Biochemistry Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

What is an aqueous solution?

A

All solutions where water is a solvent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How is water a polar molecule?

A

The covalent bonds between the oxygen and the two hydrogens bond in a way so that the hydrogens are not as far apart from each other as possible. The hydrogens are relatively close together and this causes the side with the hydrogens to obtain a positive charge. The opposite side (with the oxygen) will then result in becoming negatively charged

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is cohesion?

A

-Molecules of the same type are attracted to each other
-The positive side of one oxygen molecule is attracted to the negative side of another oxygen molecule (this is a hydrogen bond)
EXAMPLES:
-water droplets
-surface tension (insects)
-able to move as a water “column” in vascular tissues of plants

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is adhesion?

A

Attraction between two unlike molecules. Hydrogen bonds cause water molecules to be attracted to cellulose molecules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is one example of cohesion and adhesion working together?

A

The column of water in plants.

The column is pulled up by cohesion and adhesion keeps the water from falling down again

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How are water’s thermal properties important?

A
  • Water has a high specific heat meaning that water can absorb or give off a lot of heat without changing it’s temperature too much this causes the temperature to be quite stable
  • Another property is high heat of vaporization, water absorbs a lot of heat when it evaporates, good for cooling mechanism
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What kind of molecules can water dissolve?

A

Water is a good solvent for other polar molecules including carbohydrates, proteins and nucleic acids (DNA and RNA)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

List some properties of water

A

-Polar molecule
-Able to form hydrogen bonds
^Cohesion
^Adhesion
-Good solvent
-High specific heat
-High evaporation temperature
-Good for transport

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is a different name for polar molecules (referring to as to whether or not the substance can be dissolved in water)?

A

Hydrophilic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Give an example of a hydrophilic substance

A

Carbohydrates

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Give an example of a hydrophobic substance

A

Long chains of hydrocarbons => fatty acids in triglyceride lipids and phospholipids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the monomers of carbohydrates?

A

Monosaccharides

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How do monosaccharides form larger sugars?

A

Two glucose molecules undergo a condensation reaction resulting in a water molecule and a maltose molecule where the glucose molecules have joined by a 1-4 glycosidic bond

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are some examples of carbohydrates?

A
Monosaccharides:
-glucose
-fructose
-galactose
Disaccharides:
-maltose
-sucrose
-lactose
Polysaccharides:
-cellulose
-starch
-glycogen
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Why do plants need cellulose?

A
  • Major component of cell wall

- Rigidity/support to stems, leaves

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are two energy storages?

A

Plants: starch (amylose (linear, no side branches) and amylopectin)
People: glycogen (in the liver)

17
Q

What do all fatty acids have in common?

A

A methyl group on one end (CH3) and a carboxyl group (COOH) on the other end

18
Q

Where can you find saturated fatty acids?

A

Butter, bacon, fat in red meat

19
Q

Where can you find polyunsaturated fatty acids?

A

Olive oil

20
Q

What is the difference between cis- and trans- fatty acids?

A

Cis fatty acids have not been straightened out in processing while trans fatty acids have been processed and straightened out and (partly) hydrogenated

21
Q

What is an example of a cis fatty acid?

A

Omega-3

22
Q

What are triglycerides?

A

The most common lipid in plants and animals. They consist of a glycerol molecule as well as three fatty acid tails

23
Q

How are triglycerides formed?

A

A condensation reaction occurs and the fatty acids bond to the glycerol with an ester bond

24
Q

Why are carbohydrates important to humans?

A

Energy

25
Q

Why are lipids important to humans?

A
  • Energy storage
  • Heat insulation
  • Membranes
  • Hormones
26
Q

Why are proteins important?

A

WE ARE PROTEINS

  • Enzymes
  • DNA
27
Q

What are the monomers of proteins?

A

Amino acids

28
Q

What “groups” make up the amino acid?

A

The amine group, the carboxyl group and the R group

29
Q

What are some examples of proteins?

A
  • Insulin (protein hormone produced by pancreas results in decrease of blood sugar levels and increase of sugar inside cells)
  • Immunoglobulin (antibody that recognizes antigens as part of the immune system)
  • Collagen (main protein component of connective tissue, skin, tendons, ligaments)
30
Q

What are the levels of organization in proteins?

A
  1. sequence of amino acids decides 3D shape
  2. repetitive shapes of a helix or a pleated sheet
  3. globular, bumpy?
  4. many polypeptide chains
31
Q

What is the difference between polypeptides and proteins?

A

Proteins are always ready to carry out its function, polypeptides, not always they have to combine with other polypeptides first

32
Q

What can happen to a protein if the temperature in the environment changes?

A

It can become denatured, it can lose its 3D shape because the hydrogen bonds that form the spirals (helix) are quite weak and they break when there’s out stress (temperature change) on them.

33
Q

What can happen to a protein if the pH in the environment changes?

A

The protein can denature, when the environment has a lot of for example H+ ions, they will prevent hydrogen bonding from happening and the protein might be permanently changed

34
Q

When does an enzyme start working?

A

When a substrate binds to the active site

35
Q

How do enzymes speed up reaction?

A

They lower the energy needed in order for the reaction to occur; they lower the activation energy

36
Q

When is a solution acidic and when is it alkaline?

A

Acidic-many hydrogen ions (H+)

Alkaline-many hydroxide ions (-OH)

37
Q

Give an example of a use of enzymes in an industry

A
  • Detergent for washing clothes

- Lactose reduced milk