Exam 1 Lec 1 Biological Molecules Flashcards
0
Q
Mass
A
The measure of the quantity of matter present
1
Q
All matters are composed of ________.
A
atoms
2
Q
Atomic number is determined by the number of _________.
A
protons
3
Q
Isotopes
A
Same element has same number of protons but different number of neutrons.
4
Q
Radioisotopes
A
Unstable and spontaneously give off energy in the form of radiation from the atomic nucleus
5
Q
Radioactive decay
A
Release of energy transforms the original atom
6
Q
Valence shell
A
Outermost electron shell
7
Q
Covalent bond
A
Sharing pair(s) of electrons between atoms
8
Q
Compound
A
Pure substance made up of 2 or more elements bonded together in a fixed ratio
9
Q
Eletronegativity
A
The attractive force that an atomic nucleus exerts on electrons in a covalent bond
10
Q
Ionic bond
A
Electrical attraction between oppositely charged ions
11
Q
Complex ions
A
Groups of covalently bonded atoms that carry an electric charge
12
Q
Hydrogen bond
A
Attraction between hydrogen attached to an electronegative atom and the electronegative atom of another molecule
13
Q
Ver der Waals force
A
Interaction between non-polar substances; occur when atoms of two molecules are in close proximity
14
Q
Energy
A
Capacity to do work; in chemical context, capacity to change
15
Q
Solute
A
The substance dissolved
16
Q
Solvent
A
The liquid
17
Q
Buffer
A
Maintains internal constancy
18
Q
Amphipathic
A
Both hydrophobic and hydrophilic
19
Q
Levels of organization (6)
A
atoms > cells > tissues > organs > systems > organism
20
Q
4 types of biological molecules
A
proteins/ carbohydrates/ nucleic acids/ lipids
21
Q
Proteins are made up of _________________.
A
amino acids
22
Q
List 3 monosaccharides:
A
Glucose, fructose, and galactose
23
Q
Nucleic acids are made up of _________________.
A
nucleotides
24
Lipids are made up of ________ and ___________.
Glycerol and fatty acids
25
The atomic number and mass number of an element is?
The atomic number is the number of proton present in that element. It is unique for every single element. The mass number is the total number of protons and neutrons in a nucleus.
26
The reaction HCl -> H+ + Cl- in the human stomach is an example of?
Formation of ions by dissolving an acid
27
Oxygen is a(n) ________, while the oxygen we breathe (O2) is a(n) _________, and the carbon dioxide we exhale is a(n) ___________.
Element; compound; compound.
28
When electrons are shared equally between atoms they form what bond?
Covalent bond
29
What are the properties of water?
- ice floats (atoms are apart apart, less dense then liquid water)
- melting, freezing, and heat capacity
- cohesion and surface tension
- as solvent
30
What is a hydrophilic body fluid?
"Water-loving"; polar
31
Polar substances are hydrophobic. (T/F)
F
32
A hydrogen bond involving only parts of the backbone is a single strand of protein would be considered part of what type of protein strucutre?
Primary; peptide bond
33
The most abundant molecule in the cell is?
Water (H2O)
34
What causes the amphipathic nature of phospholipids?
Because it has a hydrophilic head and a hydrophobic tail.
35
What would be the complementary sequence to this strand of DNA: GATTACA?
CTAATGT
36
What type of molecules are the most diverse in terms of structure and types of roles on the cells?
Proteins
37
Why are steroids classified as lipids?
Steroids are lipids because they are hydrophobic and insoluble in water, but they do not resemble lipids since they have a structure composed of four fused rings.
38
Why are enzymes always proteins in living organisms?
Because there are high diversity of proteins. Proteins can change shape. Those proteins that can facilitate/catalyze reactions are enzymes.
39
What is a nucleotide in DNA made of?
A nitrogen-containing base, a pentose sugar (deoxyribose), and one to three phosphate groups.
40
What are the four bases found in DNA?
Adenine (A), Cytosine (C), Guanine (G), Thymine (T)
41
How does RNA differ from DNA? (structurally/chemically)
RNA is composed of ribose, whereas DNA is composed of deoxyribose. Uracil (U) is a base only for RNA, whereas thymine (T) is a base only for DNA.
DNA encodes heredity information. RNA expresses the heredity information.
42
What is the "RNA world" hypothesis?
The RNA world hypothesis proposes that self-replicating ribonucleic acid (RNA) molecules were precursors to all current life on Earth.
43
What is an enzyme?
An enzyme is a protein molecule that can catalyze chemical reactions in the cell. Substrate binds to an enzyme, and is released as a product. Enzyme can catalyze both anabolic reaction and catabolic reaction.
44
What are the building blocks of nucleic acids?
Nucleotides
45
How is molecular information expressed in an organism?
Genetic information is stored in DNA. DNA is transcribed into RNA, which then future translates into a protein.
46
Why is using heat to speed up biological reactions problematic?
Because enzymes and other proteins are sensitive to temperature. When they are in very hot environment that they cannot withstand, they will denature, and will no longer be functionable.
47
2 forms of base of nucleic acid, which contains a single ring, and which contains a fused double-ring?
Pyrimidines (single ring), and purines (fused double-ring)
48
Name purines:
Adenine (A), and Guanine (G)
49
Name pyrimidines:
Uracil (U), Thymine (T), and Cytosine (C)
51
Primary structure of protein:
- Amino acid monomers are joined, forming polypeptides chains
- Repeating units
- Typical condensation reactions form those peptide bonds between amino acids
52
Secondary structure of protein:
- Polypeptide chains may form alpha-helices or beta-pleated sheets
- Hydrogen bonds form between different amino acids
- R group extends outward
53
Tertiary structure of protein:
- Polypeptides fold, forming specific shapes. Folds are stabilized by bonds, including hydrogen bonds, and disulfide bridges
- R groups interaction
- Hydrophobic interactions
- Hydrogen, covalent, and ionic bonds can also be formed
- Starts to see 3-dimensional shape
53
9 systems of human body
1. Nervous
2. Endocrine
3. Lymphatic/ Immune
4. Digestive
5. Cardiovascular
6. Urinary
7. Reproductive
8. Muscular
9. Respiratory
54
Quaternary structure of protein:
- Two or more polypeptides assemble to form larger protein molecules
- Usually large in size, and complex
55
Nervous system
- Fast acting control system
| - Responds to internal and external changes
56
Muscular system
- Locomotion
- Facial Expression
- Maintains posture
- Generates heat
- Allows manipulation of environment
57
Endocrine system
Glands secretes hormones that regulate:
- Growth
- Reproduction
- Nutrient use
58
Cardiovascular system
- Blood vessels transport blood
- carries oxygen and carbon dioxide
- carries wastes and nutrients
- Heart pumps blood
59
Lymphatic/ Immune system
- Picks up fluid leaked from red blood cells
- Carries white blood cells
- Mounts attack against foreign substances
60
Respiratory system
- Keeps body supplied with oxygen
- Removes carbon dioxide
- Gaseous exchange occur through the wall of air sacs in the lungs
61
Digestive system
- Breaks down food into absorbable units
| - Undigestible food are excreted as feces
62
Urinary system
- Eliminate nitrogenous wastes
| - Regulates water, electrolyte, and acid-base balance
63
Reproductive system
- To produce offspring
- Male reproductive system
- testes produce sperms and male sex hormones
- Female reproductive system
- ovaries produces eggs and female sex hormones
- mammary glands produce milk
64
List 4 chemical bonds
- Covalent
- Ionic
- Hydrogen
- Van der Waals
65
List 4 major biomolecules
- proteins
- carbohydrates
- nucleic acids
- lipids
66
Which biomolecule is not considered as macromolecule? Why?
Lipids; because it is not large enough
67
Difference between marcomolecules (proteins, carbohydrates, and nucleic acid) and lipids?
The first three are hydrophilic, and the last is hydrophobic.
68
Which biological molecule has the largest composition of total biological molecules?
Proteins, followed by nucleic acids, carbohydrates, and lipids
69
How many different amino acids are there?
20
70
Difference between lipid and phospholipid?
Lipid has one glycerol and three fatty acids, whereas phospholipid has one glycerol, two fatty acids, and two more groups in the head region.
71
Functions of biological molecules are related to:
Their shapes and chemical properties
72
Condensation:
- Anabolic
- Release of water molecules
- Monomers -> Polymers
- Aka dehydration
- When you want to store stuffs
73
Hydrolysis:
- Catabolic
- Gain of water molecules
- Polymers -> Monomers
74
Most diverse biological molecule is ____________.
Proteins
75
___________ is crucial to the function of a protein and is influenced largely by the _____________ of amino acids.
Folding; sequence
76
Amino acid structure
- Center carbon
- R side chain
- Carboxyl group
- Amino group
- Hydrogen atom
77
What determines the hydrophilicity and hydrophobicity of an amino acid?
Hydrophobicity and hydrophilicity of the R group attached
78
Side chains can also be ____________.
Electrically charged
79
Essential amino acid
Cannot generate by our own body, need to obtain from diet
80
Essential amino acid can be converted to non-essential amino acid by _____________________.
Trans-amination
81
Give 3 examples of essential amino acids:
Leucine, lysine, valine, etc.
82
Amino acids polymerization
- Condensation
- Release of water molecule
- Peptide bond are formed between amino acids (from one N-terminus to the C-terminus of another)
83
Name of 4 protein structure levels
- Primary
- Secondary
- Tertiary
- Quaternary
84
Enzymes
Need certain surface shapes in order to bind with substrate correctly
85
Carrier proteins
In the cell surface membrane, it allows substances to enter the cell
86
Chemical signals
- For example, hormones
| - Binds to proteins on the cell surface membrane
87
pH maintained by the _________ system.
Urinary
88
Native protein
Functional proteins, opposite to denatured proteins
89
Carbohydrate functions:
- Energy storage
| - Structural componenets
90
4 major categories of carbohydrates:
- Monosaccharide
- Disaccharide
- Oligosaccharide (3-20)
- Polysaccharide (>20)
91
Carbohydrate polymerization
- Condensation of two glucose, alpha linkage forms
92
What do we call the covalent bond in carbohydrate:
Glycosidic linkage
93
Carbohydrate polymers:
- Starch
- Amylose (branched)
- Amylopectin (unbranched)
- Glycogen
94
Glucose polymers branch ones that are more accessible to the cells because it is __________________________.
Easier to break
95
Structural component
- Cellulose
| - Chitin
96
What is chitin?
Chemically modified sugar
97
Nucleic acids
- Polymers that are specialized for storage and transmission of information
- DNA and RNA
- Polymer of nucleotides
- DNA encodes heredity information; RNA transfers the information; information in RNA decoded to specify the sequence of amino acids in proteins
98
Structure of nucleotide
Phosphate group, sugar, and base
99
Difference between deoxyribose and ribose
Deoxyribose has a H in 2' C, instead of an OH group
100
RNA is _________ stranded
single
101
Phosphodiester linkages
A phosphodiester bond occurs when exactly two of the hydroxyl groups in phosphoric acid react with hydroxyl groups on other molecules to form two ester bonds.
102
The Central Dogma
DNA -> RNA -> Proteins
103
List all the electrically charged hydrophilic amino acids
- Arginine
- Histidine
- Lysine
- Aspartic acid
- Glutamic acid
104
List all uncharged, polar hydrophilic amino acid
- Serinine
- Threonine
- Asparagine
- Glutamine
- Tyrosine
105
List all special case amino acid
- Cysteine
- Glycine
- Proline
106
List all hydrophobic amino acid
- Alanine
- Isoleucine
- Leucine
- Methionine
- Pheylalanine
- Tryptophan
- Valine
107
List all essential amino acids
- Histidine
- Lysine
- Threonine
- Isoleucine
- Leucine
- Methionine
- Phenylalaniine
- Tryptophan
- Valine
108
What does a branched polymer indicate?
It indicates that there are side chain substituted to the long chain
109
Which polymer is easier to break, branched or unbranched?
Branched
110
How is chitin generated?
By adding a nitrogen group; chitin is a form of glucose
111
Use of chitin, give 2 examples:
- Exoskeleton of anthropods
| - Surgical threads, bio-degradable
112
List 3 ribonucleotides
- ATP
- GTP
- cAMP
113
ATP as:
energy transducers in many biochemical reactions
114
GTP is used to
synthesize proteins
115
cAMP is essential for:
hormone actions, and transferring of information by the nervous system
116
Structure of ATP:
Adenosine, ribose, three phosphate group (high energy stored between the linkages)
117
Lipids are attached to each other via ___________________.
Van der Waals force
118
Lipids functions: (6)
- Thermal insulation
- Capture of light energy (carotenoid)
- Cell membrane (phospholipid)
- Electrical insulation of nerves (myolin)
- Energy storage (triglycerides)
- Hormones and vitamins (steroids and modified fatty acid)
119
Fatty acid is ___________.
hydrocarbon chain
120
Linkage between fatty acids and glycerol in lipids in called:
ester linkage
121
2 types of lipids:
Saturated and unsaturated
122
Saturated fats has double bonds. (T/F)
F; Unsaturated fats do
123
Is unsaturated or saturated fat liquid in room temperature? Explain.
Unsaturated. Because there is double bond(s) in unsaturated fat, its surface area is decreased, double bonds do not allow the fat to solidify
124
Phospholipid structure
Hydrophilic: choline, phosphate, and glycerol
Hydrophobic: two fatty acid tails
125
In the phospholipid bilayer, which region of the phospholipid is facing out?
Hydrophilic heads
