midterm 1 concepts Flashcards
(149 cards)
1
Q
RNA is formed by the formation of covalent bonds between _______ of nucleotides
A
5 prime phosphate group and 3 prime hydroxyl group
2
Q
A Phospholipid is
A
glycerol, two fatty acids containing a phosphate group
3
Q
what is a carbohydrate and what is the different between a disaccharide and a polysaccharide
A
A carbohydrate includes sugars and polymers of sugars, the most common Monosaccharaide is glucose and when there is in a chain it can be a di(2 of them ) or poly which is multiple
4
Q
what are examples of lipids and characteristics
A
phospolipids, fats and steroids - hard to mix in water, and a lot of hydrocarbon regions
5
Q
What are fats consist of
A
includes glycerol and fatty acid, glycerol connect by a coc bond
6
Q
what is the bond between a fatty acid in a triglyceride (creates a fat which is water fearing) reaction called
A
Easter Linkage
7
Q
What is the different between saturated and unsaturated fats
A
Saturated fatty acids have the maximum number of hydrogen atoms possible and no double bonds
Unsaturated fatty acids have one or more double bonds
8
Q
what is a phospholipid made of
A
two fatty acids and a phosphate group are attached to a glycerol
9
Q
what parts of a phsophoLIPID are hydrophobic or hydrophilic
A
the two fatty acids attached are hydrophobic and the phosphate group and its attachment with glycerol make it hydrophilic because of the c-o and po bonds . This whole thing is amphipathic means it has both basically
10
Q
how phospolipids arranged
A
The hydrophobic part hence the fatty acids are in the inside. Most cells react with water so u want the hydrophilic part on the outer side
11
Q
how are steroids characterized
A
they are lipids, with a carbon skeleteon of four rings
12
Q
name an example of a type of steroid
A
cholestrol present in animal cell memebrans
13
Q
what are some functions of protein
A
defense storage support etc
14
Q
what is an amino acid
A
organic molecules with amino and carboxyl groups
15
Q
amino acids
A
organic molecules with amino and carboxyl groups
16
Q
Polypeptide
A
this is the unbranched polymers built from these amino acid
17
Q
peptide bond
A
covalent bond between amin acids
18
Q
polypepetide
A
polymer of amino acids
19
Q
what determines a proteins specific activities
A
its three dimensional architecture which is determined by the sequence of amin acids
20
Q
Primary strucutre of a protein
A
this is the unique sequence of amino acids
21
Q
Why is butter a solid at room temperature, while vegetable oil is a liquid?
A
Butter is a saturated fat, meaning its molecules can pack closely together because they do not have a kink. This makes it easier to solidify than vegetable oil, which is an unsaturated fat and has a kink that makes its molecules less likely to pack together.
22
Q
Which of the following occurs when hydrogen is reacted with vegetable oil?
A
When hydrogenated, the oil will be solid at room temperature. This process of hydrogenation creates trans fats, which can result in many health problems.
23
Q
what kind of bonds holds carbohydrates together
A
glyosidic bonds
24
Q
what is the composotion of DNa
A
Deoxyribose, phosphate group, nitrogenous base
25
What is the composition of RNA
Ribose, phosphate group, nitrogenous base
26
what is a nucleotide and give an example
a nucleotide is a nitrogenous base a sugar and a phosphate think ATP, adenine sugar triphosphate
27
what is an example of a nucleoside
this is a base and sugar an example would be adenine which is bound to a deoxyrobose sugar
28
strucutrally what is the difference between RNA and Dna
Dna follows a double helix wile rna is a single strand making it more movable
29
what are the first and second law of thermodynamics
first law- energy cannot be created or destroyed
second law- every energy trasnfer increases the entropy in the universe
30
what is the different between catabolic and anabolic reactions
catabolic pathways release energy by breaking down bonds
anabolic consume energy to build bonds
31
how does metablism work
it constantly is loosing nergy so cells conintue to do work
32
what are the functions of atp
energy coupling the release of a phosphate creates energy that is used to drive an energonic process
33
what is a substrate
the reactant that an enzyme acts on
34
what is an active site
the place where the enzyme binds to a substrate, the shape of the active site and substrate explains the function of the enzyme
35
what are cofactors
nonprotein helpers that bind to the enzyme permanently or reversibility with the substrate. Coenzymes are like vitamins
36
what is a competitive inhibitor
similar to substrate and can bind to the active site
37
noncompetetive inhibitor
binds to another part of the enzyme away from the active site which changes shape making it less effective
38
what characrizes prokaryotic cells
they have no nucleous, cytoplasm in the membrane
39
euroakarytoic cells are characterized by
dna in a nucleus bounded by a double membrane,, larger, cytoplasm between membrane and nucelus
40
what is the plasma membrane
the plasma membrane is a selective barrier that allows sufficient passage of oxygen, nutrients and waste to service volume of every cell, think of it as a way to trasnport things
41
what is the basic fabric of membranes made of
phospholipids, therefore the hydrophilic area is on the outside
42
what is the purpose of the nucleus
has most of the cells genes
43
describe the nuclear envelope
it encloses the nucelus seperating it from the cytoplasm
44
describe what purpose of ribosomes
made of rna and protein responsible for protein synthesis located in cytosol and endoplasim reticulum
45
what is the difference between prokaryotic cell and euroakryotic cell
prokaryotic cellls dont have a nucelus, with unbound dna, no membrane organelles
46
what is the goli apparetus
modifies products of the enendoplastmic reccutulum, sorts and packages materials
47
what is endoplasmic reticulum
outer part of the nucleous, there is rough and smooth er, rough er has bound ribosomes, which secrete glyco proteins and districbute transport vesicles
smooth er synthesizes lipids and detoxifies
48
what are lyosomes
help engulf another cell by phagocytosis ciruclar near er
49
what are vacuoles
large vesicles derived from the ER and Golgi
food vacuoles- formed by phagocytosis
contractive vucoles found in fresh water protists, pump excess water out of the cell
central vacuoles found in plans make sap
50
what is the mitochonidra
the sit of cellular respiration uses oxygen to generate atp
51
what is chorloplasts
found in plants allows for photosynthesis, mitochondira and cholorplasts have similartities with bacteria
52
explain what the cytoskeleton is
a network of fibers extending through the cytoplasm , helps to maintain shape and cells structures and activities
53
what is the function of is an allosteric effector?
An allosteric effector is a small molecule that regulates a protein's activity by binding at a binding site different from its active site.
54
What is phosporylation?
The transfer of phosphate groups to molecules that need to do work. ATP-ADP
55
what is chemical coupling?
Some reactions require energy, others yield energy. The coupling of these reactions make it possible for a pathway to continue.
56
what does catabolic mean?
break bonds
57
what does anabolic mean
building up
58
what is kinetic energy
eneryg of motion
59
what is cellular respiration
a process that releases energy by breaking down glucose and food molecules in the prescense of oxygen
60
what is the noncompetitive inhibitor
an inhibitor that binds at a site different from substrates
61
describe the atp cycle
renewing of atp via exegonic and endergonic reactions. THe atp loses its phosphate via exergonic and gains it back via endergonic
62
what is phosytnehsis
the process by which a cell captures energy in sinlight and uses it too make food
63
what is a spontaneious reaction
a reaction that occurs naturally with no outside addition
64
what is an active site
the region an enzyme binds to a protein or other subtance during a reaction
65
what is a substrate
the substrate on which an enzyme acts
66
prokaryotic vs eukaryotic
prokarytoic dont have membrane bound organellles or a nucleous and are usually smaller
67
organelles in euroakryotic cells
endoplasmic reticulum, ribosomes lyosomes, golgi apparatus, mitchondira, nucleus, chloroplasts, centrosomes, vacuoles
68
what is the function of the nucleus
stores DNA
69
what is the function of the cell membrane
regulates what enters and leaves the cell and also protects and supports the cell
70
what is the function of the golgi apparatus
sorts and modifies proteins that have arrived from the rough ER
71
what is the function of the rough ER
transports and exports proteins synthesized at the ribosomes
72
what is the function of the nucleoplasm
maintain shape and structure of nucleus
73
what is the function of the cytoskeleton
help keep a cells shape
74
what is an intergal membrane protein
inegrated in membrane spans entire width of membrane and has hydrophilic and hydrophobic portions
75
what is a peripheral membran protein
attached to the outside loosely associated with proteins or lipids
76
what is the function of the chloroplasts
site of photosynthesis
77
what is the relationship between entropy and free energy
change in free energy is equal to the sum of the enthalpy plus the product of the temperature and entropy of the system there fore if nethalpy increases so does the change in free enrgy
78
how does ATP function as the "energy currency" of the cell.
ATP is an excellent energy storage molecule to use as "currency" due to the phosphate groups that link through phosphodiester bonds
79
why do spontaneous reactions occur slowly
because the activation barrier may be hard to overcome and take a slower time
80
what is amicelle and what does it do
They are sphere shaped water-soluble micelles with polar end on outside and insoluble end on the inside
Take up free fatty acids which are dissolved in the interior of the molecule
Increase surface area while decreasing diameter of particle
Shuttle the emulsion particle to brush border of jejunum for absorption
81
what is the function of a vacuole
to store water
82
what are three types of transport
active trasnport which requires eneryg and a transport protein, passive transport no input of energy
bulk transport larger mlelculues
83
what are membranes made out of and what are these properties
they are mainly phospolipids which means they have water fearing and water loving parts creating a micelle
84
what structure is common to plant and animal cells
mitochondria
85
what does cyanid bind too
mmictochondira
86
where are proteins sorted in the cell
golgi apparatus
87
do phosopholipids flip flop from one layer to another
this is very rare
88
what diffusses easily in a cell
smaller non polar or hydrophobic molecules
89
what does an ion channel mediate
facilitated diffusion, the process where transport proteins speed the passive movment of molecules acorss a plasma membrane, include channel and carrier proteins
90
cells take up fluids and dissolved solutes via
pinocytosis
91
describe osmosis
in osmosis water moves across a membrane from areas of lower solute concentration to areas of higher solute concentration
92
what is the voltage across a membran called
membrane potential
93
what happens to the membrane in colder temperatures
it starts to go from a fluid to a solid state which is why i colder temperatures, animals want to have more unsaturated fats due to the fact this increases solubility
94
explain the importance of cholesterol
cholesterol is a component of membranes that reduces fluidity at moderate temperatures by restraining movement of phospholipids and hinders solidification at low temperatures by disrupting packaging
95
what are the two major types of proteins and describe them
prepipheral proteins , integral proteins , peripheral are bound to the surfaceof the membrane and inegral are found inside and outside. transmembrane proteins are inegral proteins that span the membrane
96
what kind of seconday structure is found in inegral proteinswhat
alpha helix
97
what are some functions of membrane proteins
they exhibit selective permeability because of the fluid moscial model non polar can pass easily polar cant
98
what is the different between channel and carrier proteins
channel proteins are hydrophilic channels that certain molecules use as an molecule or ion
carrier proteins bind to molecules and change shape to transport tthem
these do not requier energy
99
what is diffusion
the movement of particles to spread out evenly in availbale space
100
what kind of transport is diffusion
passsive transport requiere no energy
101
what is osmosis
it is a type of diffusion where water moves across a selectively permeable membrane, free water molecules diffuse across a membrane from a lower solute concentration to a higher solute. Water keeps moving until the solute concentration on both sides is euqal
102
what is tonocity and descirbe the 3 stages
tonicity is an abiity of a surroudning to cause a cell to gain or loose water
a gain in water is called hypotonic which causes the cell to burst or lysed
isotonic is when the at equilibirum
hypertonic is when our cells dont have water which causes it to shrivel
103
describe facilitated diffusion.
transport proteins
channel proteins provide corridors for specific molecules/ ions
aquaporins facilitate diffusion of water
ion channels facilitate the transport of ions . some called gated channels open or close in response to stimulus
104
what is active transport
requires energy to move solutes against a concentration gradient , usually in the form of ATP
105
what kind of proteins are involved in active transport
carrier protiens only
106
what is an electro chemical gradient
drives the diffusion of ions across a membrane , the inside of a cell is negative compared to the outside, favoring passive transport of cations into and anions out
107
what is a elecrogenic pump
generates energy acrros a membrane storing energy that can be used for callular work
108
cotransport occurs
the transport of a solute drives other substances so both arrows going same way
109
what is endocytosis
macromollecules are taken into cell vesicles, there are three different types
phagocytosis eating the cell
pinocytosis cellular drinking
receptor mediated endocytpsos
110
what is exocytosis used for -
vesicles are fused with membrane and release products . example is pancreas releasing insulin
111
what do peroxisomes do
form hydrogen peroxide, helps detoxify
112
cytoskeleton
microtibiles, micro filamanets, help support structure and shape
113
what is the extracellular matrix
regulars a cells behaviour by communitication with a cell through integrins
114
what are the three types of cell junction
a tight juncion, membrans of neighboring cells are pressed together preventing leakage of fluid
desmosomes, fasten cells together
gap junctions provide channels between cells
115
explain what a co factor is
non protein helpers which bind to an anzyme
inrognatnic are metal atoms such as iron
organic cofactors are called coenzymes
116
what is allosteric regulation
the substrate has another sitre that can be binded with anacitavgor or inhibitor
117
what is an ester linkage
bond between monomers of fats
118
what carbon of a sugar does a phosphate group attach too
5
119
what carbon is the base attached to
1
120
in a phosphodiester bond explain what happens
dehydration synthesis where the 3 prime hydroxyl group interacts with the phosphate group
121
what are the major differences between cellulose starch and glycogen can they hydrogen bond
starch and glycogen are used in animals and have alpha glucose subunits while cellulose has a straight rigid structure
122
what is a ketone functional group
carbon double bonded to oxygen
123
aldehyde functional group is
H-C doule bonded to oxygen
124
what is a sulfhydryl group
s-h bond
125
carboxyl group is
it is c bonded with oh think the group founded on the right of amino acids COOHo
126
carbonyl
c double bonded with oxygen and h
127
general structre of an animo acid
NH2-CH-COOH where r group bonds with C
128
what are the generic functions of nucleotides and nucleic acids
nucleic acids such as rna are used in translation and transcription of DNA to produce proteins in cells. Nuceloeitdes are used in RNA synthesis, and energy generation through ATP
129
what are the purines
and what are pyrimidines
purines- adenine and gianine
pyrimines- cytosine uracil thymine
130
describe how size polairty and charges of solutes influence ability to diffuse
small non polar moleculue
131
describe how the size, polarity and charge of solutes influences their ability to diffuse
across pure lipid bilayers
Size: Some polarized molecules are small enough to slip past the lipid tails. For example, water is a polarized molecule, but its small size allows it to freely diffuse across the cell membrane. This is also true of carbon dioxide, the byproduct of cellular metabolism. Oxygen molecules have no polarity and are also small enough to easily diffuse into the cell. Sugar molecules, which contain five or more carbon atoms, are both polar and too large to diffuse through the cell membrane and must travel through transmembrane proteins.
Polarity and Charge: An ion is an atom or molecule that has an outright charge due to an imbalance between the number of protons and electrons. Polarity is an uneven distribution of charge across a molecule, with some partially positive and negative regions. Charged and polarized molecules dissolve in water while uncharged molecules dissolve in lipids. The lipid tails in the cell membrane prevent charged and polarized molecules from diffusing through the cell membrane. However, some cells actively maintain an electric potential on either side of the cell membrane that can attract or repel ions and polarized molecules.
132
Compare and contrast passive diffusion, facilitated diffusion and active transport with reference to the roles of energy and transport proteins in these processe
passive diffusion does not require energy think small not charge mollecules that dissolve, osmosis a form of passive diffusion
facilitated diffusion involves channels , or carrier proteins, there are ion channels for ions, aquoporins etc. Channel proteins fore pore, carrier proteins can transfer amino acids sugars etc
active transport only carrier proteins requires energy
133
Describe how the concentration of solutes on either side of a membrane influences the movement of water via osmosis
water will move from high to low concentration
134
Compare and contrast the roles of carrier proteins and channels in facilitated diffusion
Channel proteins transport substances down the concentration gradient, while carrier proteins transport substances both down and against the concentration gradient. Channel proteins form pores crossing the membrane, thus allowing the target molecules or ions to pass through them by diffusion, without interaction
135
compare and contrast the roles of co-transporters and pumps in active transpo
Pumps can be classified as either primary or secondary active transporters based on the method they use to move ions across the gradient. Primary active transporters are usually transmembrane ATPases, that hydrolyse ATP to produce energy in order to transport ions up a concentration gradient.
136
explain how the sodium-potassium ATPase maintains the electrical potential across the plasma membrane
The sodium-potassium pump goes through cycles of shape changes to help maintain a negative membrane potential. In each cycle, three sodium ions exit the cell, while two potassium ions enter the cell. These ions travel against the concentration gradient, so this process requires ATP
137
Briefly describe the functions of exocytosis and endocytosis
Endocytosis is the process of capturing a substance or particle from outside the cell by engulfing it with the cell membrane, and bringing it into the cell.
Exocytosis describes the process of vesicles fusing with the plasma membrane and releasing their contents to the outside of the cell
138
compare and contrast pinocytosis, phagocytosis and receptor-mediated endocytosis
Phagocytosis is the taking in of large food particles, while pinocytosis takes in liquid particles. Receptor-mediated endocytosis uses special receptor proteins to help carry large particles across the cell membrane
139
Glucose uniport
Located in the basal and lateral domains of the plasma membrane. Passively transports glucose down its gradient for use by other tissues
140
what is a transmembrane protein
its an integral protein that covers the whole membrane
141
Which of the following questions would best help determine if a cell has membrane-bound organelles?
Are there distinct environments within the cell?
Distinct environments are formed by internal membranes, which compartmentalize the cell into different membrane-bound organelles.
142
what do both prokaryoitc and eukaryotic cells have
they both ribosomes
143
A cell is treated with a toxin that prevents the synthesis of new lysosomes. However, the cell continues to produce the hydrolytic enzymes normally found in lysosomes.
In which of the following structures are the hydrolytic enzymes most likely to accumulate?
Golgi complex
Lysosomes are synthesized by the Golgi complex. If new lysosomes aren’t synthesized, and the hydrolytic enzymes continue to be produced, the hydrolytic enzymes will accumulate in the Golgi complex.
144
why is compatibilization helpful
A compartmentalized cell has internal membranes that minimize competing interactions within the cell.
Internal membranes minimize competing interactions within a cell by isolating metabolic processes from each other. This allows multiple metabolic processes to occur at the same time within the cell.
145
when a protein denatures does it effect what structure state you are in
yes, but there is no speicfication
146
Nucleotides are connected by ____ while base pairing occurs via _____
phosphodiester bonds , hydrogen bonds
147
cells are placed in a solution the cells appear to swell and some cells burst this indicates that solution has __ solute concentration then the cytplasm
lower, think osmosis the water woll go into the cell of the cell to create a more equal solute concentration
148
true or false: active transport utilizes energy to transport a molecule with its cocentration gradient
false
149
using terms of surface area and volume describe why it is that cells remain so small
they are compatibilized, cells maintain a high surface area to volume so they can effectively transport molecules and waste in and out of the cell.
