Chapter 6: A Tour of the Cell

Question 1

What is in the nucleus?

Answer 1

DNA (chromatin)

Question 2

What is the nuclear envelope?

Answer 2

Double membrane that protects the nucleus

Question 3

What is a nuclear pore?

Answer 3

A small hole in the nuclear envelope that allows the transport of proteins etc.

Question 4

What is a ribosome?

Answer 4

Protein builder / synthesizer

• composed of rRNA and protein

Question 5

What are the two types of ribosomes and what are their differences?

Answer 5

Free Ribosomes

• ribosomes that float around in the cytosol of the cell
• synthesize cytosolic proteins

Bound Ribosomes

• Ribosomes that are attached to the Rough ER (weird foldy thingy)
• synthesize membrane and secreted proteins

Question 6

What are the flattened sacs within the Rough ER called?

Answer 6

Cisternae

Question 7

What is the name of the fluid filled area within the Rough ER?

Answer 7

Lumen

Question 8

The Rough ER delivers proteins in __________________.

Answer 8

Transport vesicles

Question 9

What is the function of the Smooth ER?

Answer 9

• Make lipids
• Metabolize carbs
• Detoxify drugs
• Calcium storage

Question 10

Which one has ribosomes? The Smooth ER or the Rough ER?

Answer 10

Rough ER

Question 11

Explain Golgi apparatus processing and transport.

Answer 11

1. Rough ER sends out a vesicles to the cis face of the Golgi apparatus.
2. Each cisternae modifies the proteins and phospholipids and synthesizes polysaccharides using specific enzymes.
3. Cisternae matures as it transports vesicles from the cis face to the trans face
4. The trans face send the vesicles out to their designated part of the cell

Question 12

What are lysosomes?

Answer 12

Membranous sacs that do hydrolysis to break up polymers

They are very acidic

Question 13

What do lysosomes do?

Answer 13

• Digest food

- Vesicle forms around damaged organelles and lysosomes breaks it down and turns it into something useful

Question 14

Purpose of mitochondria?

Answer 14

Cellular respiration to generate energy in the form of ATP

Folding means there’s more membrane surfaces, more places to make ATP

Question 15

Purpose of chloroplasts?

Answer 15

Capture light energy for photosynthesis

Question 16

What are the components of a chloroplast?

Answer 16

• Thylakoids
• Thylakoid space
• Green pigment chlorophyll
• Stroma
• Intermembrane space

Question 17

What are thylakoids?

Answer 17

Flattened sacs, coated in pigment membranes where the light reactions take place.

Question 18

What is the thylakoid space?

Answer 18

The space is inside of the thylakoid.

Question 19

What is the stroma?

Answer 19

Liquid surrounding thylakoids

Question 20

What are microtubules? How do they grow?

Answer 20

Tubes made of tubulin protein

Grow by adding tubulin dimers to the +end
(-end is anchored at the centrosome)

+__________-
(••________)

•• = tubulin dimers added

Question 21

What are motor proteins and what do they do?

Answer 21

Proteins that walk along microtubules and carry cargo in a vesicles across the cell

Cargo can be chromosomes, proteins etc

Question 22

What is kinesin? What is dynein?

Answer 22

Kinesin - motor protein that walks towards - end

Dynein - motor protein that walks towards + end

Question 23

What are microfilaments? What do they do?

Answer 23

Strands made of actin in the cytoskeleton

Subunits (little actin proteins) are added to the +end and fall off of the -end

Question 24

What are intermediate filaments? What do they do?

Answer 24

Fibrous proteins that make coiled cables (looks like candy cane)

They reinforce shape of cells and fix position of organelles

Has keratin proteins

Question 25

What is the extracellular matrix (ECM)?

Answer 25

The space between cells that provides structure and support

Contains collagen

Question 26

What are cell junctions?

Answer 26

Physical connections between cells

In plants:
- plasmodeta

In animals:
- tight, anchoring, and gap junctions