L2. Chemical components of a cell Flashcards

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

what are the four types of macromolecules

A
  • polysaccharides, glycogen, and starch (in plants)
  • fats and membrane lipids
  • proteins
  • nucleic acids
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

macromolecules - polysaccharides, glycogen, and starch (in plants)

A

made up of sugars

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

macromolecules - fats and membrane lipids

A

made of fatty acids

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

macromolecules - proteins

A

made of amino acids

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

macromolecules - nucleic acids

A

made of nucleotides

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

define nucleotides

A

the building blocks of nucleic acids (DNA, RNA)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

nucleotides - explain their functions

A
  • genetic code (DNA, RNA)
  • energy carriers
  • co-enzymes
  • cell signaling
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

nucleotides: genetic code - difference between DNA and RNA

A
  • DNA: Deoxyribonucleic Acid, missing one hydroxyl group in 2 position
  • RNA: Ribonucleic Acid, hydroxyl group in 2 position
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

nucleotides: genetic code - similarities between DNA and RNA

A
  • Sugar backbone
  • Nitrogenous base
  • Phosphates
  • phosphodiester bonds
  • Synthesis always happens 5’ → 3’
  • Base pairing of complementary strand creates the protein
  • 1 start codon and 3 stop codon
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

nucleotides: genetic code - Phosphates

A
  • they are hydrolyzed by the hydroxyl group
  • this gives energy to drive the growing RNA or DNA strand
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

nucleotides: genetic code - phosphodiester bonds

A
  • how nucleotides are joined together
  • the bonds are between 5’ and 3’ carbon atoms on the sugar via a phosphate group
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

nucleotides: genetic code - why must synthesis happen from 5’ -> 3’

A
  • 3’ hydroxyl is important for creating phosphodiester bond
  • Without it, you cannot add a growing nucleotide
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

nucleotides: genetic code - explain the functions of RNA

A
  1. transcribe the genetic code
  2. translate the genetic code: tRNA
  3. structural - ribosomal RNA
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

nucleotides - energy carriers

A
  • nucleotides carry chemical energy in their easily hydrolyzed phosphoanhydride bonds
  • when you break the phosphoanhyride bonds, it creates a lot of energy and enzymes can use the energy to create work
  • Ex: ATP
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

nucleotides: energy carriers - ATP

A
  • it is a phosphorylated nucleotide
  • consists of a ribose sugar
  • consists of a hydroxyl group
  • it is a ribonucleotide
  • serves as the energy currency of the cell
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

nucleotides: energy carriers - what makes dATP different than ATP

A
  • it is a nucleotide used to synthesize DNA
  • consists of a deoxyribose sugar
  • consists of a hydrogen
  • it is a deoxyribonucleotide
  • serves as a precursor for DNA synthesis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

nucleotides - coenzymes

A
  • nucleotides can combine with enzymes to form coenzymes
  • they usher reactions
  • ex: coenzyme A (CoA)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

nucleotide: coenzymes - CoA

A

Nucleotide derivative that is used to facilitate catabolic reactions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

nucleotide - signaling

A
  • nucleotides can be used as signaling molecules in the cell
  • cyclic AMP: facilitates signals more quickly
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

nucleotides - how do different cells express different genes

A
  • each cell have a specific coordinated expression of genes that need to be turned on
  • resulting in different cells having different genes turned on and expressed
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

amino acids - explain the general formula

A
  • R side chain
  • amino group
  • alpha-carbon atom
  • carboxyl group
  • it is read from N-C terminus
22
Q

amino acids - R side chain

A
  • it is what makes each amino acid unique
  • each R group is different and the order in a particular sequence of a protein will determine the protein’s function
23
Q

amino acids - explain their cellular roles

A
  • protein synthesis
  • neurotransmitters (GABA, Glutamate)
  • precursors to other molecules
  • metabolites (serotonin, melatonin)
24
Q

amino acids - making proteins

A
  • DNA is transcribed into mRNA
  • mRNA is translated into amino acids
  • each codon (3 base pairs) corresponds to one amino acid
  • amino acids form polypeptide chains
  • polypeptide chains fold into proteins
25
Q

amino acids: making proteins - peptide bonds

A
  • they are formed when two proteins have combined
  • a water molecule is kicked off when the bond is formed
  • the peptide bond is stiff and is formed around the C-N bond
26
Q

amino acids: making proteins - tripeptide

A

these are non-peptide bonds that are flexible rather than stiff

27
Q

amino acids - what are the essential amino acids

A
  • they are 11
  • we get it from food
28
Q

amino acids - what are the non-essential amino acids

A
  • they are 9
  • our bodies can produce it
29
Q

carbohydrates - what are monosaccharides

A
  • simple sugars
  • formula: (CH2O)n
  • n = 3, 4, 5, or 6
  • ex: glucose or ribose
30
Q

carbohydrates - what are disaccharides

A

sucrose = glucose + frutose

31
Q

carbohydrates - what are olygosaccharides

A

2-10 monomers

32
Q

carbohydrates - what are polysaccharides

A

100s - 1000s subunits

33
Q

carbohydrates - explain the cellular roles

A
  • energy source
  • mechanical source (cellulose, chitin)
  • glycoproteins and glycolipids have many functions
34
Q

carbohydrates: cellular roles - energy source

A
  • quick use (glucose)
  • long term storage (glycogen, starch)
35
Q

carbohydrates: cellular roles - glycoproteins and glycolipids

A
  • intracellular signaling
  • cell surface receptor interactions
  • adhesion
  • protein interactions
36
Q

carbohydrates - explain glycosidic bonds

A
  • these bonds make disaccharides
  • can be formed through condensation (water expelled) or hydrolysis (water consumed)
  • a proteins function can be determined based on how a protein is glycosylated (via adding vs losing a sugar)
37
Q

carbohydrates: energy storage - starch

A
  • simple polysaccharide
  • plant cells
  • polymer and long-term storage of glucose
38
Q

carbohydrates: energy storage - what is glucose

A

an energy source and reserve for cells

39
Q

carbohydrates: energy storage - what is glycogen

A
  • in animal cells
  • polymer and long-term store of glucose
  • as its sugars get broken down, the sugars are fed into the mitochondria to make ATP
40
Q

carbohydrates: mechanical support - what is cellulose

A
  • in plant cells, within the cell wall
  • polymer of glucose
  • linear
41
Q

carbohydrates: mechanical support - what is chitin

A
  • in insect exoskeleton and fungal cell wall
  • linear polymer of GlcNAc, which is a derivative of glucose
42
Q

carbohydrates - what are complex oligosaccharides

A
  • these are linked to proteins or lipids
  • they are proteins that have a sugar sequence that is non-repetitive
  • this can then change the function of the protein
  • can facilitate new interactions between proteins
43
Q

lipids and phospholipids

A
  • make up cell membranes
  • ex: fatty acids
44
Q

lipids and phospholipids - fatty acids

A
  • behaves as an acid
  • reactive
  • covalent linkage to other molecules
  • hydrophilic carboxylic acid head (outside the head)
  • hydrophobic hydrocarbon tail (inside cell)
  • whole molecule is called amphipathic
45
Q

lipids and phospholipids - saturated vs unsaturated fatty acids

A
  • saturated: all spaces are filled with hydrogen and makes the membrane more stiff
  • unsaturated: some spaces are not filled with hydrogen, this then forms double bonds creating a kink. This makes to membrane more flexible
46
Q

lipids and phospholipids - lipid aggregates

A
  • lipid aggregates form a bubble in contact with water due to their amphipathic properties
  • when washing your hands, the soap forms aggregates and the germs fall on the outside of the aggregate. This then allows them to be washed off with water
47
Q

lipids and phospholipids - what are phospholipids

A
  • they have a hydrophilic head (outside cell) and a hydrophobic fatty acid tail (inside cell)
  • this forms the lipid bilayer
48
Q

lipids and phospholipids - glycolipids

A
  • they are lipids with a sugar head group
  • important for: membrane stability, cell-cell interactions, anchor for proteins, and cell signal transduction
49
Q

lipids and phospholipids - triacylglycerols

A
  • they form large spherical fat droplets in the cell cytoplasm
  • they are insoluble in water but soluble in fat and organic solvents
  • they serve as concentrated food reserves
50
Q

lipids and phospholipids: triacylglycerols - where are they found

A
  • in animals: fats
  • in plants: oils
51
Q

lipids and phospholipids - fatty acid derivatives

A
  • composed of aromatic rings
  • maintains membrane fluidity
  • ex: steroids and hormones
52
Q

lipids and phospholipids: fatty acid derivatives - steroids

A
  • cholesterol
  • prevents membranes from being too fluid as temperature gets too hot