Cytoskeleton

Question 1

Draw/describe microtubules, including:
o Subunit types

Answer 1

Alpha and beta tubulin

Question 2

▪ Basal bodies – Where are they found? What do they do?

Answer 2

Base of cilium/flagellum, anchor point for cilia and flagella

Question 3

▪ Centrioles/MTOCs – Where are they found? What do they do?

Answer 3

Part of centrosomes, anchor points for more microtubules than the basal bodies

Question 4

▪ Axonemes – Where are they found? What do they do?

Answer 4

Move cilia or whole cell in case of flagella

Question 5

Types of IF

Answer 5

Keratin, laminin

Question 6

• Draw/describe micro/actinfilaments, including:
  o Subunit types

Answer 6

Actin subunits

Question 7

Microfilaments vs actin filaments

Answer 7

SAME THING

Question 8

Microtubule Subunits incorporated into polymer

Answer 8

GTP-αβ-tubulin heterodimer

Question 9

IF Subunits incorporated into polymer

Answer 9

~70 different proteins, likely incorporated as tetramers

Question 10

Actin/microfilament Subunits incorporated into polymer

Answer 10

ATP-actin monomers

Question 11

Microtubule Preferential site of incorporation

Answer 11

+ end (beta tubulin)

Question 12

IF Preferential site of incorporation

Answer 12

Internal

Question 13

Actin/microfilament Preferential site of incorporation

Answer 13

+ end (barbed)

Question 14

What has polarity/

Answer 14

Microtubules/actin filaments

Question 15

What doesn’t have polarity?

Answer 15

IF

Question 16

Miccrotubule enzymatic activity

Answer 16

GTPase

Question 17

IF enzymatic activity

Answer 17

None

Question 18

Actin/Microfilament enzymatic activity

Answer 18

ATPase

Question 19

What motor proteins associate with microtubules?

Answer 19

Kinesins, dyneins

Question 20

What motor proteins associate with IFs?

Answer 20

None

Question 21

Major groups of associated proteins with microtubules

Answer 21

MAP

Question 22

Major groups of associated proteins with IF

Answer 22

Plakins

Question 23

Major groups of associated proteins with actin/microfilaments

Answer 23

Actin binding proteins, Myosin

Question 24

Structure of microtubules

Answer 24

Stiff, hollow, inextensible tube

Question 25

Structure of IF

Answer 25

Tough, flexible, extensible filament

Question 26

Structure of actin/microfilaments

Answer 26

Flexible, inextensible helical filament

Question 27

Microtubule dimensions

Answer 27

25 nm outer tube diameter

Question 28

IF dimensions

Answer 28

10-12 nm tube diameter

Question 29

actin/microfilament dimensions

Answer 29

8 nm diameter

Question 30

What species are microtubules found in?

Answer 30

Eukaryotes

Question 31

What species are IF found in?

Answer 31

Animals

Question 32

What species are actin/microfilaments found in?

Answer 32

Eukaryotes

Question 33

Primary functions of microtubules

Answer 33

support, intracellular support, cell organization

Question 34

Primary functions of IF

Answer 34

Structural support, mechanical strength

Question 35

Primary functions of actin/microfilaments

Answer 35

Motility, contractility, intracellular transport

Question 36

What part of the cell are microtubules found in?

Answer 36

Cytoplasm

Question 37

What part of the cell are IF found in?

Answer 37

Cytoplasm and nucleus

Question 38

What part of the cell are actin/microfilaments found in?

Answer 38

Cytoplasm

Question 39

* Draw/describe intermediate filaments, including: o Arrangement – Figure 9.36 gives a quick view

Answer 39

multiple strands of fibrous proteins wound together, each consisting of amino acids arranged in a chain

Question 40

Draw/describe microtubules, including: o Arrangement

Answer 40

The wall consists of 13 protofilaments composed of αβ-tubulin heterodimers stacked in a head-to-tail arrangemen

Question 41

Draw/describe microtubules, including: o General structure

Answer 41

13 protofilaments in a ring (alpha and beta tubulin subunits)