BIOA01H3 Lecture Notes - Lecture 4: Cytoskeleton, Tubulin, Cytosol

25 views2 pages

pucejellyfish31

5 Nov 2016

School

Department

Course

Professor

For unlimited access to Class Notes, a Class+ subscription is required.

3363410481 and 37710 others unlocked

BIOA01H3 Full Course Notes

Verified Note

18 documents

Document Summary

Sorting signal is recognized by receptor on protein, moves it to e. r, if not, then is made in cytosol. If it goes in er, can go to. Cells differ in size and shape reflects their function play critical role for the protein fibers of the cytoskeleton to provide internal support to maintain the shape of eukaryotic cells. Shape of cell is determined by function of cell (eg. neurons compared to dermal cells), cytoskeleton is very important prok don"t have cytoskeleton. All eukaryotic cells have microtubules (mt) (composed of tubulin) and microfilaments (composed of actin) remain unchanged throughout evolution (75-80% amino acid identity across organisms) cytoskeleton intermediate filaments protein subunits provide structural support. All three are long chains made up of specific changes in shape, assist in mitosis/cell division. Thickness: tubulin > intermediate > actin movement of substances within cells, assist in. Intermediate filaments are not identical in all cells (eg. diff in fibroblasts than in neurons)

Related Questions

i need help with this homwork please choose the correct answers and just be claer to read and understand for the slect the apply qusestions too and it is important i realy need the right answers so please be claer not write randomly i really need the correct answers to study for my test so hop you can help me

Question 1

What is the smallest cell you could find?

Question 2

TEMs appear as 3D images

True

False

Question 3

Bacteria are what cell type? Write one word as the answer in lowercase and using no syntax.

Flag this Question

Question 42 pts

ALL eukaryotic cells have which of the following. Click all that apply.

membrane enclosed cell organelles

mitochondria

Question 5

Prokaryotes and eukaryotes both have which if the following cellular components. Click all that apply.

Question 6

I am made of one 60s and one 40s subunit, which organelle am I?

protein

lipid

bacterial ribosome

Question 9

The difference between the rough and smooth ER is

the rough produces lipids where as the smooth does not

the rough has many folds and convolutions where as the smooth does not

the rough has ribosome embedded and the smooth does not

the rough is closer to the cell membrane whereas the smooth is closer to the nucleus

Question 10

The site where many lipids, including cell membrane is produced.

Question 11

Name the organelle: In muscle cells in particular, I would increase in number and size in response to frequent exercise

Question 12

In animal cells, glucose would be mobilized from its storage molecule (glycogen) in this part of the cell.

Question 13

Which of these is associated with the rough ER

production of carbohydrates

production of steroid hormones

production of ATP

production of proteins that are secreted from the cell

Question 14

Which organelle sorts, modifies and stores substances produced on the rough ER. Write two words as the answer in lower case separated by a space.

Question 15

Which organelle is responsible for ATP production. Write one word in the singular as the answer.

Question 16

You inherit all of your mitochondria from your

father

half from your mother and half from your father

your siblings

mother

Question 17

An organelle that contains chlorophyll

Question 18

Microtubules have a variety of roles, which of the options below is NOT one of them?

separate chromosomes

cilia and flagellum movement

tracks for organelle movement

constrict the cell during cell division

Question 19

Made of tubulin subunits

microfilaments

chromosomes

intermediate filaments

microtubules

Question 20

Name the part of the cytoskeleton that is made of two twisted rods of actin. Write one word as the answer in lower case.

Question 21

Which part of the cytoskeleton is made of the same protein as your hair and nails?

microfilaments

microtubules

Intermediate filaments

Question 22

The extracellular matrix is found outside of, but attached to the cell membrane?

True

False

Question 23

Which of the options below is an important function of the extra cellular matrix?

connecting cells together

regulate the movement of substances into and out of the cell

helping cells divide into two cells

keeping the cell in a fixed and ridged shape

Question 24

Which part of the cell wall has a high pectin content?

Question 25

Plants have mitochondria, chloroplasts, a cell wall, and nuclei.

True

False

Question 27

What accounts for 40% of the protein in our bodies?

Question 28

Animal cells have cell walls

True

false

1. Name two similarities and two differences between thecellular processes of importing

protein into the ER and importing protein to the nucleus.

2. What proteins are directly involved in the transportation ofcargo in a clathrin-coated

vesicle?

a. Dynamin

b. Adaptins

c. Cargo receptors

d. t SNARES

3. Suppose a cell was treated with colchiine, a drug causingmicrotubule disassembly.

What would happen within the cell? Why?

Suppose there were a genetic defect in the genes that code forkinesins and dyneins.

What would happen within the cell? Why?

4. Which of the following are true about microtubules?

a. They are utilized by the disease causing bacteriaLysteria.

b. Instability in the minus-end of the microtubule is caused bythe hydrolization of GTP.

c. Centrosomes contain binding sites for microtubules composed atype of tubulin ring.

d. Cellular concentrations of tubulin are above the criticalconcentration for plus-end

polymerization.

e. Motor proteins can attach organelles to the microtubules.

5. Indicate which of the following statements are false:

a. Membrane fusion is energetically unfavorable and thusrequires ATP or similar high

energy molecule to occur

b. Clathrin is responsible for capturing specific molecules fortransport in coated vesicle

structures.

c. Receptor proteins that are incorporated into an endosome canbe retrieved back to the

membrane domain it originated from; can return to a new domainof the membrane; or

can enter the lysosome for digestion.

d. Transport vesicles occasionally bud from the trans Golginetwork to fuse with the

plasma membrane in a process called constitutive exocytosis.

e. Most components of the endocytic vesicle membrane eventuallyare returned to the

plasma membrane for reuse.

6. Match the following organelles with their function:

Organelle Bank:

a. Mitochondria

b. Endoplasmic reticulum

c. Nucleus

d. Lysosome

e. Endosome

f. Peroxisome

g. Golgi apparatus

_____ quality control of mRNA

_____ location of oxidative phosphorylation

_____ responsible for detoxifying organic molecules (livercells)

_____ houses and protects genetic material

_____ responsible for modification and sorting of proteins andlipids

_____ location of ATP synthesis

_____ responsible for sorting endocytosed materials

_____ site of degradation and digestion

_____ responsible for oxidizing toxic molecules

_____ location of lipid synthesis

_____ location of hormone synthesis (adrenal cells)

B. Which organelle(s) from the above list communicate(s) withother organelle(s)

through the use of vesicular transport? ________________

C. Which organelle(s) from the above list receive proteins madein the

cytosol?___________________

D. Through which organelle(s) must proteins pass to reach theorganelle(s) which do not

receive proteins made exclusively in thecytosol?______________

E. Entrance into which organelle(s) requires that proteinsunfold and snake through the

membrane? _________________

F. How do organelles maintain their position in the cytosol? Bespecific.

G. Give 2 advantages that eukaryotic cells gain by havingorganelles.

7. Which of the following statements are true regardingactin?

a. They are arranged in a

crimsonwalrus870

The vesicles that transport materials from donor membranes to acceptor membranes include:

	1.	COP-II coated vesicles
	2.	COP-III coated vesicles
	3.	COP-I coated vesicles
	4.	Clathrin coated vesicles

2.5 points

QUESTION 11

During skeletal muscle contraction, the roles of ATP include:

	1.	ATP is not required for forming the crossbridges between myosin and actin filaments.
	2.	ATP is utilized as a structural linker to mediate the interaction between myosin and actin filaments
	3.	Hydrolysis of ATP provides energy for myosin head to move along actin filaments and the binding of ATP to myosin head allows the detachment of myosin fromactin filaments.
	4.	ATP binds to actin filaments to drive the power stroke of myosin head.

2.5 points

QUESTION 12

One of the functions of smooth endoplasmic reticulum is

	1.	Synthesizing steroid hormone in the endocrine cells of the gonad and adrenal cortex
	2.	Serves as the starting point of the biosynthetic pathway
	3.	Synthesizing secretory proteins
	4.	Degrading cell debris

2.5 points

QUESTION 13

The function of COP-II coated vesicles is mainly:

	1.	Transporting materials from endosomes to Golgi complex
	2.	Moving materials from the ER to the ERGIC and Golgi complex.
	3.	Transporting materials from Golgi complex back to endoplasmic reticulum.
	4.	Involved in receptor-mediated endocytosis.

2.5 points

QUESTION 14

Which of the following processes is completed in rough endoplasmic reticulum?

	1.	Chaperones help misfolded proteins fold correctly.
	2.	Proteins that target to nucleus are synthesized in rough endoplasmic reticulum.
	3.	O-linked glycosylation occurs in rough endoplasmic reticulum.
	4.	Misfolded proteins are destructed in rough endoplamic reticulum.

2.5 points

QUESTION 15

Kinesin is the motor protein that coorporates with microtubules. It has the following functions:

	1.	It uses GTP as energy source.
	2.	It can hydrolyze ATP and use the energy to drive cargo along microtubules from minus end to plus end.
	3.	It has a globular head that can act as GTPase
	4.	The tail of kinesin is more diverse and binds to cargo

2.5 points

QUESTION 16

For correct segregation and trafficking, lysosomal proteins are tagged in the cis-Golgi with phosphorylated mannose residues, and then the tagged lysosomal enzymes are recruited to clathrin coated vesicles by mannose 6-phosphate receptors.

True

False

2.5 points

QUESTION 17

The process that specialized cells, such macrophages, engulf relatively large particles is:

	1.	Called pinocytosis
	2.	Called phagocytosis
	3.	Mediated by COP-II coated vesicles
	4.	Called autophagy

2.5 points

QUESTION 18

Proteins synthesized on rough endoplasmic reticulum and smooth endoplasmic reticulum are imported co-translationally to their destinations

True

False

2.5 points

QUESTION 19

Treatment of cells with a drug that promotes microtubule disassembly disperses Golgi complex into separate stacks of membrane compartments, suggesting that:

	1.	Golgi complex is made of microtubules.
	2.	Microtubules are important for the organization of Golgi complex.
	3.	Microtubules are transported into Golgi complex
	4.	Golgi complex is composed of tubulin proteins

2.5 points

QUESTION 20

Which of the following is correct about signal sequence of a secretory protein?

	1.	It is an âaddress codesâ for protein trafficking pathways
	2.	It is usually located at the C-terminus.
	3.	It targets the ribosome and the protein that is being synthesized to endoplasmic reticulum.
	4.	It is removed in Golgi complex.

apricotgrasshopper117

BIOA01H3 Lecture Notes - Lecture 4: Cytoskeleton, Tubulin, Cytosol

BIOA01H3 Full Course Notes

Document Summary

Get access

Related Documents

BIOA01H3 Lecture Notes - Lecture 16: Cytoskeleton, Lysosome, Cell Membrane

BIOA01H3 Lecture Notes - Lecture 4: Signal Recognition Particle, Nuclear Localization Sequence, Protein Targeting

BIOA01H3 Lecture Notes - Lecture 4: Tubulin, Intermediate Filament, Depolymerization

Related Questions