Chapter 4-7 Biology Flashcards
(197 cards)
1
Q
Nucleic acid monomers
A
Nucleic acids are made up of nucleotides
DNA has deoxyribonucleotides
RNA has ribonucleotides
2
Q
Nucleic acid polymers?
A
DNA and RNA are both nucleic acid polymers
DNA= deoxyribonucleic acid
RNA= ribonucleic acid
3
Q
Primary structure of DNA
A
Linear sequence of nucleotides/nitrogenous bases (ATGC) linked together via phosphodiester bonds
4
Q
Secondary structure of DNA
A
Double- helix, hydrogen bonding between the bases, antiparallel strands
5
Q
Tertiary structure of DNA
A
Supercoils, wrapping around histones
6
Q
What are all the bases of DNA and how do they pair?
A
Adenine - Thymine
Guanine - Cytosine
7
Q
What are all the bases of RNA and how do they pair?
A
Adenine - Uracil
Guanine - Cytosine
8
Q
Which bases are pyrimidines and which ones are purines? (Remember shorter name longer structure)
A
Pyrimidines: cytosine, uracil, and thymine
Purines: guanine, adenine
9
Q
4 differences between DNA and RNA
A
- The sugar-phosphate backbone in DNA is deoxyribose and RNA’s sugar is ribose (Primary structure diff.)
- RNA has uracil instead of thymine (Primary structure diff.)
- RNA is single-stranded and DNA is double-stranded (Secondary structure), therefore making RNA less stable
- The OH group on ribose is much more reactive than the H in deoxyribose
10
Q
Primary structure of RNA
A
Linear structure of bases, extending from a sugar-phosphate backbone
11
Q
Secondary structure of RNA
A
Double helical stem and unpaired loop
12
Q
Tertiary Structure of RNA
A
Pseudoknots and more complex, weird loops
13
Q
Three components of nucleotides
A
- Phosphate group
- Five carbon sugar
- Nitrogenous base
14
Q
Between RNA and DNA which has the sugar with a hydroxyl group (OH) on the 2’?
A
RNA has the OH, DNA just has an H (hence the DEOXY…)
15
Q
The relation between amino acid and polypeptide is similar to the relationship between
a) phospholipid and plasma membrane
b) nucleotide and nucleic acid
c) glycogen and glucose
d) triglycerides and steroids
A
b
16
Q
How do nucleotides polymerize to form nucleic acids? What bonds form between nucleotides?
A
Condensation reaction; phosphodiester bond, a covalent bond between the sugar of one nucleotide and the phosphate of a second
17
Q
How is the double helix stabilized?
A
- Hydrogen bonding between the base pairs
- Hydrophobic interactions (what causes the DNA to twist)
- Van der Waals interactions (what forms base stacking)
18
Q
Which bases pairs have three hydrogen bonds? (Hint: think about how which base pairs are have a faithful marriage when in DNA and RNA)
A
Guanine and Cytosine.
Adenine (the cheater) has two bonds with both thymine and uracil.
19
Q
Which RNA structure will form spontaneously?
A
Secondary
20
Q
In RNA’s secondary and tertiary structures, the bases participating in hydrogen bonding are ___.
A
antiparallel
21
Q
Carbohydrate monomers
A
monosaccharides
22
Q
Oligosaccharides = __ sugars
A
Few
23
Q
Polysaccharides = __ sugars
A
Many
24
Q
4 ways carbohydrates differ
A
- Aldose or ketone placement of the carbonyl group
- Number of carbon
- Different arrangement of hydroxyl groups in space
- Linear and alternative ring forms
25
What is the carbohydrate molecular formula?
(CH2O)n
n= # carbon hydrates
ranges 3=1000+
26
Where is the carbonyl group located on an aldose?
The end of a carbon chain
27
Where is the carbonyl on a ketose?
Within the carbon chain
28
___ can be used as a source of carbon atoms or energy. ___ must be converted to (first blank) first.
Glucose, Galactose, Glucose
29
Phosphodiester is between __' phosphate group and __' hydroxyl group
5, 3
30
N-terminus vs C-terminus
N has amino
C has carboxyl
31
Purines will always bind to ___
pyrimidines
32
Steps in DNA replication
1. Strand separation (breaking of hydrogen bonds)
2. Complementary base pairing
3. Polymerization
33
True or False: RNA is more diverse in size and shape compared to DNA
True
34
What is the function of a ribozyme
To catalyze reactions (have active sites like proteins)
35
Carbohydrates would be considered
a) polar
b) nonpolar
c) hydrophobic
d) hydrophilic
a and d
36
5 types of carbohydrates
1. Starch
2. Cellulose
3. Glycogen
4. Chitin
5. Peptidoglycan
37
OH placement on glucose and galactose
glucose: behind plane
galactose: above plane
38
The predominant form of glucose dissolved in an aqueous solution is __.
the ring configuration
39
Aldose and ketone are both __
carbonyls
40
Pentose is in ___.
DNA
41
What are two things you can look at to distinguish carbohydrates?
1. # of carbon atoms
2. OH orientation
42
Monosaccharides polymerize via ___ reaction and form ___ linkages
condensation, glycosidic
43
2 most common glycosidic linkages
1. alpha 1-4
2. beta 1-4
1 and 4 refers to the C-1 and c-4
44
A glycosidic linkage is analogous to __ in proteins and ___ in nucleic acids
Peptide, phosphodiester
45
5 types of polysaccharides
1. Starch
2. Glycogen
3. Cellulose
4. Chitin
5. Peptidoglycan
46
Starch is energy storage in ___ cells. and has __ glucose monomers, forming an ___ helix
plant, alpha, alpha
47
Amylose has an alpha-_ glycosidic linkage and amylopectin has an alpha 1-_ glycosidic linkage. Which one has a branching structure?
4, 6, amylopectin
48
Glycogen is energy storage in __ and it's stored in the __ and __.
animals, liver, muscle
49
Glycogen can be broken into __ monomers for energy and has a ___ alpha glucose polymer (1-6).
glucose, branched
50
Cellulose is a ___ polymer and has a __ 1-4 glycosidic linkage. It has __ bonds between adjacent parallel strands.
structural, beta, hydrogen
51
Cellulose is a major component of the __ __ in plant cells.
cell wall
52
True or false: Cellulose is not a linear molecule
False, it is linear and looks like a ladder (hydrogen bonds are the rungs)
53
Similar to cellulose, chitin is a ___ polymer.
structural
54
Chitin is a major component of the cell wall of __ and the exoskeleton for __ and __.
fungi, insects, crustaceans
55
Chitin has a beta __ glycosidic linkage and it has hydrogen bonds between ___ parallel strands.
1-4, adjacent
56
Peptidoglycan is found in __ cell walls.
bacterial
57
All of the structural carbohydrates have __ structures.
linear
58
Peptidoglycan has a __ 1-4 glycosidic linkage and ___ bonds between adjacent strands (make it a bit stronger).
beta, peptide
59
Glycosidic bonds form between what groups?
hydroxyl
60
Why can animals easily degrade starch, but not cellulose?
Animals can degrade alpha 1-4 but not beta 1-4
61
Cellulose, chitin, and peptidoglycan form short/long strands.
long
61
4 functions of carbohydrates
1. Precursors for many different types of molecules
2. Structural support
3. Cell identity
4. Storage of chemical energy
62
Two reasons why beta 1-4 glycosidic linkages do NOT hydrolyze easily
1. Most organisms lack the enzymes to hydrolyze them
2. Fibers exclude water, making hydrolysis difficult
63
2 structures important for cell identity function
1. Glycoproteins- protein+carb
2. Glycolipids- lipid+carb
64
What is cell-to-cell recognition?
When cells can identify themselves
65
Cell-cell signaling
communication b/w cells
66
C-O bonds are held tightly and have high/low potential energy.
C-H/C-C bonds are weaker and have high/low potential energy.
low, high
67
3 types of lipids
1. Fats
2. Steroids
3. Phospholipids
68
All three types of lipids found in cells are insoluble in water because they all possess __
a) fatty acids
b) many ester linkages
c) lots of hydrocarbons
c
69
Why is a plasma membrane necessary?
- keeps all organelles inside the cell
- facilitates what goes in and out the cell
- important in chemical reactions
- creates different concentration gradients
70
What are key parts of lipid structure?
1. Carbon containing compounds
2. HYDROCARBONS
3. Nonpolar C-C and C-H
VERY hydrophobic
71
Fatty acids are a hydrocarbon chain with around __ to __ carbon atoms and a ___ functional group.
14, 20, carboxyl
72
What are the two types of fatty acids, which one has the double bond?
1. Unsaturated, has the double bond
2. Saturated
73
What can the double bond create in unsaturated fatty acids?
Kinks, meaning unsaturated fatty acids can be polyunsaturated
74
Three S's: Saturated, ___, and ___
single (bonds), solid (because long tails are stiff)
75
Which ones has the max amount of Hydrogens, unsaturated or saturated?
Saturated
76
Unsaturated bonds have long or short bonds?
short
77
Steroids have a bulky __ __ structure.
four-ring
78
How do steroids differ?
By functional groups attached to the C's in the ring
79
Lipids always have a ___ and ___ section.
polar (head), nonpolar (tail)
80
Fats, or triglycerides, have three fatty acids linked to a ___. Fats are useful for storing ___.
glycerol, energy
81
Do fats or carbs store more energy? Why?
Fats, because they have high energy bonds (equal sharing, non covalent)
82
When a dehydration reaction takes place to form a triglyceride, what sort of linkage is formed? How many are in a triglyceride?
Ester linkage, three
83
An ester linkage forms between a hydroxyl group of a ___ and a carboxyl group of a ___ ___ ___.
glycerol, free fatty acid
84
Phospholipids are a glycerol linked to a ___ group and two ___ chains. They form cell membranes in ___ environment.
phosphate, hydrocarbon, aqueous
85
Bacteria and Eukarya have __ __ tails and Archaea have ___ tails
fatty acid, isoprenoid
86
What type of chemical interaction do phospholipid have with their environment?
a) only hydrophobic
b) amphipathic
c) covalent
d) only hydrophilic
b
87
Amphipathic is a quality ALL lipids share, meaning they have a hydrophilic ___ and hydrophobic ___.
head, tail
88
Parts of a lipid head
- glycerol
- phosphate (negative charge)
- charged polar group
89
Parts of a lipid tail
- nonpolar
- no hydrogen bonds
90
What does the lipid head and tail form together?
Phospholipid bilayer
91
Hormones and ligands are part of what lipid function?
Cell signaling
92
5 main lipid functions
1. Store chemical energy
2. Act as pigments that capture sunlight (chlorophyll)
3. Serve as signals between cells
4. Form waterproof coating on skin and cells
5. Act as vitamins in cellular processes
93
Lipid bilayers show ___ permeability
selective
94
What passes through lipid bilayer the easiest?
Small, nonpolar molecules
ex: O2, CO2, N2
95
What passes the lipid bilayer from easiest to hardest?
1. Small, non polar/uncharged
2. Small, charged (ex:H2O)
3. Large, uncharged, polar (ex: glucose)
4. Small ions
96
4 factors that affect permeability
1. Length of hydrocarbon tails
2. Saturation state of hydrocarbon tails
3. Presence of cholesterol
4. Temperature
97
Permeability =
Fluidity
98
Which is MORE fluid, short or long tails?
Short, because there are less van der Waals and less packing
99
Which is LESS fluid, saturated or unsaturated?
Unsaturated, because the double bonds can lead to kinks
100
Does cholesterol reduce or increase membrane permeability?
Reduce, because it increase packing density
101
Fluidity increase as the temperature goes ___
up.
102
Diffusion or Osmosis
-spontaneous
-molecules and ions
-based on concentration gradient
-high to low concentration
Diffusion
103
What is the end goal of osmosis AND diffusion?
Equilibrium
104
After diffusion reaches equilibrium, will molecules still move around?
Yes, but there will be no more net movement
105
Is diffusion active or passive transport?
Passive, not energy required
106
What are the two conditions for osmosis to occur?
- there has to be a concentration gradient
- membrane only allows water to pass through
107
Hypertonic
Solution OUTSIDE concentration is HIGHER than concentration inside than the cell
108
Hypotonic
Solution OUTSIDE the cell is LOWER than concentration outside the cell.
109
For a hypertonic solution, water will move__ the cell, resulting in __ of the cell
out, shrinking
110
For a hypotonic solution, water will move __ the cell, resulting in __ of the cell
into, swelling/bursting
111
How does the cell change in an isotonic solution?
It doesn't
112
Isotonic
Inside cell and solution concentration are equal, no net water movement
113
Integral membrane proteins, also known as ___ proteins, are proteins that span the ___ and have segments facing both interior and exterior surfaces.
transmembrane, membrane
114
___ membrane proteins bind to the membrane lipid without passing through.
Peripheral
115
True or False:
Peripheral membrane proteins are only found on the exterior of the cell.
False, they can be found on the exterior and the interior
116
Fluid mosaic model
A dynamic structure with proteins floating in or on the fluid lipid bilayer.
117
___ can be use to isolate proteins from membranes.
Detergents
118
Detergents are/are not water soluble, unlike other amphipathic molecules
are
119
What is the function of membrane proteins?
They assist in cell signaling and transport of substances
120
Receptors are ___ proteins.
signaling
121
3 types of integral proteins
1. Channels
2. Carrier
3. Pump
122
Channel proteins help facilitate ___.
Diffusion
123
Ion channels form __ in the membrane allowing for ions to pass through the membrane.
Pores
124
Ion channels are involved in ___ and ___ diffusion, going ___ the concentration gradient.
passive, facilitated, with
125
____ gradient establishes both concentration gradient AND charge gradient.
Electrochemical gradient (key idea is CHARGE)
126
Gated channels regulate ___.
Movement
ex: voltage and ligand
127
How do gated channels open and close?
In response to a signal
-binding of a certain molecule
-change in voltage
128
Molecules that move down a concentration gradient and require transport proteins to cross a membrane use __ __.
facilitated diffusion
129
Carrier proteins move substances via ___ changes.
structural
(the whole protein changes shape)
130
Carrier proteins selectively pick up ___ on one side of the membrane and drop it on the other side.
solute
131
Passive transports moves __ the gradient, does/doesn't need the input of energy, and includes channels or __.
with, doesn't, carriers
132
Active Transport three A's
Active
Against (gradient)
ATP
133
The Sodium-Potassium pump is ___ transport and uses __+/ __= ATPase.
active, sodium, potassium
134
Pumps are ___ the concentration gradient
against
135
Protein functions
- speed up reactions
- structures
- defense
136
Eukaryotes v.s Prokaryotes main difference
-Prokaryotes do NOT have a membrane-bound nucleus
137
Are the following eukaryotes or prokaryotes?
Eukarya
Archaea
Bacteria
Eukaryote, prokaryote, prokaryote
138
4 parts of a prokaryote
1. At least one chromosome
2. Protein-synthesizing ribosomes
3. Phospholipid membrane
4. Cytoplasm
139
Prokaryotes have chromosomes that are organized into a ___.
nucleoid
140
___ are circular, supercoiled DNA molecules.
Plasmids
141
Ribosomes manufacture ___ in a process known as translation.
proteins
142
Photosynthetic membranes are in ___, and they contain multiple membrane layers.
bacteria
143
What is the benefit of having organelles?
- separation of incompatible chemical reactions
- increases efficiency
144
Nucleus is surrounded by a _____ with pores and has a distinct region named, ___, which is where rRNA is synthesized
double membrane/nuclear envelope, nucleolus
145
Nucleus stores __
chromosomes
146
Nuclear lamina function
structural support
147
Ribosomes are either free in the ___ or attached to the ___
cytosol, ER
148
The ER is continuous with the ____ ____
nuclear envelope
149
3 main functions of rough ER
synthsized proteins that will be
- shipped to another organelle
- inserted into plasma membrane
- secreted to cell exterior
150
Smooth ER lacks ___ and is a reserve for ____ ions
ribosomes, Ca2+
151
The ___ ER is what synthesizes lipids/ breaks down poisonous lipids.
smooth
152
Golgi apparatus is a series of flat membrane sacs called ___. Has two sides, ___ and ___.
cisternae, cis and trans
153
Golgi apparatus processes, sorts, and ships ___ synthesized in the rough ER.
proteins
154
___ side of Golgi receives rough ER products and the ___ ships them out.
Cis, trans
155
Lysosomes contain around ___ different enzymes and have acid ___.
40, hydrolase
156
3 functions of lysosomes
1. Recycling (in animal cells)
2. Hydrolyzing macromolecules
3. Acid hydrolases=digestive enzymes
157
Cell wall forms a protective ___.
exoskeleton
158
Which two structures of bacterial surfaces enable movement and attachment?
- flagella (long to propel)
- fimbrae (needles to attach)
159
Which structure is common to plant and animal cell?
mitochondria
160
Eukaryotes are about __X bigger than prokaryotes.
10
161
Ribosomes are not considered organelles because they lack a ___.
membrane
162
If the smooth ER breaks down proteins, would liver cells have more or less smooth ER.
more
163
What pH do lysosomes work best at?
around 5
164
Vacuole structure
- prominent
- found in plants, fungi, and other eukaryotes
165
Vacuoles can digest but their main function is to store:
1.
2.
3.
4.
1. Water
2. Ions
3. Proteins
4. Pigments or noxious compounds
166
Peroxisome structure
- globular organelles (all eukaryotes)
167
Peroxisomes are the site of what reactions?
Redox
168
___ is to recycle and degrade as ___ is to detox.
Lysosome, peroxisome
169
Why would a double membrane be useful in mitochondria?
For cellular respiration reactions
170
Chloroplasts have a lot a membranes (like mitochondria) for photosynthesis and they are called ___.
thylakoid
171
Endosymbiosis Theory
Mitochondria and chloroplasts were one free-living bacteria. Evidence is:
- they have their own DNA
- they have their own ribosomes
- they can self replicate
172
Thylakoids, DNA and ribosomes are all components found in ___.
chloroplasts
173
Cytoskeleton 3 structures
1. Actin filaments/ microfilaments
2. Intermediate filaments
3. Microtubules
174
Cytoskeleton 4 functions
- system of protein fibers
- gives cell shape and stability
- transports materials within cell
- organizes organelles
175
3 organisms that have a cell wall
1. plant
2. algae
3. fungi
176
Animal cells don't have a cell wall, they have an ___ ___.
extracellular matrix
176
Things that are allow to pass the nuclear pore will have a ___.
tag/signal (coded in)
177
What can enter the nucleus?
Anything involved in DNA and RNA synthesis.
178
If one adds the nuclear localization signal to a cytosolic protein, what will happen?
Rather than going to the cytosol, it can enter the nucleus
179
What is the endomembrane system function?
Shuttle proteins to the right destinations in the cell
180
A protein lacking a signal sequence will likely reside in the ___.
cytoplasm
181
Parts of the Endomembrane System/Secretory Pathway
1. Protein is made by ribosomes and is sent to
Rough ER
2. Enter the ER and protein is folded
3. A vesicle buds off ER, fusing with the cis- side of Golgi
182
3 processes lysosomes go through for protein recycling
1. Receptor-mediated endocytosis
2. Phagocytosis
3. Autophagy
183
Endocytosis is when materials ___ the cell and bind to ____, forming endocytic vesicles and developing into a ___.
enter, receptors, lysosome
184
Phagocytosis forms ___ , which fuses with lysosomes
phagosomes
185
Autophagy (same eating) has to with ___ organelles.
damaged
186
Many cell movements are based on ____ - ____ interactions.
actin-myosin
187
Actin is important in ____ and cytokinesis.
muscles
188
Nuclear lamina is made up of ____ ____.
intermediate filaments
189
Intermediate filaments help ___ the nucleus and anchor ____.
shape, chromosomes
190
____ serve as tracks for vesicle transport.
Microtubules
191
Flagella and cilia are made up of ___.
microtubules
192
Which is NOT a function of actin?
a) maintain cell shape
b) move chromosomes
c) move cells and organelles
d) divide animal cells in two
b, microtubules move chromosomes
193
NLS stands for:
nuclear localization signal
194
Structure =
Function
195
___ are highly organized and regulated
Cells
