Exam 2 Flashcards
(103 cards)
1
Q
What is a nucleic acid made of? give an example
A
a phosphate group, sugar, nitrogenous base ; ATP, DNA, RNA
2
Q
Explain endosymbiotic theory
A
Theory that mitochondria and chloroplasts were once independent bacteria cells but formed a symbiotic relationship with another cell to create a eukaryotic cell
3
Q
What property of carbon makes it so versatile? And why?
A
It has four unpaired electrons so it is able to create 4 bonds
4
Q
Explain the order of the secretory pathway
A
- Protein is put into RER as ribosome makes it
- Vesicle buds off RER with protein cargo and delivers it to Golgi where the proteins are modified
- Vesicle buds off Golgi with protein cargo
- Vesicle fuses to plasma membrane, Secreted proteins are released by exocytosis, Membrane bound proteins become part of the cell membrane
5
Q
The breakdown of complex molecules into simpler compounds, releasing energy
A
Catabolic pathway
6
Q
Gangliosides (lipids found in membrane neurons) are most likely produced in which organelle?
A
Smooth er (where lipids are produced)
7
Q
Name of the thing that walks along the cytoskeleton tracks to transport vesicles
A
Proteins
8
Q
The removal of –H and –OH from monomers to join the monomers into a polymer and form water
A
Dehydration synthesis
9
Q
Name 3 properties of water
A
Surface tension, capillary action, cohesion, adhesion, expansion upon freezing, solvent properties, heat capacity
10
Q
What is the central carbon of a protein surrounded by
A
Hydrogen, amino group, carboxyl group, R group
11
Q
Name the bond type: unequal sharing of electrons between covalently bonded oxygen (or N or F) and hydrogen atoms
A
Hydrogen bonds
12
Q
Name the 3 types of gated channels
A
Ligand, voltage, and mechanical
13
Q
Reaction where the transfer of energy is due to the loss of an electron
A
Oxidation
14
Q
What happens to a cell that is put in a hypotonic solution
A
The cell swells, water moves into the cell
15
Q
What is the number of neutrons of chlorine if the atomic mass is 36 (the atomic number=17)
A
19
16
Q
Reaction that is not spontaneous and requires energy
A
Endergonic reaction
17
Q
Define “amphipathic” and give an example
A
A molecule with a polar and nonpolar end, phospholipids
18
Q
Function of ribosomes
A
Synthesizes proteins
19
Q
Compare and contrast passive and active transport
A
-Both require a channel protein
-Active transport requires ATP
20
Q
Cells where you can find a cell wall
A
Plant cells and prokaryotic cells
21
Q
The twisting of the string of amino acids into an alpha-helix or pleated sheet
A
Secondary structure of a protein
22
Q
What is the property of an acidic vs basic solution
A
Acids have a higher H+ concentrations and bases have higher –OH concentration
23
Q
Name the enzyme: attaches to an allosteric site, changing the shape of the active site
A
Noncompetitive inhibitor
24
Q
Function of cholesterol in the plasma membrane
A
To keep the plasma membrane from becoming too fluid or too stiff (maintains fluidity)
25
The mechanism by which enzymes work
Lowering activation energy
26
How many protons does oxygen (O) have?
atomic mass: 16 atomic number: 8
8
27
How many neutrons does phosphorus (P) have?
atomic mass: 31 atomic number: 15
16
28
compared to an acidic solution at pH 5, a basic solution at pH 8 has...
1,000 times fewer hydrogen ions (10x10x10, fewer as you go up the scale)
29
If you were a fish in a pond in the winter in Minnesota, for what property of water would you be most grateful?
hydrogen bonding
30
sugars are soluble in water because they...
are polar molecules
31
digestible carbohydrate in your diet could come from which of the following:
- glycogen
- starch
- cellulose
- sucrose
- starch and sucrose
starch and sucrose
32
amino acid side chains in the interior of a cytoplasmic protein will typically be...
nonpolar
33
the proper shape of a protein is...
-determined by the sequence of its amino acids
- called its conformation
- required for the protein to function
- held together by bonding interactions between the amino acid side chains
34
if you heat a cell to a moderately higher temperature than it is normally used to, which molecule will stop working first?
protein
35
which structure is common to all three domains of life?
phospholipid bilayer cell membrane
36
the enzyme hexosaminidase normally breaks down excess or damaged gangliosides (lipids found in the membranes of neurons). Which organelle is hexosaminidase found in?
lysosomes
37
at low tide the scuds and plants are in a hypotonic solution, what will happen to the water around them
enter their cells by osmosis
38
the plant can adapt to a hypotonic solution because its cell wall...
prevents the cell membrane from swelling until it bursts
39
How does a transport vesicle move from the cell body to the nerve terminal?
along the cytoskeleton using motor proteins
40
How can a protein channel be regulated?
-binding of a ligand
-voltage change
-mechanical stress
-endocytosis of carrier
41
how do we release energy from bonds in a carbohydrate?
oxidation
42
What is OILRIG?
Oxidation Is Loss, Reduction Is Gain (of electrons)
43
What does LEO says GER mean?
Loss of Electron is Oxidation, Gain of Electron is Reduction
44
What charge do electrons have?
negative
45
What charge do neutrons have?
neutral/no charge
46
what charge do protons have?
positive
47
What is a covalent bond?
when two or more atoms share electrons
48
What is an ionic bond?
the attraction between oppositely fully charged atoms (ions) ; transfer of electrons from one to another atom forming ions ; gain or lose an electron
49
What is a hydrogen bond?
the partial positive hydrogen atom in one polar covalent molecule will be attracted to an electronegative atom in another polar covalent molecule ; opposite charges attract ; partially charged groups
50
Describe a Polar bond
- possess regions of positive and negative charge
- electrons are not shared equally between two atoms
- can have regions of partial charge created by covalent bond
- can have fully charged regions created by ionization
51
describe a nonpolar bond
- electrons are shared equally between two atoms
- charge is evenly distributed
52
How do you tell if a bond is polar?
- O and N are electronegative and don't share well
- c-o bond is on the outside
- the molecule is charged
- look at the differences in electronegativity between the two atoms (0.4 to 1.7 = polar)
53
How can you tell if a bond is nonpolar?
- some atoms share equally
- C and H share well
- C-C or C-H are nonpolar
54
Define Hydrophobic
water fearing ; non polar non ionic substances
55
Define hydrophilic
water liking ; polar molecules because they can H-bond with water; soluble in water
56
What are functional groups
chemical groups attached to the carbon skeleton that participates in chemical reactions ; atoms or clusters of atoms that are covalently bonded to carbon backbone
57
What are the common functional groups
- hydroxyl group -OH
- carbonyl group -CHO or =CO
- carboxyl group -COOH or -COO-
- amino group -NH2 or -NH3+
- sulfhydryl group -SH
- methyl group - CHHH
- phosphate group - P or -OPO23
58
Describe the Dehydration Reaction
- dehydration removes a water molecule, forming a new bond
59
Describe Hydrolysis
breaking down a polymer ; hydrolysis adds a water molecule, breaking a bond
60
what are the sub units of carbohydrates
monosaccharides
61
what are the sub units of nucleic acids
nucleotides (building blocks of DNA and RNA)
62
what are the sub units of lipids
fatty acids and glycerol
63
what are the sub units of proteins
amino acids
64
what are the polar regions of the macromolecules
carbohydrates - hydroxyl groups (-OH)
nucleic acids - phosphate groups and sugar molecules
lipids - phosphate head and glycerol in phospholipids
proteins - parts that have polar amino acid side chains
65
what are the non polar regions of the macromolecules
carbohydrates - methyl groups or hydrocarbon chains
nucleic acids - nitrogen bases
lipids - fatty acid tails
proteins - hydrophobic amino acids
66
describe the structure of a phospholipid
have a polar head (phosphate group, hydrophilic) and a nonpolar tail (fatty acids, hydrophobic)
67
what is the purpose of triglycerides
energy storage (class of lipids ; saturated and unsaturated fats and oils)
68
describe when a lipid is saturated
no double bonds between carbons
69
describe when a lipid is unsaturated
one or more double bonds
70
describe the role of proteins
used to build repair, and run everything (antibody, enzyme, messenger, structural , transport, storage)
71
describe how a protein is synthesized from amino acids
1) a carboxyl group of one amino acid is positioned next to the amino group of another amino acid
2) dehydration reaction forms a peptide bond
3) many amino acids linked by peptide bods then form polypeptides
4) the sequence of amino acids determines the 3D shape which determines function
5) when the polypeptide twists and folds (due to R group interaction) it forms a protein
72
Describe Eukaryotic cells
-DNA in the nucleus
- protists, fungi, animals, plants
- contain membrane bound organelles
- have a nucleus
73
Describe prokaryotic cells
- domains bacteria and archaea
- DNA is in the nucleoid region
- smaller in size compared to eukaryotic
- no membrane bound organelles in the cytoplasm
- has a cell wall
74
What do plant cells have that animal cells don't?
a cell wall
75
what is the purpose of the plasma membrane (aka cell membrane)
- acts as a boundary separating the interior of the cell w/ its external environment
- regulates substance entry and exit
- allows cell to receive and respond to singles
- cell recognition , cell adhesion, molecular transport, and regulation of internal environment
76
describe the purpose of a cell wall and where they can be found
- found in prokaryotic and plant cells
- structural support, protection, water intake regulation through osmosis, cell growth, and communication
77
what cell organelle is a surface structure that gives shape, support, and protection to plants
cell wall
78
what cell organelle is the control center of the cell and directs all the cells activities which also being involved in cell division
nucleus
79
what cell organelle releases energy for cell functions and is the site of ATP production
mitochondria
80
what cell organelle are factories for building proteins
ribosomes
81
what cell organelle are roadways for moving materials throughout the cell
cytoskeleton
82
what cell organelle manufactures ribosome parts (proteins and RNA)
nucleolus
83
what cell organelle is semi fluid material inside a living cell in which the other cell organelles are suspended
cytoplasm
84
what cell organelle contains digestive enzymes
lysosomes
85
what cell organelle encloses the cell's genetic material
nuclear membrane
86
what cell organelle is the storehouse for excess water, food, waste, etc.
vacuoles
87
what cell organelle is a green organelle of a plant cell where photosynthesis takes place
chloroplasts
88
what cell organelle modifies, packages, and sorts proteins for transport out of the cell
Golgi
89
what cell organelle is strands within the nucleus which form chromosomes
chromatin
90
what cell organelle holds the contents of the cell together
cell membrane
91
what cell organelle is hereditary material that carries the genetic code
DNA
92
what cell organelle detoxifies drugs and poisons
Smooth ER
93
what cell organelle folds proteins
rough ER
94
what cell organelles synthesizes membranes ; compartmentalizes the cell to keep proteins formed in the rough ER separate from those of free ribosomes
endoplasmic reticulum
95
Define Osmosis
the movement of water across a semi permeable membrane from high to low concentration
96
what does the atomic number of an atom represent
number of protons
97
what does the atomic mass represent in an atom
the sum of protons + neutrons
98
what is the strongest and weakest bond
strongest - covalent ( share pair of electrons )
weakest - hydrogen bonds ( attraction between 2 polar groups)
99
what is cohesion
water property that water adheres to itself
100
what is adhesion
water property that water adheres to other polar things
101
what are the main factors of water's properties
- molecular shape
- polarity and ability to form hydrogen bonds
102
what does it mean that phospholipids are amphipathic
they have both polar heads and non polar tails
103
what drives the formation of membranes
H bonds between phospholipids and water
