week 6 Flashcards
(208 cards)
1
Q
is a liquid that is a homogeneous
mixture of substances.
A
solution
2
Q
is the dissolving agent of a solution
A
solvent
3
Q
is the substance that is dissolved.
A
solute
4
Q
aqueous solution
A
is one in which water is
the solvent
5
Q
substance is one that does
not have an affinity for water.
A
hydrophobic
6
Q
hydrophilic
A
substance is one that has an
affinity for water.
7
Q
template strand
A
the strand of the DNA double helix
used to make messenger RNA
8
Q
the
strand of the DNA that is
complementary to the template strand
A
coding strand
9
Q
the enzyme that
synthesises
RNA
from the DNA template
A
RNA polymerase
10
Q
information for a trait passed from parent to offspring
A
gene
11
Q
alternate forms of a gene
A
alleles
12
Q
homozyguous
A
having 2 of the same allele
13
Q
heterozygous
A
having 2 different alleles
14
Q
total set of alleles of an individua
A
genotype
15
Q
outward appearance of an individual
A
phenotype
16
Q
Mendel’s 1st Law of Inheritance
A
principle of segregation
17
Q
Principle of Independent Assortment
A
Mendel’s 2
nd
Law of Inheritance
18
Q
ligand
A
the signaling molecule
19
Q
receptor protein
A
the molecule to which the
receptor binds
20
Q
intracellular receptor
intracellular receptor
A
located within the cell
21
Q
cell surface receptor
or
membrane
receptor
A
located on the plasma
membrane to bind a ligand outside the cell
22
Q
Reception
A
a signal molecule binds to a receptor
protein, causing it to change shape
23
Q
signal transduction
:
A
the events within the cell that
occur in response to a signal
24
Q
The three stages of cell signalling:
A
reception, – transduction, – and response
25
```
ion
channel linked receptors
– ion
channel that opens in response to a ligand
2.
Enzyme linked receptors- receptor
tyrosine kinases
– receptor is an enzyme
that is activated by the ligand
3.
G protein-coupled receptors
– a G-
protein (bound to GTP) assists in
transmitting the signal
```
There are 3 subclasses of membrane
| receptors:
26
After glucose enters a cell, insulin binding to its
| receptor triggers enzymatic activity that: (3 things)
Catalyzes the oxidation of glucose for ATP production
–
Polymerizes glucose to form glycogen
–
Converts glucose to fat (particularly in adipose tissue)
27
a series of protein
kinases that phosphorylate each other in
succession
kinase cascade
28
mitogen-activated protein (MAP) kinases
are activated by kinase cascades
29
hydrophobic messengers
steroid and thyroid hormones of animals.
30
steroid hormones
-have a nonpolar, lipid-soluble structure
-can cross the plasma membrane to a
steroid receptor
-usually affect regulation of gene expression
31
what blocks the receptor from binding to DNA until the hormone is present
inhibitor blocks
32
steroid receptor has 3 functional domains
1. hormone-binding domain
2. DNA binding domain
3. domain that interacts with coactivators to
affect gene expression
33
Cell-to-Cell Interactions
Cells can identify each other by cell surface
| markers.
34
tight junctions
create sheets of cells
35
anchoring junctions
connect the
| cytoskeletons of adjacent cells
36
communicating junctions
```
permit small
molecules to pass between cells
a.
gap junctions
– in animal cells
b.
plasmodesmata
– in plant cells
```
37
Protein phosphatases
| remove
the
phosphates from proteins, a process called
dephosphorylation.
38
This phosphorylation and dephosphorylation
| system acts as
a molecular switch, turning
| activities on and off.
39
Cyclic AMP
| cAMP
is one of the most widely
| used second messengers.
40
Adenylyl cyclase
an enzyme in the plasma
membrane, converts ATP to cAMP in
response to an extracellular signal.
41
Scaffolding proteins
are large relay proteins
| to which other relay proteins are attached.
42
Apoptosis
is programmed or controlled cell
| suicide.
43
Apoptosis can be triggered by:
–
an extracellular death-signalling ligand,
–
DNA damage in the nucleus,
–
or protein misfolding in the endoplasmic reticulum.
44
how man barr bodies in females ?
1
45
the three components of the cell theory
1. all organisms are composed of cells
2. cells are the smallest living things
3. cells arise only from preexisting cells
46
what is: enclosed by a membrane,use dna as genetic info, are about reproduction, repair, growth
Cells
47
what conduct chemical proceses and are energy creators
enzymes
48
domain bacteria and archaea ?
Prokaryotes
49
domain eukarya ? are
Eukayotic
50
single celled and communites have no nucleus have an simple internal structure 0.5-5 um (do have sex)
prokaryotes
51
unicellular or multicellular have nucleus 10-100um
Eukaryotes
52
scientists classify many bacterial species into gram positive and gram negative (negative = more likely to be antibiotic resistant)
Gram stain
53
what is apart of the endomembrance system(a series of membrance throughtout cytoplasm, regulates protein traffic and performs metabolic functions in the cell)
1. endoplasmic rectilum
2. golgi apparatus
3. lysosomes
54
smooth endoplasmic rectilum lacks or does not lack ribosomes ?
lacks ribosomes
55
______ enzymes to break down macromolecules, destroy cells of foreign matter that the cell has engulfed by pagocytosis
Lysosomes
56
in plants what turns fats into carbohydrates
glyoxysomes
57
what is the relationship when one cell engulfs a second cell
it is symbiotic this is the process of endosymbiosis
58
the plasmodesmata includes ?
tight junctions, desmosomes and gap junctions
59
elements making up 96% of the human body CHNOPS
oxygen, carbon, hydrogen, nitrogen
60
covalent bonds is the
sharing of electrons
61
what bond is attracted to oppositely charged parts of neighbouring molecules (is unequal of sharing of electrons in a covelnt bond)
polarity
62
ionic bonds
the attraction between oppositely charged atoms or ions
63
organic = ?
carbon based
64
what matters with isomers ? (carbon compund another carbon compund is functional groups)
shape
65
-Oh (alcohol), -COOH (carboxyl), -NH2 all are
functional groups (carbon compunds)
66
CnH2nOn is ?
a carbohydrate
67
monosaccharides (monomer smallest unit) can be in linear or cyclic forms ? true or false ?
True
68
are dissacharides two monomers which are joined ?
yes
69
complex carbohydrate or carbohydrate ?:
| gycosidic bond between monomers (causes a dehydration reaction)
complex carbohydrates
70
a bond or linkage is a type of covalent bond that joins a carboydrate (sugar) molecule to another group, which may or may not be another carbohydrate
Glycosidic
71
a somatic cell, for growth and repair name this process
Mitosis
72
focus on reproduction name this process
reproduce
73
how many chrocomsomes in a set
46, 23 in somatic cells
74
prophase
start
75
prometaphase
organising
76
metaphase
line up
77
ananphase
parting, splitting
78
telophase
the division of one nucleus into 2 genetically identical nuclei = complete
79
interphase
very begginning
80
another round of cell division the sister chromotids finally seperate into four haploid duagters result
meiosis
81
in the cell divison/growth cycle what is G1
primary growth
82
in the cell divison/growth cycle S
dna synthesis leading to chromosme duplication
83
in the cell divison/growth cycle G2
secondary growth
84
what is the process called of the formation of the constriction belt of contractile ring from microfilaments, cleavage of cell into two identical halves
Cytokinesis
85
what are gametes
egg and sperm - produced y meiosis
86
zygote ?
fertilised egg
87
fertilisation/syngamy restores ?
diploid numbers
88
what gives rise to variation in organisms
- crossing over (prophase)
- independent assortment
- dating (random assortment)
89
what gives 2 daughter cells
mitosis
90
what gives 4 daugter cells
meiosis
91
diploid ?
contain pairs of chromosomes (somatic)
92
one of each pair of chromosomes ? is ?
haploid cells (germ cells > gametes)
93
is each bit of dna copied (replicated) t or f
True
94
are nucleic acids macromolecules ?
yes
95
dna= genetic infor, rna= translating the genetic info yes or no ?
yes
96
what is composed of this:
5 carbon sugar (deoxybriose in ___ and ribose in ___)
a phosphate group (PO-4)
a nitrogen containing base that may be purine (A, G) OR PYRIMIDINE (T,C)
Dna and rna
97
what are nucleotides composed of ?
- a nitrogenus base
- a phosphate group ('5')
- free hydroxyl ('3')
98
nucleotides are connected in a long chain called ?
a polymer
99
the phophodiester bond
is the bond of adjacent nucleotides
100
what is of '5' to '3' orientation ?
the polymer chain
101
what is the double helix composed of ?
2 sugar phosphate backbone, ntrogenus bases facing towards the interior of the molecule, bases form hydrogen bonds
102
replication or cell division comes first ?
dna replication
103
what is the 3 stages of the replication of DNA ?
1. intiation (replication begins at an origin of replication)
2. elongation (new strands of DNA are synthesised by DNA polymerase)
3. termination(end of the replication cycle replication is terminated differntly in prokaryootes and eukaryotes)
104
a repaeated nucleotide that bind an indicator protein
| - and and AT rich sequence that can be easily opened for intiation
OriC
105
is dna replication semi discontinuos ? why ?
yes, beacusr one strand is contiuous while the other is discontiuous
106
what is replisome
is assembled at the replication fork
1. primose (primase, helicase, proteins)
2. dna pol III enzymes
107
eukaryotic dna replication is more complex than prokaryotic ?
yes
108
do chromosomes have a primer ?
no
109
a method for determining telomere length and its use in assessing age in blood and saliva
aging papers
110
damage to dna effects ?
dna sequence
dna damage
the damage can be radiation or phsical agents which = mutation
(corrections cellular dna repair mechanisms)
111
the membranes structure is a double layer of ?
phospholipids
112
a membrane is a fluid structure with a 'mosaic' of various proteins embedded in it
the fluid mosaic model
113
cholesterol causes a warm temperature this causes ?
restraint movemnt of phospholipids p with phospholipids a cool temp maintains fluidity by preventing tight packing
114
what is the permeability of the lipid bilayer
hydrophobic (non polar) yes
| polar (sugars) no
115
what is osmosis
diffusion of water across a selectively permeable membrane
116
created by difference in the distribution of positive and negative ions
is voltage
117
how do ion pumps maintain membrane potentioal
- electrochemical gradient
chemical force(ionic concentration gradient)
-electrical force
118
how to small molecule pass the bilayer
transport proteins
119
how to large molecules cross the bilayer
cross membrance in bulk (energy) \
120
what is phagocytosis
cellular eating
121
what is pinocytosis
cellular drinking
122
is diffucion hydrophobic of hydrophillic
hydrophobic
123
is facilitated difusion hydrophobic of hydrophillic
hydrophillic
124
are all enzymes proteins
yes
125
are all proteins enzymes
no
126
is a monomer a amino acid
yes
127
how many amino acids in a monomer protein
20 common amino acids, 9 essential
128
example of mutation
sickle cell anaemia
129
proteins ar epolymers of ?
amino acids
130
what can misfolding cause ?
denaturation/disease
131
list a few features of enzymes
biological catalysts
specific
induced fit model
control
132
is water polar ?
yes
133
what does the polarity of water allow ?
allows water molecules to form hydrogen bonds with eahc other (h bonds stabilise biomolecules)
134
4 of waters properties
- cohesive behaviour
- ability to moderate temp
- expansion upon freezing
- versatility as a solvent
135
what does cohesion help in plants
helps transport of water sgainst gravity in plants
136
attraction between different substances
adhesion
137
measure of how hard itis to break the surface of a liquid mn/m
surface tension
138
water/1cal/g/degrees celcicius
---
139
heat is ____ when hydogen bonds break
absorbed
140
heat is ___ when hydrogen bonds form
released
141
what does evaporative cooling ddo ?
stabilises temp in organisms and bodies of water
142
why does ice float in liquid water ?
because hydrogen bonds in ice are more "ordered", making ice less dense
143
an ionic compund dissolved in water, each ion is surrounded by a sphere of water molecules
hydration shell
144
what is a colloid
a stable suspension of fine particles in a liquid
145
h bonding between water molecules makes ____ instantaneous
dissociation
146
if the solution were to differ by 1 ph unit one contaains 10x more H+
___
147
ph declines as ? what increases
H+
148
the more H+
acid (proton donor)
149
the less H+
base (proton acceptor)
150
what are buffers ?
resist changes in PH, weak acid and conjugate bases, aqueous
151
energy can neither be created nor destroyed, but it can be transfered or transformed
first law of thermodynamics
152
2nd law of thermodynamics
the universe tends to disorder
153
what is gibbs free energy
energy to do work, exergonic, endergonic
154
atp is the currency for ?
cells
155
respiration gains
ATP which is the oxidation of glucose
156
metabolism= ?
anabolism+catabolism
157
multi enzyme complex has ?
3 different reactions, 3 different enzymes
158
what is the evolution of eukaryotes called ?
endosymbiosis
159
electron carries in photosynthesis ?
plastoquinone
plastocyanin
ferredoxin
160
rRna
translates (ribosome rna)
161
trna
transfers (transfer rna)
162
DNA is _____ to make MRNA which is ____ to make protein
transcribed
| translated
163
flow of info from dna to rna
transcription
164
flow of info rna to protein
translation
165
how many codons in total ?
64
61 encode all 20 amino acids
3 codons are stop codons
AUG start codon
166
T in the DNA is replaced by U in the RNA
__
167
core polymerase has how many subunits ?
5
168
how many subunits in polmerase
4
169
intiation needs ?
a promoter and a start site
170
elongation encounters the ?
trranscription bubble
171
transcription and translation are often couple occuring at the same time this happens with ?
prokaryotes
172
what has 3 RNA polymerases
eukaryotes
173
non coding sequences (not translated)
INTRONS
174
Exons ?
sequences that will be translated
175
2 features of the ribosomes role
1/ to decode mrna
| 2. to form peptide bonds between amino acis (=polypeptide)
176
effects of allele (observe)
dominant
177
the effect of the allele arent always observed
recessive
178
carriers ?
allele that gives rise to an abnormality where the disease causing allele is recesive
179
multiple genes are involved in controlling the phenotype of a trait- contiuuus variation (quantitative traits)
polygenic inheritence
180
pleiotrophy
refers to an allele which has mmore than one effect on the phenotype eg sickle cell anaemia
181
incomplete dominance
heterozygote is intermediate in phenotype between the 2 homozygotes
182
codominance
the heterozygote shows ssome aspect of the phenotypes of both homozygotes
183
agents of evolutionary change
- mutation
- gene fliw
- non random dating
- assortive mating
- disassortative mating
- genetic drift
- selection (artificial, natuarl>variation must exist, pesticide resistance)
184
paracrine signalling
released from cell effects neighbour
185
endocrine signalling
hormones release affect other cells
186
synaptic signalling
nerve cells release the signal bind to receptos or nearby cells
187
phosphorlation phosphates from ?
Atp to protein
188
calcium regulates its ___
concentration
189
where is the krebs cycle located ?
matrix of the mitochondria
190
the division kf the cytoplasm is caused by ?
a contracting ring
191
the addition or removal of a phosphate group can expose or hide potential binding sites in ?
proteins
192
on balance for every molecule of glucose produced glycolysis produces
two molecules of ATP and two molecules if NADH
193
transmembrane protein channels allow
direct and fast passage from one side of a membrane to the other
194
communicating junctions are protein channels that
allow ions to cross freely between cells
195
humans who have lost even one copy of an autosome are called
monosomics
196
in anjmal cells cytokinesis is
prevented by drugs that disrupt the actin fibres
197
small molecules or ions can pass from one cell to another through
gap junctions
198
the replisome has two main subcomponents
the primosome and a complex of two DNA pol III enzymes
199
what is central dogma
dna>rna>proteins
200
on balancs for every molecule of glucose processed,glycolysis produces a net gain of
two molecules of ATP and 2 molecules of NADH
201
what makes one amino acid different from one another
different side chain (R groups) attached to an alpha carbon
202
protein synthesis in eukaryotic cells
cytoplasm
203
whats not apart of a prokaryotic cell
the ER
204
what are the major structural components of the cell membrane
phospholipids, cholesterol,proteins
205
the partial negative charge in a molecule of water occurs because
the electrons shared between the oxygen and hydrogen atoms spend more time around the oxygen atom nucleus than around the hydrogen atom nucleus
206
single strand binding protein
binds to and stabilises single stranded DNA until it can be used as a template
207
topoisomerase
relieves overwinding strain ahead of replication forks by breaking,seiveling and rejoining dna strands
208
syntesises an rna primer at 5 end of leading strand and of each okazaki fragment ofl agging strand
primase
