1.2b - The Synthesis and Transport of Proteins

Question 1

Eukaryotic cells have a system of internal membranes which…

Answer 1

increases the total area of membrane

Question 2

Because of their size, eukaryotes have a relatively small…

Answer 2

surface area to volume ratio

Question 3

The plasma membrane of eukaryotic cells is too small an area to…

Answer 3

carry out all the vital functions carried out by membranes

Question 4

The endoplasmic reticulum (ER) forms a…

Answer 4

network of membrane tubules continuous with the nuclear membrane

Question 5

The Golgi apparatus is…

Answer 5

a series of flattened membrane discs

Question 6

Lysosomes are…

Answer 6

membrane-bound organelles

Question 7

Lysosomes contain…

Answer 7

a variety of hydrolases that digest proteins, lipids, nucleic acids and carbohydrates

Question 8

Vesicles transport materials between…

Answer 8

membrane compartments

Question 9

Lipids and proteins are synthesised in the

Answer 9

ER

Question 10

The Rough ER (RER) has…

Answer 10

ribosomes on its cytosolic face

Question 11

The Smooth (SER)…

Answer 11

lacks ribosomes

Question 12

Lipids are synthesised in the SER and inserted…

Answer 12

into its membrane

Question 13

The synthesis of all proteins begins in…

Answer 13

cytosolic ribosomes

Question 14

The synthesis of cytosolic proteins is completed in…

Answer 14

the cytosolic ribosomes

Question 15

Cytosolic proteins remain in the…

Answer 15

cytosol

Question 16

Transmembrane proteins carry a signal sequence, which…

Answer 16

halts translation and directs the ribosome synthesising the protein to the dock with the ER, forming RER

Question 17

Translation continues after docking, and the protein is…

Answer 17

inserted into the membrane of the ER

Question 18

Once the proteins are in the ER, they are…

Answer 18

transported by vesicles that bud off from the ER and fuse with the Golgi apparatus

Question 19

As proteins move through the Golgi apparatus…

Answer 19

they undergo post-translational modification

Question 20

Molecules move through the Golgi discs in…

Answer 20

vesicles that bud off from one disc and fuse to the next one in the stack

Question 21

Enzymes catalyse the addition of various sugars in multiple steps to…

Answer 21

form the carbohydrates

Question 22

Vesicles that leave the Golgi apparatus take proteins…

Answer 22

to the plasma membrane and
lysosomes

Question 23

Vesicles move along the microtubules and…

Answer 23

fuse with them within the cell

Question 24

Secreted proteins are…

Answer 24

translated in ribosomes on the RER and enter its lumen

Question 25

2 examples of secreted proteins

Answer 25

peptide hormones and digestive enzymes

Question 26

The proteins move through the Golgi apparatus and are then…

Answer 26

packaged into secretory vesicles

Question 27

Many secreted proteins are synthesised as…

Answer 27

inactive precursors and require proteolytic cleavage to produce active proteins

Question 28

Proteolytic cleavage is a type of…

Answer 28

post-translation modification

Question 29

Digestive enzymes are one example of…

Answer 29

secreted proteins that require proteolytic cleavage to become active