Tour of the Cell

Question 1

Plasma Membrane

Answer 1

Membrane enclosing cell

Question 2

Endoplasmic Reticulum

Answer 2

Network of membranous sacs and tubes (cisternae); active in membrane synthesis and other synthetic and metabolic processes; has rough (ribosome-studded) and smooth regions

Question 3

Function of the endomembrane system?

Answer 3

Regulating protein traffic and performing metabolic functions in the cell

Question 4

What makes up the endomembrane system?

Answer 4

• Nuclear envelope
• Endoplasmic reticulum
• Golgi apparatus
• Lysosomes
• Various kinds of vesicles and vacuoles
• Plasma membrane

Question 5

How are membranes in the endomembrane system related?

Answer 5

Either through-

• Physical continuity
• By transfer of membrane segments as vesicles

Question 6

Vesicle

Answer 6

Sac made of membrane

Question 7

Internal Compartment of ER?

Answer 7

ER Lumen

Question 8

Smooth ER? Why called smooth?

Answer 8

Lacks ribosomes

Question 9

Rough ER? Why called rough?

Answer 9

Studded with ribosomes on outer surface of the membrane

Question 10

What does the smooth ER do?

Answer 10

• Synthesize lipids
• Metabolize carbohydrates
• Detoxify drugs and poisons
• Store calcium ions

Question 11

What does the RER do?

Answer 11

Make secretory proteins, acting as a membrane factory (making membrane proteins and phospholipids)

Question 12

Where do transport vesicles go after the ER?

Answer 12

Golgi apparatus

Question 13

What does the Golgi apparatus do?

Answer 13

Modifies, stores, and sends products of ER to other places; warehouse

Question 14

Cis Face

Answer 14

In Golgi stack; receives

Question 15

Trans Face

Answer 15

In Golgi stack; ships/sends

Question 16

How does the Golgi sort?

Answer 16

Add phosphate groups aka ID/Zip Code

Question 17

How does the Golgi ship?

Answer 17

External molecules (aka tour guides) that know the docking sites of surfaces of other organelles or plasma membrane

Question 18

Lysosome

Answer 18

Membranous sack of hydrolytic enzymes that hydrolyze (aka digest) macromolecules; aka stomach

Question 19

Where do lysosome enzymes work best?

Answer 19

Acidic environment on lysosome

Question 20

What if the lysosome leaked?

Answer 20

Not much will happen; pH of cytosol is near neutral

Question 21

What if a lot of lysosomes leaked a lot of enzymes?

Answer 21

Cell destroys itself by self-digesting

Question 22

Phagocytosis

Answer 22

When cells engulf/eat smaller organisms or food particles; carried out by lysosomes

Question 23

Human Cell Phagocytosis?

Answer 23

Macrophages–eat/destroy bacteria and invaders

Question 24

Autophagy

Answer 24

Process used by lysosome to recycle cell’s own organic material

Question 25

Why are lysosome super important?

Answer 25

Helps cell renew/rejuvenate itself

Question 26

Vacuoles

Answer 26

Large vesicles that come from the RER and Golgi; have a variety of functions

Question 27

How does the Endomembrane System flow?

Answer 27

ER to Golgi to elsewhere

Question 28

Any structural differences between ribosomes in the RER compared to the ones found in the cytoplasm?

Answer 28

Nope

Question 29

Cytoskeleton

Answer 29

Network of fibers that organizes structures and activities in the cell

Question 30

What does the cytoskeleton do?

Answer 30

Gives mechanical support to cell and maintains its shape; super important for animal cells (no cell walls); anchors organelles

Question 31

What's required for cell motility?

Answer 31

Interaction between cytoskeleton and motor proteins

Question 32

Microtubules

Answer 32

Thickest type of fiber that makes up the cytoskeleton

Question 33

Microfilaments

Answer 33

Aka actin filaments; thinnest fiber

Question 34

Intermediate Filament

Answer 34

Middle range fiber

Question 35

Function of Microtubules?

Answer 35

- Shape and support cell - Serve as tracks in which organelles with motor proteins can move - Compression resisting

Question 36

Centrosome

Answer 36

Located near nucleus; where microtubules grow out of

Question 37

Cilia and Flagella

Answer 37

Have microtubules extending that help move the cell

Question 38

Function of Microfilaments?

Answer 38

- Support cell shape - Tension bearing - Form structural networks

Question 39

Function of Intermediate Filaments?

Answer 39

- Reinforce cell shape - Bear tension - Fix positions of organelles

Question 40

Function of ECM?

Answer 40

Coordinate behavior of cell(s)