enzymes and homeostasis

Question 1

_______ glands secrete hormones directly into the blood

Answer 1

endocrine

Question 2

_______ glands secrete hormones into ducts

Answer 2

exocrine

Question 3

the protein portion of an enzyme is called the ______

Answer 3

apoenzyme

Question 4

the model that considers the substrate and active site to be a perfect fit for each other

Answer 4

lock and key

Question 5

this enlargement of the throat can occur due to either hypothyroidism OR hyperthyroidism

Answer 5

goiter

Question 6

maintaining the internal environment of the body at equilibrium

Answer 6

homeostasis

Question 7

insulin is an example of a ______ hormone

Answer 7

peptide

Question 8

every enzyme has an optimal ____ at which it will work in the body. The exact value of this will depend upon where in the body that enzyme is functioning. Values too far above OR below optimal will result in the denaturation of the enzyme

Answer 8

pH

Question 9

a factor affecting the rate of a chemical reaction

Answer 9

temperature

Question 10

organic, but non-protein cofactors are often derived from these substances

Answer 10

vitamins

Question 11

in order to cool your body, blood vessels near the surface of the skin will ______

Answer 11

dilate

Question 12

many ______ are inhibitors that permanently bind to the active site of enzymes, rendering them inactive

Answer 12

poisons

Question 13

an ______ occurs to correct the situation when a receptor detects that conditions in the body are out of the normal range

Answer 13

adaptive response

Question 14

all enzymes names end in this suffix

Answer 14

ase (sometimes “in”)

Question 15

enzyme activity can be greatly reduced when temperatures get too _____. this situation is irreversible

Answer 15

hot

Question 16

components of the body which detect light

Answer 16

photoreceptors

Question 17

increasing this factor will increase the rate of a chemical reaction

Answer 17

surface area

Question 18

all of the body’s sensory receptors are connected to the ________ system

Answer 18

nervous

Question 19

the portion of an enzyme that binds with the substrate

Answer 19

active site

Question 20

cofactors can belong to this group of substances

Answer 20

metals

Question 21

components of the body which detect chemical changes

Answer 21

chemoreceptors

Question 22

a ______ increases the rate of a chemical reaction by lowering the activation energy

Answer 22

catalyst

Question 23

when the product of an enzyme catalyzed reaction binds to the ______ site on the enzyme, it causes a change to the shape of the active site and the enzyme becomes temporarily inactive

Answer 23

allosteric

Question 24

this word is what happens to a protein when its shape is changed by being exposed to heat or certain chemicals

Answer 24

denature

Question 25

_______ like mercury and lead can cause the denaturation of enzymes

Answer 25

heavy metals

Question 26

_______ are chemical messengers which help cells communicate with each other

Answer 26

hormones

Question 27

an organic, but non-protein substance (eg. vitamin) which place a role in forming a functioning enzyme

Answer 27

coenzyme

Question 28

this word refers to the combination of all the chemical reactions that are occurring within an organism

Answer 28

metabolism

Question 29

components of the body which detect changes in blood pressure

Answer 29

baroreceptors (pressoreceptors)

Question 30

the idea that the active site modifies its shape as it forms the enzyme-substrate complex

Answer 30

induced fit

Question 31

the receptors for regulating body temperature are located in this part of the brain

Answer 31

hypothalamus

Question 32

the enzyme maltase decomposes the sugar ______

Answer 32

maltose

Question 33

the _____ energy is the amount of energy that is required to get a chemical reaction started

Answer 33

activation

Question 34

a solution with a higher _______ will provide a faster reaction rate than a solution with one that is lower

Answer 34

concentration

Question 35

________ feedback systems are very rare in humans, but are present in situations like childbirth and breastfeeding

Answer 35

positive

Question 36

enzyme activity can be reduced when temperatures become too _____, however this situation can be reversed

Answer 36

cold

Question 37

this enzyme catalyzes the decomposition of hydrogen peroxide

Answer 37

catalase

Question 38

this element is required for the production of thyroxin

Answer 38

iodine

Question 39

if your body temperature drops below normal, your brain may direct your body to start involuntary muscle contractions which makes you start to _______

Answer 39

shiver

Question 40

blood pressure, blood pH, and blood glucose levels are all part of _______ feedback systems where the correction of the level which is out of range leads to a SLOWING or CEASING of the corrective measure

Answer 40

negative

Question 41

in order to function properly, enzymes require an additional substance called a _______, which are typically inorganic ions of metals

Answer 41

cofactor

Question 42

components of the body which detect temperature changes

Answer 42

thermoreceptors

Question 43

the term metabolic ______ refers to a sequence of enzyme-catalyzed chemical reactions which are all linked to each other

Answer 43

pathway

Question 44

metabolic rate is controlled by the hormone thyroxin which is produced by the _____ gland

Answer 44

thyroid

Question 45

a word used to describe a substance which will combine with the active site of an enzyme during a reaction

Answer 45

substrate

Question 46

enzymes are said to be ______ because each enzyme catalyzes only one type of reaction

Answer 46

specific

Question 47

in an enzyme catalyzed reaction, reaction rate will continue to increase with the addition of more substrate until all enzyme active sites are ______. the addition of more substrate beyond this point will result in no increase in reaction rate

Answer 47

saturated

Question 48

lipid based hormones are composed of ______

Answer 48

steroids

Question 49

a biological catalyst is called a(n) _______

Answer 49

enzyme

Question 50

_______ hormones act inside of the nucleus by binding to sites on the DNA.

Answer 50

steroid

Question 51

_______ hormones cannot pass through the cell membrane and must bind with a receptor on the cell's surface.

Answer 51

peptide

Question 52

describe the role of enzymes in a metabolic pathway

Answer 52

- it is a sequence of enzyme-catalyzed chemical reactions which are all linked to each other - they begin with a particular reactant and terminate with an end product - each enzyme controls one reaction only; therefore it is specific for that reaction

Question 53

what is the difference between lock & key and induced fit?

Answer 53

lock and key= enzyme has a specific shape which allows the substrate to fit (ex. you can't use your house key to open your car door) induced fit= some active sites undergo a slight change in shape in order to accommodate a substrate

Question 54

how does negative feedback inhibition affect a enzyme catalyzed reaction?

Answer 54

it occurs when the end product of a reaction interferes with the enzyme that helped produce it. (binds to allosteric site) Therefore, the enzyme changes shape and can't catalyze the reaction anymore.

Question 55

what's the difference between a catalyst and an enzyme?

Answer 55

- Catalysts are substances that increase or decrease the rate of a chemical reaction. - Enzymes are biological catalysts, which speed up reactions in living things

Question 56

what are the 4 ways of increasing the rate of a chemical reaction?

Answer 56

surface area, temperature, concentration, and using a catalyst

Question 57

what is the name for the functional enzyme?

Answer 57

holoenzyme

Question 58

Describe positive feedback systems

Answer 58

Childbirth and breastfeeding are examples of positive feedback systems. During contractions, the hormone oxytocin continues to be made so that the contractions become closer together. This is the opposite of negative feedback systems where result of a reaction is reduced to bring the system back to a stable state

Question 59

Do enzymes change after a reaction?

Answer 59

no

Question 60

why is homeostasis important?

Answer 60

it maintains the optimal conditions for enzyme activity throughout the body as well as proper cell function

Question 61

what is significant about the allosteric site?

Answer 61

it controls the amount of products being produced (can increase or decrease)

Question 62

what would make an enzyme graph go down?

Answer 62

it was denatured or an inhibitor was present

Question 63

Why is thyroxine important?

Answer 63

it is the main hormone secreted into our blood and plays vital roles in digestion, heart and muscle function, brain development. Too much or too little thyroxine can cause hyperthyroidism or hypothyroidism

Question 64

What part of the graph do you choose if a question asks you about reaction rate?

Answer 64

Pick the high point of the graph

Question 65

What part of the graph do you choose if a question asks you about the time for a certain amount of product?

Answer 65

Pick the low point of the graph

Question 66

what is another word for metabolic rate?

Answer 66

resting rate

Question 67

what are two things your cells use up when idling (resting)?

Answer 67

oxygen and glucose

Question 68

difference between a fast & slow metabolic rate

Answer 68

fast rate = more oxygen and glucose | slow rate = less oxygen and glucose

Question 69

what is the pituitary gland?

Answer 69

it works with the hypothalamus and plays a major role in regulating vital body functions

Question 70

How could you tell the difference between a steroid or a protein going into a cell?

Answer 70

- if it is a steroid it would go straight through to the nucleus because it is lipid-based and easily goes through the cell membrane - if it is a protein it would have to bind to a receptor

Question 71

what is something that binds permanently to an enzyme?

Answer 71

poison

Question 72

What does cyanide stop the pathway of?

Answer 72

ATP