Chap. 3: Medical Biochemistry

Question 1

4 main macromolecules:

Answer 1

1. carbohydrates
2. lipids
3. proteins
4. nucleic acids

Question 2

Carbohydrates (state the monomer, polymer, and function)

Answer 2

• Monomer: monosaccharide
• Polymer: polysaccharide
• Function: the body’s primary source of energy, including energy production and energy storage

Question 3

What carbohydrate does the body use as the primary source of energy?

Answer 3

glucose

Question 4

How does the body store carbohydrates as?

Answer 4

the polymer: glycogen

Question 5

How does the body deal with excess carbohydrates/glucose?

Answer 5

it either stores it as fat or excretes it as waste

Question 6

What biochemistry process does the body use carbohydrates for?

Answer 6

cellular respiration

Question 7

Lipids (state the monomer, examples, and function)

Answer 7

• Monomer: 1 glycerol and 3 fatty acids
• Examples: fats, waxes, sterols
• Functions: short-term energy, insulating and protecting, and structure (phospholipid bilayer)

Question 8

phospholipids

Answer 8

• it is a main component of the cell membrane. to make up the cell membrane, it is in companion with proteins embedded into it
• semi-permeable

Question 9

diffusion

Answer 9

net movement of molecules from a region of higher concentration to lower concentration

diffusion moves from high -> low

Question 10

osmosis

Answer 10

movement of water from a region of higher concentration to a lower concentration

diffusion of water from high -> low

Question 11

hypotonic

Answer 11

• when compared, the concentration of solute is less
• there is a lower concentration of solute outside the cell, meaning that there is a high concentration of water outside the cell as well, which also means that there is a low concentration of water inside the cell. so by the laws of osmosis, water flows into the cell, causing it to swell
• cell swells
• outside < inside (less concentration of solute outside)
• if you want water to enter a dehydrated cell, you would submerge the cell into a hypotonic solution
• water goes into cell

Question 12

isotonic

Answer 12

• when compared, the concentration of solute is equal/same
• cell is good
• outside = inside (concentration of solute is equal outside and inside the cell)

Question 13

hypertonic

Answer 13

• when compared, the concentration of solute is high
• there is a higher concentration of solute outside the cell, meaning that there is a lower concentration of water outside the cell as well, which also means that there is a high concentration of water inside the cell. so by the laws of osmosis, water flows out of the cell, causing it to shrivel
• cell shrivel
• outside > inside (higher concentration of solute outside)
• if you want water to leave a swelled cell, you would submerge the cell into a hypertonic solution
• water goes out of cell

Question 14

What is the cell membrane composed of?

Answer 14

phospholipid bilayer and proteins

Question 15

Why is the phospholipid bilayer semi-permeable?

Answer 15

because it lets some things in and other things not

Question 16

What 3 things can pass through the cell membrane without help?

Answer 16

water, carbon dioxide, and oxygen
H2O, CO2, O2

Question 17

Proteins (state the monomer, polymer, and function)

Answer 17

• Monomer: amino acid
• Polypeptide: polypeptide/ protein
• Function: help fight disease, control rates of reaction (enzymes), help move things in and out of the cell (structural component)

Question 18

Enzymes (state the properties and why you need them)

Answer 18

• Properties: it’s specific (lock and key theory), it will increase the rate of reactions, it is unchanged at the end of a reaction
• Why you need them: reactions are too slow to maintain life so these enzymes help speed those reactions up

Question 19

Denaturation

Answer 19

denaturation happens in enzymes. it is the disruption of the 3D shape of the enzyme causing the breakage of weak bonds and the function of the enzyme is destroyed
- Causes for denaturation: unfitting pH level or temperature for the enzyme

Question 20

Where are proteins made?

Answer 20

in the ribosomes

Question 21

Lock and Key Theory

Answer 21

• a theory applying to enzymes.
• both enzymes and substrates have specific complementary geometric shapes. so that makes them fit into each other and the function of the enzyme is performed.
• enzymes are very specific

Question 22

What are the components involved in the lock and key theory?

Answer 22

the enzyme, substrate, product, and active site

Question 23

Nucleic acids (state the monomer, polymer, and function)

Answer 23

• Monomer: nucleotide
• Polymer: DNA or RNA
• Function: holds and carries genetic information

Question 24

What are the four base nucleotides in DNA?

Answer 24

Adenine-Thymine
Guanine-Cytosine

Question 25

What are the four base nucleotides in RNA?

Answer 25

Adenine-Uracil
Guanine-Cytosine

Question 26

Human genome

Answer 26

the human genome is the entire set of DNA instructions found in a cell
- it has 3 billion bases and around 20,000 genes
- these genes code for specific traits and they make proteins

Question 27

Epigenome

Answer 27

all the modifications that regulate the activity (expression) of the genes.
EX: some epigenetic changes increase your cancer risk. For instance, having a mutation in the BRCA1 gene that prevents it from working properly makes you more likely to get breast and other cancers.

Question 28

Adenosine Triphosphate (ATP) (state the definition and structure)

Answer 28

the source of energy for use and storage at the cellular level
- Structure: nucleoside triphosphate - nitrogenous base (adenine), a ribose sugar, and three serially bonded phosphate groups
- it’s continuously recycled in the body

Question 29

Central Dogma

Answer 29

a theory stating that genetic information flows only in one direction, from DNA, to RNA, to protein, or RNA directly to protein. consists of replication, transcription, and translation

DNA -> RNA -> Protein

Question 30

What is the monomer of nucleic acid?

Answer 30

nucleotides

Question 31

Where in the cell can we find DNA?

Answer 31

nucleus