Chapter 3 - Biological Macromolecules Flashcards
(109 cards)
1
Q
4 major biological macromolecule classes
A
Carbohydrates, lipids, proteins, nucleic acids
2
Q
What makes up most of a cells mass?
A
Water
3
Q
What are the building blocks of macromolecules?
A
Monomers are, since macromolecules are polymers themselves
4
Q
When monomers combine with polymers what happens? What is the reaction called?
A
The reaction is called dehydration synthesis, it causes the monomers to release water molecules as byproducts when combining to make polymers
5
Q
What happens with the atoms in a dehydration synthesis reaction?
A
The hydrogen (H+) of one monomer combines with the hydroxyl group (OH-) of another monomer releasing H2O, at the same time the monomers share electrons and form covalent bonds
6
Q
What do dehydration synthesis reactions require to form new bonds
A
Input of energy
7
Q
Glucose monomers can give rise to what molecules?
A
Starch, glycogen, cellulose, …. polymers
8
Q
Polymers break down into monomers during what type of reaction?
A
Hydrolysis
9
Q
Both dehydration synthesis and hydrolysis reactions are catalyzed by what?
A
Enzymes
10
Q
During hydrolysis what happens with the bonds?
A
They break and release energy
11
Q
During hydrolysis the polymer breaks into 2 components; what are they?
A
They are both monomers; one monomer gains a hydrogen (H+) and the other gains (OH-) a hydroxyl group from a split H2O molecule
12
Q
What type of enzymes break down carbohydrates, lipids, and proteins?
Can any enzyme break down them?
A
No, they require specific enzymes to break down each macromolecule
Example: amylase, sucrase, lactase, Maltase, galactase, ect… for carbohydrates
Proteases such as pepsin, peptidases, and hydrochloric acid for proteins
And lipases for lipids
(ALL releasing energy for cellular activity)
13
Q
What is the stoichiometric formula for carbohydrates?
A
(CH2O) ratio of 1:2:1
14
Q
What are the 3 subtypes of carbohydrates?
A
Monosaccharides, disaccharides, and polysaccharides
15
Q
What are simple sugars?
A
Monosaccharides
16
Q
What is the most common monosaccharide?
A
Glucose
17
Q
What is the normal carbon range for simple sugars?
A
3-7
18
Q
Monosaccharides usually end with what suffix
A
-ose
19
Q
What are aldoses?
A
Simple sugars with a CHO functional group (aldehyde group) that is on one end of the molecule
Structure R-CHO
20
Q
What are ketoses?
A
They are simple sugars with a C=O functional group (NOT on the end) forming a ketone functional group
Structure: RC(=O)R
21
Q
Depending on what in the sugar can they be called trioses, pentoses, and hexoses?
A
The number of carbons
22
Q
What is the primary energy producing molecule in humans? What is its chemical formula?
A
Glucose (C6H12O6)
23
Q
During cellular respiration energy releases from glucose helps make what?
A
ATP (adenosine triphosphate)
24
Q
Photosynthesis uses what to produce glucose?
A
CO2, H2O, and light
25
What is similar and different about galactose, fructose and glucose?
They are monosaccharides that all have the same chemical formula (C6H12O6) but differ in structure, this means they are isomers of each other due to different arrangement of functional groups and the asymmetric carbon
26
What is the shape of monosaccharides? What shape are they usually in an aqueous solution?
They can exist as a linear chain or as ring-shaped molecules; in aqueous solution they are usually ring shaped
27
The ring form of glucose can have 2 forms. What are those 2 forms?
if the hydroxyl group is below the number 1 carbon it is the alpha form
If the hydroxyl group is above the number 1 carbon it is the beta form
28
How do disaccharides form? What bond is made?
When 2 monosaccharides undergo a dehydration reaction forming a covalent bond called a glycosidic bond
29
Glycosidic bonds can be what type? What does it depend on?
They can be alpha with the hydroxyl of the number 1 carbon below the ring plane and beta with the hydroxyl above the ring plane
30
Sucrose (table sugar) forms when what happens?
The glycosidic bond is between the number 1 carbon of glucose and the number 2 carbon of fructose
31
Lactose (milk sugar) forms when what reacts?
Glucose and galactose bond (react)
32
Maltose (grain sugar) form when what bonds
2 glucoses bond (react)
33
Depending on what does it decide the Polysaccharide being made?
If they are branched or unbranched, and what monosaccharides they are
34
List some polysaccharides
Starch, glycogen, cellulose, chitin
35
What are the 2 main plant starches?
Amylose (unbranched 1-4 alpha linkages) and amylopectin (branched, 1-4 alpha and 1-6 linkages)
*polysaccharides is how plants store glucose in their roots and seeds
36
What is the point of humans producing salivary amylase?
To break down amylose into smaller molecules like glucose and maltose when it is in the mouth, it then can be absorbed into cells and used
37
Where is glycogen usually found? What is its structure?
It is found in humans and other vertebrates, more specifically it is usually stored in muscles and liver. It is also a highly branched structure
38
What happens when blood glucose levels decrease? What process happens?
Glycogen breaks down to release glucose in a process called glycogenolysis
39
What is the most abundant natural biopolymer?
Cellulose
40
Where is cellulose usually found in nature? And what is special about it’s structure?
It mostly comprises a plants cell wall - it is a beta 1-4 glycosidic polysaccharide which allows the glucose monomers to pack in tightly and form long chains with high rigidity and tensile strength (every other glucose is flipped)
41
Why can humans not digest cellulose?
Because humans don’t have the enzymes necessary to break down beta 1-4 linkages, only few bacteria and protistan species can produce the enzyme cellulase which allows them to break down cellulose into glucose
42
What is chitin? Where is it used? And what is it’s composition?
A polysaccharide found in anthropods and fungi that is composed of N-acetyl-beta-d-glucosamine units (modified sugars), it is also a major component of fungal cell walls
43
What is the cells primary energy source that produces ATP?
Glucose
44
What is cellulose referred to in food?
dietary fiber
45
What are the benefits of fiber? For example that of cellulose
- promoting regular bowel movement by adding bulk
- regulates blood glucose consumption rate
- removes excess cholesterol by binding to cholesterol in the small intestine and prevents particles from entering the blood stream, then exits via feces
- reduces colon cancer
- feeling of fullness
46
What are lipids generally composed of chemically? And general characteristics?
Hydrocarbons with many C-C bonds and C-H bonds. They are insoluble in H2O and hydrophobic. Also generally non-polar
47
What are lipids functions
Insolation , energy reserve, hormones, components of cell membranes
48
What are the types of lipids that we see in life (macromolecules)?
Waxes, oils, phospholipids, and steroids
49
What are fats also called?
Triglycerides or triacylglycerols
50
What are the 2 subunits of lipids? (Describe each chemically)
A glycerol which is an alcohol with 3 carbons, three hydroxyl groups (OH-) and 5 hydrogens.
And a fatty acid which are long hydrocarbon chains with a carboxyl group on one end (COOH-) (most have 12-18 carbons)
51
How does the fatty acid bond to the glycerol?
By bonding to the 3 carbons with an ester bond through an oxygen, releasing H2O (dehydration synthesis)
52
Fatty acids can be what types?
Saturated - max number of hydrogens possible (no double bonds)
Unsaturated - less than the max possible number of hydrogens because they have double bonds
53
Unsaturated fats have a cis confirmation meaning what? What does this cause physically?
A bend forms at the double bond preventing them from packing tightly and keeping them liquid at room temp
54
How is trans fat formed?
By hydrogenating oils to make them more solid-removing the bend by placing hydrogens at the double bonded carbons on opposite sides of (trans conformation)
55
Trans fats lead to what for human health?
Higher LDL (low-density-lipoproteins) leading to plaque formation in arteries and heart disease (why food labels MUST show it)
56
Omega fatty acids are essential fatty acids meaning…
fatty acids they are required by our body but we do not synthesize them
57
What is the chemical composition of omega 3-fatty acids?
They have a double bond between the 3rd and 4th carbon from the hydroxyl end
58
Omega 3-fatty acids have been shown to reduce what in human health?
Sudden death of heart attacks
-lower triglycerides in blood lead to decrease in BP leading to prevention in thrombosis by inhibiting blood clotting
59
Waxes chemical composition
Long chain esterified alcohols found in bird preen glands and on plant surfaces
60
Phospholipids are a major component of what?
Plasma membranes
61
Phospholipids are composed of what? (2 parts)
2 fatty acids attached to a glycerol forming a diacylglycerol
A phosphate group occupies the space where the 3rd fatty acid would be in a triglyceride
62
Phospholipids are amphipathic meaning what?
They have a hydrophobic part (the fatty acid tails) and a hydrophilic part (the head - phosphate and glycerol)
63
What ways do the hydrophilic and hydrophobic parts face?
Hydrophilic head faces out towards the water while the hydrophobic tails face each other
64
Steroids common chemical characteristics
Have a fused ring structure and are hydrophobic (insoluble in water)
-they have 4 linked carbon rings, some have short tail and some have hydroxyl groups making them sterol alcohols
65
Where does cholesterol come from in the human body and what is it a precursor of (list a few)?
Cholesterol is synthesized in the human liver and is a precursor of hormones such as testosterone and estradiol as well as vitamin D and bile salts, also components of plasma membranes
66
All proteins are polymers of what?
Amino acids
67
Each enzyme has a specific reactant on which the enzyme acts in called…
The substrate
68
Enzymes that break down their reactants are called what? While those that build complex products are called what?
Break down - catabolic enzymes
Build up - anabolic enzymes
69
What are hormones (simply put)
Chemical signaling molecules
70
Most hormones are proteins but there are also some that are…
Steroids
71
What are the proteins 5 main functions
Transport, structural, defense, contractile, and storage
72
Proteins shape determines its function but it can be permanently altered by changing its shape usually through pH or temperature, what is this change in the shape called?
Denaturation
73
What is the chemical composition of each amino acid
Each amino acid has a central carbon bonded to an amino functional group (NH2-) on one side, a carboxyl functional group (COOH-) on one side, a hydrogen on the third side, and a variable side chain denoted as the R group on the 4th side. It is the change in the R group that codes for different amino acids
74
How many amino acids are there and how much are essential for human function?
20 - 9 of which are essential
75
What are the 5 overarching categories of amino acids?
-Non polar
-Polar
-Positively charged
-Negatively charged
-Non polar, aromatic
76
A simple polymer of amino acids are called polypeptides - each polypeptide has what on the ends (chemically)?
A free amino group on one end called the N terminal and a free carboxyl group on the other end called the C terminal
77
The primary structure of a protein is what?
A proteins amino acid sequence
78
Adding the wrong amino acid in the chain during DNA polymerization would alter the proteins function. How does that work in the often seen case of sickle cell anemia?
Changing a glutamate to a valine in hemoglobin causes sickle cell anemia which is 1 in 600 amino acids or 1 in 1800 nucleotide base pairs. All it takes.
79
What is the secondary structure of a protein?
The regular arrangement of the polypeptide chains. They usually take one of 2 shapes
Alpha helixes
Or
Beta pleated sheets
80
How do the R-groups protrude in both the alpha helical and beta pleated sheets structure?
The R-group protrudes out from the alpha helical chain while the R-group protrudes out above and below in the B pleated sheet
81
What is the tertiary structure of a protein?
The three dimensional structure
82
How does the 3D structure form?
-The interactions between the R-groups
-ionic bonds, disulfide linkages, and hydrogen bonds all contribute to the proteins 3D shape
-non polar R-groups lie in the proteins interior while the polar R-groups lie to the outside further contributing to the proteins 3D shape
83
What is a proteins Quaternary structure?
The formation of several polypeptide chains
84
How can the denaturation of a protein be reversible?
Because the polypeptides primary structure is conserved, it can regain its shape and function once the denaturing agent is removed
But it also can be irreversible ex. frying an egg
85
What do chaperonins (a class of proteins called chaperone proteins) help with?
The folding process, they associate with the target protein during the folding process, once target protein is folded they dissociate from the protein
86
What are the nucleic acids?
DNA (deoxyribonucleic acid) and RNA (ribonucleic acid)
87
What is DNA?
The genetic material of an organism (contains genes which code for an organisms traits)
88
Where is DNA found in eukaryotes?
The nucleus, and in the chloroplast and mitochondria
89
All of an organisms DNA is its…
Genome
90
What does DNA bind with to make chromosomes in eukaryotic organisms?
Histone proteins
91
What nucleic acid is involved in protein synthesis?
RNA
92
Does DNA leave the nucleus in translation?
No, DNA does not leave the nucleus, instead mRNA leaves and communicates the code to the ribosomes to direct the production of the proteins
93
What are the types of RNA?
mRNA (messenger RNA), tRNA (transfer RNA), and rRNA (ribosmal RNA)
94
DNA and RNA are polymers composed of what monomers?
Nucleotides (monomers that make up the DNA molecule, which is a polynucleotide)
95
What are the 3 parts to a nucleotide?
-the nitrogenous base (Adenine, thymine, guanine, cytosine)
-a pentose sugar (a ribose sugar which is a five carbon sugar)
-a phosphate group
96
Main Example of a non polar amino acid?
Glycine (Gly)
97
What is the R-group in the amino acid Glycine?
-H
98
What is the main example of a polar amino acid?
Serine(Ser)
99
What is the R-group for serine?
-CH2-OH
100
What is the main example of a positively charged amino acid?
Lysine (Lys)
101
What is the R-group for Lysine?
-CH2-CH2-CH2-CH2-NH3
102
What is the main example of a negatively charged amino acid?
Aspartate (Asp)
103
What is the R-group for Aspartate?
-CH2-COO
104
What is an example of a non-polar, aromatic amino acid?
Tyrosine (Tyr)
105
What is the R-group for tyrosine?
CH2-(ring with 3 double bonds)-OH
106
What does calmodulin store in the body and where?
It stores calcium ions in smooth muscle
107
Sucrose is commonly known as
Table sugar
108
Ribose and fructose form rings when?
When in water (solution)
109
How many oxygen molecules can hemoglobin carry? And where on the molecule?
4, and on the corners
