Non-enzymatic Protein Function (5/15)

Question 1

Cytoskeleton function

Answer 1

Shape and structure
Motion
Cell division
Organelle and biomolecule transport

Question 2

Actin

Answer 2

forms the microfilaments of the cytoskeleton and is very abundent

Question 3

Actin in microfilaments: function

Answer 3

motion
structure
cell division
muscle contraction

Question 4

Individual actin monomers

Answer 4

G-actin because they have a globular shape and posses a site where ATP or ADP can bind

Question 5

When a ton of G-actin bind together…

Answer 5

It forms F-actin which stands are filamentous actin and two of these stick together to form a microfilament

Question 6

Rapid growth and disassembly

Answer 6

when polymerization= depolymerization, we have tread-milling and when we want to stop, we have capping proteins

Question 7

Intermediate filaments

Answer 7

a long alpha-helical section

very flexible: can be stretched

Question 8

Where are intermediate filaments found?

Answer 8

in the cytoplam

Question 9

What is the main function of intermediate filaments?

Answer 9

structural support
cell adhesion
organelle positioning

Question 10

Microtubules

Answer 10

structural support for cilia and eukaryotic flagella
chromosome separation during mitosis and meiosis
intracellular transport

Question 11

Subunit of microtubules

Answer 11

tubulin dimer consisting of an alpha-tubulin and a beta-tubulin
bring GTP or GDP

Question 12

Motor protein functions

Answer 12

transport
motility
muscle contraction

Question 13

Kinesins

Answer 13

ATP-ases

consumes energy from ATP hydrolysis

Question 14

Direction of kinesins

Answer 14

move to + end of microtubules which is to the periphery and this is called anterograde transport

Question 15

Make up of kinesins

Answer 15

heterotretramers
made of of 4 subunits that are not all the same
2 subunits: heavy chains, with two head groups that are the feet
2 other subunits: light chains

Question 16

How kinesins move

Answer 16

ATP binds head to the microtubule causing a conformational change and swing with other head bound to ADP forward (ADP has head be detacted)

Question 17

Direction of dyneins

Answer 17

move to the cell center to the minus end and is called retrograde transport

Question 18

Axonemal dyneins

Answer 18

found in cells with only cilia or flagellum

Question 19

Cytoplasm dyneins

Answer 19

transport cargo for cell function

Question 20

Myosins

Answer 20

ATP-ases

main job: muscle contraction

Question 21

What myosins are composed of

Answer 21

head, neck, and tail domains

Question 22

Cell adhesion molecules types

Answer 22

selectins, cadherins, integrins

Question 23

Selectins

Answer 23

mediated inflammatory cells: platelets and endothelial cells

Question 24

How selectins works

Answer 24

cytokines express selectins. luekocytes stick to selectins to slow them down and do reaction
Heterophilic and Ca2+ dependent

Question 25

Cadherins

Answer 25

cell growth and development | calcium ions, span entire cell membrane, transmembrane

Question 26

Integrins

Answer 26

adheres to extracellular matrix and cell signaling location: cell membrane Action: binds ligands and cations

Question 27

Cell junctions

Answer 27

anchoring junctions gap junctions tight junctions

Question 28

Anchoring junctions

Answer 28

connect cytoskeleton of one cell with the cytoskeleton of another or extracellular matrix

Question 29

Adherens junction and desmosomes

Answer 29

types of anchoring junctions

Question 30

Gap junctions

Answer 30

connexin which links the cytosol of neighboring cells. facilitates cell-to-cell communication

Question 31

What can pass through gap junctions?

Answer 31

amino acids, vitamins, sugars, nucleotides, Ca2+, and cAMP

Question 32

Tight junctions

Answer 32

in epithelial cells and do not allow anything but water and some ions contain occludin and claudin EX) blood brain barrier

Question 33

Regions of an antibody

Answer 33

constant region, variable regions, and hypervariable regions (where antigens bind)

Question 34

Isotypes of antibodies

Answer 34

different kinds of antibodies

Question 35

IgA

Answer 35

in gut, blocks pathogens and respiratory tract

Question 36

IgD

Answer 36

b cells

Question 37

IgE

Answer 37

allergic and anti-parasitic immunity

Question 38

IgM

Answer 38

early response

Question 39

IgG

Answer 39

eliminates bacterial and viral pathogens (most common)- only ones to cross placental membrane

Question 40

Class switching

Answer 40

b-cells and change isotypes by changing heavy change but keeping hypervariable region