Non Enzymatic Protein Function

Question 1

the affinity of a ligand and a receptor is measured by

Answer 1

a dissociation contanst, Kd

Question 2

Kd represents the concentration of ligand that is required for ___

Answer 2

50% binding

Question 3

Lower Kd indicates _____ affinity

Answer 3

stronger

Question 4

_____ span the entire bilayer of the membrane allowing for the passage of ions from 1 side of the membrane to the other

Answer 4

ion channels

Question 5

Ion channels have an ____ pore, which becomes accessible to ions after a _____ in the protein structure that causes the ion channel to open

Answer 5

aqueous, conformational change

Question 6

proteins can bind certain molecules based on their ___ and ____

Answer 6

affinity and specificity

Question 7

the affinity determines ____ binds to the protein while specificity determines ____ will bind to the protein

Answer 7

how readily a molecule, which molecule

Question 8

Antibodies are protein molecules that are involved in the ______ of the body.

Answer 8

immune system

Question 9

antibodies bind to specific ____ on pathogens, ____ these extracellular pathogens, and neutralize them by _____ on the pathogen that ______.

Answer 9

antigens, coat, blocking key sites, enhance their infectivity

Question 10

cytotoxic T-cell-mediated approach of _____ that are already ____ to prevent the progression of an ______.

Answer 10

killing cells, infected, established infection

Question 11

The neutralized antibody-coated pathogens can then be ____ by the ____ and eliminated in ____

Answer 11

filtered, spleen, urine or feces

Question 12

Antibodies are _____ proteins produced by ____ that are used by the immune system to ___ and ____ foreign objects, such as ___ and ____.

Answer 12

large, B-cells, identify, neutralize, bacteria, viruses

Question 13

The antibody recognizes a unique part of the foreign target known as an ___

Answer 13

antigen

Question 14

Each tip of the antibody (protein) contains a ____ that is specific for one particular ___ on an antigen (foreign body) –>. analogous to a lock and key

Answer 14

paratope, epitope

Question 15

Using the paratope-epitope binding mechanism, an antibody can _____ a microbe or an infected cell for ___ by the immune system

Answer 15

tag, destruction

Question 16

The Ig monomer of an antibody is a __ -shaped molecule that consists of ___ polypeptide chains: ___ identical ___ chains and __ identical __ chains

Answer 16

Y, 4, 2 heavy, 2 light

Question 17

The ____ region of an antibody determines the class of an immunoglobulin

Answer 17

constant

Question 18

A small region at the tip of the protein is extremely variable, known as the ____ region. Each of these variants can bind to a _____.

Answer 18

hypervariable, different antigen

Question 19

In muscle contraction, ____ filaments bind to ___ filaments in the muscles and as ___ releases a ____ molecule it changes shape moving the ___ filament with it. The ___ filament then returns to its resting position using the ____ of ___.

Answer 19

myosin, actin, myosin, phosphate, actin, myosin, hydrolysis of ATP

Question 20

Kinesins move along microtubule filaments in an ____ direction (___ to ___) to ___ within the cell

Answer 20

anterograde, center to periphery, transport cargo

Question 21

dyneins move along microtubule filaments in a _____ direction (___ to ___) to transport various ____.

Answer 21

retrograde, (periphery to center), cellular cargos

Question 22

Motor proteins aid in movement through ____ ATP hydrolysis that causes _____ in these proteins

Answer 22

exergonic, conformation change

Question 23

Kinesin is present in the cell and helps in the movement of ___ during ___ as well as in the movement of ___ in the cell

Answer 23

chromosomes, cell division, vesicles

Question 24

Dynein helps in the movement of _____ like ___ and ____.

Answer 24

single cell appendages, cilia, flagella