formative summary revision Flashcards
1
Q
what is Km increased by
A
competitive inhibition
2
Q
what is Vmax decreased by
A
non-competitive inhibition
3
Q
allosteric binding
A
sigmoidal curve
4
Q
non-allosteric enzyme
A
hyperbolic curve
5
Q
what are the 3 irreversible stages of glycolysis mediated by enzymes
A
- Hexokinase – substrate entry
- Phosphofructokinase – rate of flow
- Pyruvate kinase – product exit
6
Q
what is metaplasia
A
mature cell transforms into another mature cell
7
Q
dysplasia
A
disorder growth in abnormal cells in tissue
8
Q
what are the hallmarks of cancer
A
- Resisting cell death
- Sustaining proliferative signalling
- Evading growth suppressors
- Activating invasion and metastasis
- Inducing angiogenesis
- Genome instability
9
Q
when is steady state achieved
A
after 5 half lives
10
Q
describe temp control/ negative feedback
A
- Central & peripheral thermoreceptors sense change in temp
- Send signals to hypothalamus
- Hypothalamus sends signals to effectors
- Effectors take action to oppose change
11
Q
what is the test for gram positive
A
crystal violet dye
12
Q
Pink
A
negative
13
Q
purple
A
positive
14
Q
endotoxin
A
negative
15
Q
exotoxin
A
positive
16
Q
what does an oncogene do
A
promote cell division
17
Q
what does a tumour suppressor gene do
A
inhibit cell division
18
Q
pyrimidine
A
cytosine, thymine, uracil
19
Q
purine
A
guanine, adenosine
20
Q
transcription
A
RNA polymerase
21
Q
Topoisomerase
A
DNA rotation to help unwinding DNA
22
Q
helicase
A
unzips DNA
23
Q
DNA polymerase –
A
Adds nucleotides
24
Q
Primase
A
Makes primer DNA
25
ligase
joins up Okazaki fragments
26
start codon =
AUG
27
what provides energy
GTP
28
what catalyses peptide bond formation between amino acids in P and A sites
Peptidyl transferas
29
autosomal dominant
in every generation
50% chance of passing onto offspring
30
autosomal recessive
2 genes needed and even so only a 25% chance of passing onto offspring
31
ectoderm
nervous tissue = controls
32
mesoderm
muscle tissue = moves
33
mesoderm
connective tissue = supports
34
endoderm
epithelial tissue = covers
35
IgM
first
36
IgA
secretory - breast milk
37
IgG
most abundant
38
IgE
allergy
39
high CO2 =
low affinity for O2
40
stroke volume
volume of blood each
ventricle ejects per heart beat
41
cardiac output
volume of blood pumped by each ventricle per minute
CO = SV x HR
42
MAP =
average arterial blood pressure during a single cardiac cycle. [70-105mm Hg]
43
Short term BP change:
When high blood pressure, firing rate to brain increases. Results in vessel dilation + HR falls.
44
Long term BP change: ACE
1. RAAS – Renin stimulates Angiotensin 1 → Angiotensin 2 [produces aldosterone – vasoconstriction → increases SVR]
2. NPs – counters RAAS
a. ANP – atrial distension
b. BNP – ventricles
3. ADH – regulates ECF – increases reabsorption of water, increasing MAP
45
Disaccharide =
Sucrose, Lactose
46
Polysaccharide =
Glycogen, Cellulose
47
∆G =
(energy products) – (energy reactants)
48
what is ∆G linked to
point of equilibrium
49
Primary protein =
Amino acids held together by peptide bonds
50
2nd protein =
Hydrogen bonds
51
3rd protein =
Amino acids interact [3D structure]
52
4th protein =
Disulphide bonds [multiple subunits]
53
Connective tissue –
Collagen triple helix
54
Phosphodiester bond
3’ OH group --- 5’ triphosphate
55
mRNA “messenger”
Carries genetic information for protein synthesis – [Transcription]
56
trna: “transfer”
Carries amino acid to ribosome – [Translation]
57
how many types of eukaryotic cells are there
3 types
58
what are the 3 types of eukaryotic cells
Pol I, II (mRNA), III
59
how many types of prokaryotic cells are there
1 type
60
describe transcription
1. RNA polymerase binding – finds promoters [initiation sites]
2. DNA chain separation – Helicase
3. Transcription initiation – 1st nucleotide added
4. Elongation – Further nucleotides added to RNA chain
5. Termination
61
what provides energy for translation
GTP
62
describe the process of translation
1. Initiator tRNA located at A site – binds to start codon
2. Elongation factor brings aminoacyl-tRNA to A site
3. Peptidyl transferase catalyses bond formation between amino acids in P & A site 4. Termination when A site encounters stop codon
63
degenerate
amino acid with more than one codon
64
unambiguous
codon codes for one amino acid only
65
Apoenzyme =
enzyme, no cofactor
66
Halo-enzyme =
enzyme + cofactor
67
what happens to all enzymes in TCA
they are in matrix but succinate dehydrogenase at the inner mitochondrial membrane
68
mitosis
Diploid parent → 2 diploid daughter cells
69
meiosis
Diploid parent → 4 haploid daughter cells
70
Gene sequence variations due to:
Promoter sequence changes
71
Polymorphisms –
predispose to a disease
72
Mendelion –
single gene mutation = disease
73
Multifactorial –
multiple polymorphisms = risk of disease
74
aneuploidy:
whole missing/extra chromosome
75
Robertsonian translocation
two acro-centric chromosomes stuck end-end [trisomy]
76
Microarray CGH –
1st line chromosome test, detects abnormal chromosomes
77
FISH –
maps genetic material in a person’s cells (visualise specific genes)
78
PCR –
amplifies small piece of human genome [to find mutation]
79
Mosaicism –
having two genetically different types of cells in body
80
Penetrance –
likelihood of having a disease
81
Expression –
variation in disease severity
82
Autosomal dominant:
50% risk child affected
83
Autosomal recessive:
two faulty copies required, 25% risk, incest increases likelihood
84
x-linked:
recessive, only mum → child (50% risk), example – Haemophilia
85
Mitochondrial inheritance:
maternal only
86
Heteroplasmy –
daughter cells contain different proportions of mutant mitochondria
87
what genes are involves in cancer
Oncogenes [ras, PDGF, src]
- Tumour suppressor genes [p53]
- DNA repair genes
- Drug metabolism – genes that metabolise carcinogens
88
what is the breast cancer gene
BRCA1
89
Variolation –
Exposure to dried smallpox pustules from an infected patient
