biochemistry - topic 1 Flashcards
1
Q
Anabolic
A
- a reaction that uses dehydration synthesis to build polymers from smaller molecules
- requires energy (product)
2
Q
Catabolic
A
- uses hydrolysis to break down large chemical molecules into smaller ones
- produces energy (reactant)
3
Q
Polymer
A
- a molecule composed of three or more sub-units
4
Q
Dehydration synthesis
A
- smaller molecules formed into larger molecules by the removal of water
5
Q
Hydrolysis
A
- larger molecules broken down into smaller molecules by the addition of water
6
Q
Metabolism
A
- the chemical reactions that occur inside an organism’s cells
7
Q
Carbohydrates
A
- the human body’s most important source of energy
- when unused, it is turned into fat for long-term storage (and a second energy source)
- made of carbon, hydrogen, and oxygen
8
Q
Monosaccharides
A
- a single sugar unit
9
Q
Glucose
A
- blood sugar
- used for energy in cellular respiration
10
Q
Fructose
A
- honey and fruit sugars
- sweetest out of the monosaccharides
11
Q
Galactose
A
- milk sugars
- antigens
12
Q
Antigens
A
- a substance (usually protein) that stimulates an antibody
- immune responses
13
Q
Isomer
A
- a group of chemicals that have the same chemical formula but are built differently
14
Q
Disaccharides
A
- a sugar formed by two monosaccharides
15
Q
Sucrose
A
- glucose + fructose
- sweetest of the disaccharides
16
Q
Maltose
A
- glucose + glucose
- grains and seed sugars
- broken down starches found in animal enzymes
17
Q
Lactose
A
- glucose + galactose
- milk sugar
18
Q
Polysaccharides
A
- a carbohydrate made up of sub-units of monosaccharides through dehydration synthesis
19
Q
Starch
A
- plant carbohydrate that stores energy
20
Q
Glycogen
A
- animal carbohydrate that stores energy
- more useful energy because there are more branches of starch = more surface area for enzymes
21
Q
Cellulose
A
- plant carbohydrate that makes up the cell wall
- fibre
22
Q
3 reasons why we need fibre
A
- prevents constipation
- prevents colon and rectum cancer
- lowers blood cholesterol
23
Q
Lipids
A
- a group of organic compounds that cannot dissolve in water
24
Q
Two main functions of lipids
A
- Energy storage
- Structural material
25
Structural functions of lipids
- help in making cell membranes
- surround nerve fibres
- protect organs
- form some hormones
- vitamin carrier
- insulation (ex. blubber)
- form waxes = waterproof (ex. birds)
25
Triglycerides
- a lipid that is made out of glycerol and three fatty acids through dehydration synthesis
- fats
26
Unsaturated fatty acids
- liquid at room temperature
- plant-based oils
- one or more double bonds
27
Saturated fatty acids
- solid at room temperature
- animal-based fats
have no double bonds; each carbon is surrounded by hydrogens (hydrogenation)
28
Phospholipids
- a major component of the cell membrane that has a phosphate molecule attached to a glycerol backbone
- hydrophilic head and hydrophobic tail which allows it to form bilayer membranes
29
Steroids
- a range of molecules with a common structure of four fused carbon rings
- provides building material for hormones, bile, etc.
--> ex. cholesterol
30
Proteins
- a chain of amino acids that form the structural parts of cells or act as antibodies or enzymes
- made of carbon, hydrogen, oxygen, and nitrogen
- the shape of a protein determines its function
31
Amino acids
- a chemical that contains nitrogen and can link together to create proteins through dehydration synthesis
- 20 amino acids (monomers); 8 are plant-based essentials
- Each has 3 parts
1. amino group
2. carboxyl group
3. R group
32
Peptide bond
- a bond that links amino acids together
- A sequence of them is called a polypeptide
33
Functions of proteins
- (structural) proteins are used in making different organelles and cells:
- hormones, antibodies, hair/nail tissue, mitochondria, enzymes, hemoglobin (red blood cells)
- Can be used as an energy source but only as a last resort because it can be infectious to the liver
34
Structure of proteins
- Primary: Amino acids in a linear arrangement
- Secondary: Folds/coils due to hydrogen bonding
- Tertiary: R group interactions cause more folding
- Quaternary: 2+ proteins folding together
35
Denaturation
- a temporary change in a protein's shape physically or chemically (pH, radiation, heat, etc.)
36
Coagulation
- a permanent change in a protein's shape
37
Enzymes
- a protein catalyst that allows chemical reactions to occur more readily at lower temperatures
- generally end in "-ase" (ex. amylase, lactase, lipase)
- form temporary chemical bonds with the substrate that are going through a reaction
38
Active site
- the region of the enzyme where the substrate bonds
39
Substrate
- a molecule in which an enzyme works
40
Enzyme substrate complex
- where the substrate molecules bond to an enzyme's active site
41
Coenzyme
- organic molecules synthesized from vitamins that help enzymes combine with a substrate molecule
42
Cofactor
- organic ions that help enzymes combine with a substrate molecule
43
Optimal temperature for enzymes
35-40°C
- an increase in temperature will increase collisions and movement of molecules and vice versa
- enzymes denature at a higher temp
44
Optimal pH for enzymes
pH 6 and pH 8
- anything above or below the optimum may cause a change in the enzyme's shape
45
Concentration
- the greater number of substrate molecules = greater number of collisions and rate of reaction
46
Competitive inhibitors
- interferes with an enzyme's active site so the substrate cannot bind
- As long as it remains attached to the active site, the enzyme cannot catalyze its normal reaction
47
Negative feedback/feedback inhibition
- blocking an enzyme in a metabolic process by the route's end product until it is used up
48
HDL
good cholesterol
high density lipoprotein
49
LDL
bad cholesterol
low density lipoprotein
