Physiology 3

Question 1

What is intermediate filament? What are examples of specific filament?

Answer 1

filamentous structure that helps provide tissue specificity and helps with cell type identification

GFAP in astrocytes
neurofilament in neurons

Question 2

What are microtubules?

Answer 2

building block tubulin that provides structural support and subcellular motility

Question 3

Microtubules grow more rapidly at its _____ end. What is the term for rapid growth and shrinkage of microtubules?

Answer 3

plus

dynamic instability

Question 4

When rate of polymerization of GTP is fast and hydrolyzation is slow, microtubules will (grow/shrink)

Answer 4

grow

Question 5

Dynein acts as a…

Answer 5

molecular motor to power ciliary and flagellar movement

Question 6

The ____ arms restrict the extent to which neighboring microtubules can move with respect to each other

Answer 6

nexin

Question 7

What compound provides the force necessary to move membrane-bound organelles through the cytoplasm along microtubular tracks?

Answer 7

dynein-kinesin

Question 8

______-______ vesicles move from microtubular minus ends (originate at _______) to plus end (_____ ______). The direction of movement is called…

Answer 8

kinesin-bound

centrosomes

axonal terminals

anterograde fast axonal transport

Question 9

______-_______ vesicles move cargo from axonal terminals (____) towards centrosomes (______). This is called…

Answer 9

dyenin-bound

plus

negative

retrograde transport

Question 10

Both retrograde and anterograde fast axonal transport require…

Answer 10

ATP

Question 11

What is the name for polymers of actin?

Answer 11

thin filament OR microfilament

Question 12

What is treadmilling of microfilament?

Answer 12

length of filament remains CONSTANT

as the polymer grows at plus end, it disassembles at minus end

Question 13

What is an example of thick filament? What is something important it does?

Answer 13

myosin

utilize ATP to bend and assist in muscle contraction

Question 14

Thick filaments have ____ tails and _____ head groups to act as _____ along actin filaments

Answer 14

helical

globular

motors

Question 15

What are the 6 main organelles of the cell we will be discussing?

Answer 15

1) lysosomes
2) peroxisomes
3) mitochondria
4) endoplasmic reticulum
5) Golgi Apparatus
6) nucleus

Question 16

What is the organelle nicknamed “the cells trash digester”? Why is it called this?

Answer 16

lysosomes

filled with digestive hydrolases that remove damaged cellular structures, unwanted abcteria, etc

Question 17

_________ contain oxidases instead of typical hydrolases in enzymes. What do they do?

Answer 17

peroxisomes

-oxidation of long to short-chain fatty acids
-convert cholesterol into bile acids

Question 18

Where does ATP production occur? Where is the DNA for this organelle inherited from and where do the proteins originate?

Answer 18

mitochondria

maternal

nuclear DNA

Question 19

What is the difference between rough ER and smooth ER (both composition and function)?

Answer 19

rough ER has attached ribosomes, smooth does not

-rough ER synthesizes new proteins
-smooth ER metabolizes drugs/toxic chemicals and synthesizes hydrophobic molecules like steroids

Question 20

Which organelle is prominent in secretory cells? What does it do?

Answer 20

golgi apparatus

-modifies proteins
-sort/distribute proteins

Question 21

When modifying proteins
the _____ end of golgi apparatus receives immature protein, while the trans end secretes _______ proteins

Answer 21

cis

mature

Question 22

Endocytosis is mediated by 2 things. What are they and what do they do?

Answer 22

1) clathrin
-mediates formation of secretory vesicles that leave trans Golgi

2) calveoli
-facilitates clathrin-independent endocytosis

Question 23

Which organelle store genetic material and is the site of RNA synthesis? What are the 2 components of it?

Answer 23

nucleus

1) chromatin
2) nucleoli

Question 24

What is the chromatin? What are the 2 subcategories?

Answer 24

complex of DNA and DNA-binding proteins

1) euchromatin
2) heterochromatin

Question 25

What is loosely packed chromatin in the nucleus?

Answer 25

euchromatin gene-rich and transcriptionally active

Question 26

What is heterochromatin?

Answer 26

densely packed chromatin gene-poor and transcriptionally silent

Question 27

What is the site of transcription of ribosomal RNA?

Answer 27

nucleoli