Lecture 10 Flashcards
1
Q
What are enzymes?
A
Enzymes are proteins that act as natural catalysts in biochemical reactions.
2
Q
What are the two types of biochemical reactions?
A
Anabolic and catabolic.
3
Q
What are reactants?
A
Molecules that are meant to react with each other in a solution.
4
Q
What do enzymes do?
A
They help reactants meet each other and speed up biochemical reactions.
5
Q
What is a catalyst?
A
An agent that speeds up a chemical reaction without participating in it.
6
Q
What is the active site of an enzyme?
A
The location where a reaction happens.
7
Q
What is the binding site of an enzyme?
A
The location where substrates attach to the enzyme.
8
Q
What is an enzyme-substrate complex?
A
The entire unit formed when substrates are in the enzyme’s binding site.
9
Q
What is a conformational change in enzymes?
A
A slight change in the enzyme’s shape when substrates are bound.
10
Q
What are substrates?
A
The reactants that are helped by an enzyme.
11
Q
What happens to substrates at the active site?
A
They react to form or break covalent bonds.
12
Q
What is the difference between reversible and irreversible reactions?
A
Reversible reactions can go both ways, while irreversible reactions can only go one way.
13
Q
Which suffix do most enzyme names end with?
A
-ase.
14
Q
What are coenzymes and cofactors?
A
Helpers that assist enzymes during biochemical reactions.
15
Q
What are typical examples of cofactors?
A
Minerals such as Cu, Zn, Ca, Mn, Mg.
micronutrients
The human body recycles and reuses these over and over again.
16
Q
What are typical examples of coenzymes?
A
Vitamins such as Folate, Vitamin B1, B2, B3, Ascorbic acid, Biotin.
micronutrients
The human body recycles and reuses these over and over again.
17
Q
What is denaturation?
A
An irreversible change in the 3-D shape of a protein, leading to loss of function.
18
Q
What factors can denature an enzyme?
A
- Extreme pH
- High temperature
- High pressure
- Physical stress
- High concentration of ions
19
Q
What is the optimal temperature for human enzymes?
A
37°C.
20
Q
What does the pH scale measure?
A
The acidity or alkalinity of a solution.
21
Q
What is a neutral pH?
A
A pH of 7, which is neither acidic nor alkaline.
22
Q
What pH value indicates a strong acid?
A
Closer to 0 on the pH scale.
23
Q
What pH value indicates a strong base?
A
Closer to 14 on the pH scale.
24
Q
Which enzyme is activated by hydrochloric acid in the stomach?
A
Pepsin.
25
True or False: Most enzymes prefer a neutral pH.
True.
26
Fill in the blank: The change in shape of an enzyme upon substrate binding is called _______.
[conformational change]
27
What happens to enzymes when they are denatured?
They are destroyed or lose their functional shape
## Footnote
Denaturation can be caused by extreme pH, temperature, or other environmental factors.
28
Which enzyme is activated by hydrochloric acid in the stomach?
Pepsin
## Footnote
Pepsin is a proteolytic enzyme that functions optimally in acidic conditions.
29
What is the pH level of the small intestine?
Right above 8
## Footnote
Sodium bicarbonate is released in the small intestine, creating an alkaline environment.
30
What is the normal pH range of human blood?
7.35 to 7.45
## Footnote
A drop below 7.35 indicates acidosis.
31
What does enzyme inhibition mean?
To stop or slow down enzyme activity
## Footnote
This does not include factors like temperature or pH that denature enzymes.
32
List the three types of enzyme inhibition.
* Competitive inhibition
* Non-competitive inhibition
* Feedback inhibition
33
What is feedback inhibition?
A process that prevents overproduction by inhibiting an enzyme through its accumulated product
## Footnote
It functions like a stop signal when too much product accumulates.
34
Describe competitive inhibition.
A molecule temporarily occupies the binding site of the enzyme
## Footnote
Example: Aspirin inhibits Cyclooxygenase (COX) to reduce inflammation.
35
What distinguishes non-competitive inhibition from competitive inhibition?
Non-competitive inhibitors bind to a different site on the enzyme, causing a permanent conformational change
## Footnote
Example: Carbon monoxide
permanently occupies the hemoglobin molecule, making it permanently unavailable to carry oxygen or CO2.
36
What are the two main divisions of the nervous system?
* Central Nervous System (CNS)
* Peripheral Nervous System (PNS)
37
What comprises the Central Nervous System?
The Brain and the Spinal Cord
38
List the four major parts of the brain.
* Cerebrum (higher brain)
* Diencephalon (interbrain)
* Brainstem (lower brain)
* Cerebellum (hindbrain)
39
What are the three parts of the brainstem?
* Medulla Oblongata
* Pons
* Midbrain
40
What functions does the Medulla Oblongata control?
* Vasomotor center
* Respiratory control
* Cough reflex
* Vomit reflex
## Footnote
Bottom of brainstem
41
Which cranial nerves originate from the Medulla Oblongata?
* IX (9)
* X (10)
* XI (11)
* XII (12)
42
What is the primary role of the Hypothalamus?
Homeostatic control and communication between the CNS and the Endocrine system
## Footnote
It connects to the Pituitary gland.
43
What are the functions of the Cerebellum?
* Coordination of skeletal muscle contractions
* Awareness of body position & movement direction
* Maintenance of posture & balance
44
What is the outer layer of the cerebrum called?
Cerebral Cortex
## Footnote
It is composed of gray matter and contains folds called gyri.
45
What are the four lobes of the cerebral cortex?
* Frontal Lobe
* Parietal Lobe
* Temporal Lobe
* Occipital Lobe
46
What is the function of the Frontal Lobe?
Primary motor area, reasoning, problem solving, and oral/written speech
47
What is Wernicke's area responsible for?
Native speech comprehension and foreign language comprehension
## Footnote
Located in the left temporal lobe.
48
What neurotransmitter is associated with pleasure and reward?
Dopamine
49
Which neurotransmitter is involved in producing calm and peace?
Serotonin
50
What effect does GABA have on brain activity?
Suppresses neuron activity and slows down Action Potential
51
Fill in the blank: The largest part of the brain responsible for conscious thought is the _______.
Cerebrum
52
Which part of the brain controls the cough reflex?
Medulla Oblongata
53
How are the right and left cerebral hemispheres separated?
By the Longitudinal fissure
54
What is the primary function of the Parietal Lobe?
Primary sensory area
55
Which lobe is responsible for visual processing?
Occipital Lobe
56
What does BMI stand for?
Body Mass Index
57
What is the formula for calculating BMI?
BMI = (mass in kg) / height in meters²
58
What does a BMI between 20 and 25 indicate?
Healthy weight
59
What BMI value is considered underweight?
Under 20
60
What BMI value indicates severe malnourishment or underweight?
Under 16
61
What BMI range is classified as overweight?
25-30
62
What BMI range is considered obese?
30-35
63
What is classified as morbid obesity in terms of BMI?
Any BMI over 35
64
Why might a bodybuilder have a high BMI?
Due to high muscle mass
65
What is one limitation of BMI as a health assessment tool?
It does not reflect body composition (% body fat vs. % lean body mass)
66
List some chronic diseases associated with high BMI.
* Hypertension
* Heart disease
* Diabetes
67
What parameters do doctors consider when calculating BMI?
Weight and height
68
Fill in the blank: The BMI is calculated by dividing the mass in kg by the height in _______.
meters²
69
What do health insurance companies use BMI for?
Assessing health risks
70
solvent
the base for the solution
71
solutes
suspended or dissolved in this solution
72
Factors That Influence Enzymatic Activity:
1. Concentration of Substrates: The higher the concentration of substrates, the faster the reaction will move forward (until substrates and products reach equilibrium).
2. Concentration of Coenzymes/Cofactors (if they are necessary): A higher concentration of coenzymes/cofactors will cause the reaction to move forward and go faster.
3. Temperature: A lower temperature will result in molecules moving slower = a slower reaction. A higher temperature will result in the molecules moving faster = a faster reaction.
4. pH of the Solution
73
Which of the following is NOT true about the pH scale?
a. The solution that has a high concentration of hydrogen protons will have a high pH number
b. The solution that has a low concentration of hydrogen protons is considered alkaline
c. Acid is a substance that increases the hydrogen proton concentration in a solution
d. A base is a substance that has a high pH number
| A
74
Cranial Nerve X (10) or ____ is a major parasympathetic nerve; it is the only cranial nerve innervating visceral organs.
Vagus Nerve
75
Cranial Nerve XI (11) or ____ innervates structures of the neck.
accessory nerve
76
Functions of the Pons
∙ Controls some respiratory reflexes and facial nerves
∙ Origin of 4 cranial nerves: V (5), VI (6), VII (7), VIII (8).
∙ Controls some auditory reflexes, such as turning toward a source of a sound.
## Footnote
Middle of brainstem
77
Functions of the Midbrain
∙ Center of eye reflexes
∙ Origin for cranial nerves III and IV (both control movement of eye muscles)
∙ Conducts impulses between the medulla oblongata and cerebellum, and between the spinal cord and diencephalon
78
The Diencephalon is the next level up from the Brainstem and it consists of 2 parts: Thalamus and ____
hypothalamus
79
The hypothalamus connects to the ____ (the Master gland), which rules most other glands and tells them what to do.
Pituitary gland
80
The Hypothalamus controls the following functions of the body:
∙ body temperature
∙ hydration
∙ electrolyte balance
∙ nutritional balance
∙ sleep-awake cycle
∙ reproduction
∙ both Sympathetic and Parasympathetic divisions of NS
81
Thalamus
collects sensory impulses coming from the spinal cord and directs them to the appropriate parts of the Primary Sensory Area (PSA) in the cerebrum, the higher brain.
| It is sort of like a receptionist.
82
The Cerebellum is divided into 2 hemispheres separated by the ____
Vermis
83
The surface of the cerebral cortex consists of multiple folds called ____, with indentations between the folds called ____.
Gyri
Sulci
84
The Cerebral Pre-cortex, or Sub-cortex includes the Limbic System consisting of:
Hippocampus, Amygdala,
Reticular Activating System (RAS)
85
Responsible for learning and memory formation
Hippocampus
86
Responsible for emotions and emotional responses (incl. fears)
Amygdala
87
Responsible for
wakefulness, alertness, and ability to focus
Reticular Activating System
(RAS)
88
The ____ separates the frontal lobe from the parietal lobe
Central Sulcus
89
The ____ is a special structure at the bottom of the longitudinal fissure. It facilitates communication between the right and left hemispheres, so that the right side of the brain knows what is going on in the left brain, and vice versa.
Corpus callosum
90
Auditory and olfactory functions are processed by the
temporal lobe
91
Stimulates brain activity, focuses the brain, and produces a sense of alertness.
Adrenaline
92
Slow down brain activity and reduce perception of pain.
Endorphins
93
Used by sympathetic neurons for communication with visceral organs.
Epinephrine (Adrenaline)
94
Used in somatic neurons and for communication with skeletal muscles; also used by Parasympathetic neurons for communication with Visceral organs.
Acetylcholine
