000s

Question 7

What are cristae?

Answer 7

The mitochondrial internal membrane is folded into cristae to increase surface area.

Question 8

What are the two internal compartments of a mitochondria?

Answer 8

Inside a mitochondria are the intermembrane space and the matrix.

Question 9

Function of perixisomes/microbodies?

Answer 9

Perixisomes/microbodies ccumulate toxic waste products

Question 10

Function of the nucleolus?

Answer 10

The nucleolus is where components of ribosomes are made

Question 11

What are the two key components of the endomembrane system?

Answer 11

The endomembrane system is made up of the

• Endoplasmic reticula
• The golgi apparatus

Question 12

Function of a lysosome?

Answer 12

Lysosome works in digestion + waste removal

Question 13

Function of the cytoskeleton?

Answer 13

• Cytoskeleton serves to…
  
  • -> Give cell structure and reinforce shape
  • -> Anchorage points for organelles

Question 14

Function of the mitochondria?

Answer 14

Purpose of the mitochondria is to produce ATP

Question 15

Function of ribosomes?

Answer 15

Ribosome function is protein synthesis

Question 16

Function of ER?

Answer 16

ER function is synthesis of proteins, lipids, other molecules

Question 17

Function of golgi body?

Answer 17

Golgi body function:

–> Processing and packaging proteins and lipid

Question 18

What are the three structural units of the cytoskeleton? What are they made of?

Answer 18

Cytoskeleton is made of 3 components:

• Microfilaments (actin)
• Intermediate filaments (fibrous subunits)
• Microtubules (tubulin proteins)

ALL are important for cell shape

Question 19

Role of microfilaments in the ctyoskeleton?

Answer 19

Microfilaments sit just inside the membrane and can…

• Bear tension
• Resist pulling force
• Useful for cytoplasmic streaming, muscle contractions, cell shape, cell division, movement of amoeba, formation of cleavage narrow for division

Question 20

Role of intermediate filaments in the cytoskeleton?

Answer 20

Intermediate filaments are made of fibrous proteins (from the keratin family) supercoiled into thick cables.

• Important for cell shape + anchoring organelles
• UNLIKE OTHERS: not dissasembled + reassembled: permant shape + position

Question 21

Role of microtubules in the cytoskeleton?

Answer 21

Microstubules..

• Are the major component of cilia, flagella and centrioles
• Resist compression
• Are important for cell shape, motility, chromosome + organelle movement
• Can act as highway for vesicles (which move helped by motor proteins powered by ATP)

Question 22

What is the structure of flagella?

Answer 22

Flagella contain 9 doublets and 2 singles of microtubules.

Question 23

How are microtubules involved in cell division?

Answer 23

The centrosome is the area near nucleus that radiates microtubules, acting as compression-resistant girdles.