Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

yr 1 uni work > 112 > Flashcards

112 Flashcards

1
Q

define prokaryotic cell

A

Most abundant type of cell on earth
Do not have membrane bound nucleus
Divided into 2 domains; bacteria and archaea

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

where do archaea live

A

very extreme conditions usually

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

shapes of bacteria

A

cocci- spherical
bacilli- rod
spirochetes- helical

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what protein is in prokaryote flagella

A

flagellin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what are prokaryotic pili composed of

A

protein pilin and help bacteria stick to their substrate or to each other

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what domain contains nuclear envelope

A

eukarya

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what domain contains membane-enclosed organelles

A

eukarya

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what domain contains peptidoglycan in cell wall

A

bacteria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

whats the inititator amino acid for protein synthesis in bacteria

A

Formyl-methionine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

bacteria’s response to the antibiotics streptomycin and chloramphenicol

A

growth is inhibited

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

do bacteria have histones associated with DNA

A

absent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Gram + peptidoglycan layer

A

thick

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

gram - peptidoglycan layer

A

thin layer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

gram + cell wall structure

A

simple, single layer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

gram - cell wall structure

A

complex, double layer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

gram + teichoic acid

A

present

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

gram - teichoic acids

A

absent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

gram + lipopolysaccharide

A

absent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

gram - lipopolysaccharide

A

present

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

gram +, gram stain

A

purple

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

gram -, gram stain

A

pink

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

gram + antibiotic resistance

A

susceptible

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

gram - antibiotic resistant

A

resistant

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

gram - examples

A

chlamydia trachomatis
yersinia pestis
vibrio cholerae

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

gram + examples

A

clostridium tetani
clostridium botulinum
streptococcus pnuemoniae

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

medical uses of bacteria

A

produce large quantities of proteins cheaply for therapeutic use for example insulin
drug screening tests and diagnostics for example beta amyloid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

agricultural uses of bacteria

A

introduction of a new gene in plant chromosome
e.g. purple tomatoes have high anthocyanin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

environmental uses of bacteria

A

bioremediation- removes pollutants, industrial by-products, oil spills

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

industrial uses of bacteria

A

lactic bacteria develop the flavour and colour of foodstuff
improve the storage longevity of wines

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

photoautotrophs

A

photosynthesis organisms which us light to synthesize organic compounds from carbon dioxide

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

chemoautotrophs

A

use carbon dioxide as a carbon source and obtain their energy by oxidising inorganic substances e.g. from hydrogen sulphide. This mode is unique to certain prokaryotes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

photoheterotrophs

A

use light to generate ATP but must obtain their carbon in an organic form, this type is unique to certain prokaryotes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

chemoheterotrophs

A

use organic molecules to supply both carbon and energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

can viruses self repair

A

no

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

do viruses have an energy transduction system

A

no

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

how can you view viruses

A

only visible with the electron microscope

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

are viruses alive

A

no

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

virion

A

each complete viral particle is called a virion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

capsid

A

protein coat- made up of proteins called capsomers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

filamentous viruses

A

The nucleic acid is arranged in a helix , with the protein sub-units surrounding and stabilizing it. An example is Tobacco mosaic virus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

spheroid viruses

A

The nucleic acid is condensed inside a protein envelope which is usually organized into a multisided geometric shape. An example are adenovirus different types cause illness ranging from Gastroenteritis to keratoconjunctivitis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

tailed spheroid virus

A

This is basically a spheroid virus with a tail. An example is the lambda phage
Enveloped viruses
Have lipid envelopes includes the influenza and coronaviruses viruses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

resolution

A

measure of the minimum distance of 2 distinguishable points

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

contrast

A

visible difference in brightness or colour between parts of the sample

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

how to improve resolution

A

use a shorter wavelength radiation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

advanced light microscopy

A
  • permits observation of transparent living cells
    -light phases shifts induced by specimen are used to generate contrast
    -phase contrast ( refracted and unrefrected light)
    -differential interference contrast ( 2 light beams )
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

fluorescence microscope

A

-shows location of specific molecules in the cell
-fluorescent substances absorb short-wavelength, ultraviolet radiation and emit longer-wavelength, visible light

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

phase contrast microscopy

A

enhances contrast in unstained cells by amplifying in density within specimen- usually useful for examining living unpigmented cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

differential-interference-contrast (nomarski) microscopy

A

like phase-contrast- uses optical modification to exaggerate difference in density

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

confocal microscopy

A

uses lasers and special optics for ‘optical sectioning’
only those regions within a narrow depth of focus are imaged
regions above and below the selected plane of view appear black rather than blurry.
usually used with fluorescently stained specimens

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

transmission microscope

A

electron gun- tungsten filament
beam passes through specimen
focused and magnified by magnetic objective and projector lenses
visible image by a fluorescent screen
photographs taken using digital camera
high vacuum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

scanning microscope

A

electrons scanned across specimen
electrons reflected and collected by electron detector and converted into an electronic signal which is displayed on a screen
gives 3D appearance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

transmission preparation

A

-Whole mounts: Bacteria and viruses can be examined directly Tissue sections
-Fixation: Usually in Glutaraldehyde (protein crosslinking) followed by a second fixation step in Osmium Tetroxide (lipid crosslinking)
-Dehydration: In an ethanol series
-Embedding: Specimens for TEM are embedded in plastic resins such as Epoxy resins.
-Sectioning: 50nm thick sections are cut using a ultramicrotome.
-Staining: Biological tissue has little contrast under the electron beam, so heavy metal stains such as lead are used to improve contrast

54
Q

scanning preparation

A

-Biological samples must be fixed and dried before being examined in the SEM under vacuum
-Fixation: The same fixatives are used as with TEM preparation
-Dehydration: The water is replaced with Ethanol
-Critical Point Drying: This technique allows all of the ethanol to be removed from the sample in a way that minimises shrinkage
-Coating Specimens are coated with a thin layer of gold to protect them from electron beam damage

55
Q

nucleus

A

Largest organelle, contains most genes which control cell, nuclear membrane encloses the nucleus separating it from the cytoplasm which is doubled membraned and contain pores about 100nm in diameter, within nucleus also have the DNA organised into chromatin

56
Q

plasma membrane overview

A

contains cell- separating the cell from its external environment and controls the entry and exit of nutrients/ waste products
impermeable barrier to most water-soluble molecules

57
Q

how are lipid and protein molecules held together in plasma membrane

A

non-covalent interactions (fluid mosaic)

58
Q

Lipids are amphipathic molecules which will spontaneously form bilayers in an aqueous environment- true or false

A

true

59
Q

if damaged the lipid bilayer isn’t able to repair itself- true or false

A

false- it can repair itself

60
Q

lipids constitute about half of the mas of biological membranes - true or false

A

true

61
Q

3 major types of lipids in cell membrane

A

phospholipids
cholesterol
glycolipids

62
Q

what does cholesterol in plasma membrane do

A

increase stability of membrane
at warm temperatures it restrains movement of phospholipids
without it PM cannot function properly

63
Q

freeze fracture electron microscopy

A

observes the shape and distribution of proteins
studies the PM supported the fluid mosaic model
is a specialised preparation technique that splits a membrane along the middle of the phospholipid bilayer

64
Q

receptor sites

A

the exterior region of transmembrane protein may act as a receptor for chemical messenger such as a hormone or growth factor

65
Q

structural roles of membrane proteins

A

membrane proteins called integrins allow the cell to attach to the extracellular matrix

66
Q

cystic fibrosis

A

-Caused by a defective chloride ion channel
-Autosomal recessive disease
-Failure of this chloride channel results in build up of viscous mucus within lungs making it hard to breath and prone to infections
-Appears to be ideal disease to treat with gene therapy but progress has been much slower than expected

67
Q

forms of carbohydrates in PM

A

oligo and polysaccharides bound to membrane proteins as glycolipids

68
Q

what % of membrane mass do carbs take up

A

10%

69
Q

whats glycocalyx

A

Glycocalyx consisting of thin layer of carbohydrate is present on the outside of the plasma membrane of most cells

70
Q

The ABO blood types are determined by carbohydrates in the surface of the red blood cells
true or false

A

true

71
Q

Membrane glycoproteins are not involved in infection mechanisms
true or false

A

false
they are involved- e.g. with HIV

72
Q

endocytosis

A

material taken into cell

73
Q

pinocytosis

A

cells pinch their PM to take up extracellular fluid in small vesicles, non specific

74
Q

receptor mediated endocytosis

A

binding of macromolecules to specific cell surface receptors which triggers endocytosis. clatherin is the protein that forms cage-like structures to allow endocytosis

75
Q

clatherin

A

the protein that forms cage-like structures to allow receptor mediated endocytosis

76
Q

what is the endomembrane system composed of

A

nuclear membrane, the endoplasmic reticulum, golgi apparatus and the lysosomes

77
Q

most cells have relatively little SER
true or false

A

true

78
Q

where is SR found

A

in muscle cells

79
Q

SER- functions

A

Phospholipid, fat and steroid manufacture
carbohydrate metabolism
in hepatocytes, breaks down stored glycogen to release glucose
detoxifies lipid- soluble drugs such as barbiturates

80
Q

in SR (sarcoplasmic reticulum) what does the level of calcium regulate

A

muscle contraction in muscle cells

81
Q

SR overview

A

-Network of tubular sacs
-Sequesters calcium ions from cytosol

82
Q

SR leading to muscle contraction

A

-Action potential triggers SR to release ca into cytosol
-Ca ions bind to tropomysin and troponin leading to a conformational change
-Myosin now interacts with actin and the muscle contracts

83
Q

what does the N-terminus contain on ribosomes that are attached to RER

A

contains a signal peptide usually 20-30 amino acids long

84
Q

SRP ?

A

signal recognition particle
it attaches to signal peptide and stops translation in the cytosol
to start translation again the SRP docks to a SRP receptor on the ER membrane

85
Q

hows the RER membrane cleaved of

A

The hydrophobic signal peptide passes through the membrane and loops back through the membrane and is cleaved off . The rest of the peptide passes through the membrane and into the ER lumen
The signal sequence is cleaved off with the enzyme signal peptidase

86
Q

polyribosome

A

an mrna molecule translated simultaneously by several ribosomes in clusters

87
Q

what does golgi apparatus do

A

modifies and sorts proteins,
Golgi also mediates the flow of proteins from the RER to destinations
- Principle modification which occur to proteins
- Essential for their function e.g. mucin produced by glycoproteins with long highly oligosaccharide chains are essential to produce hydrated gel like material

88
Q

default pathway for golgi and stuff

A

= protein synthesis in RER = through the golgi = then to plasma membrane

Some proteins are tagged in golgi for certain destinations, a mannose 6-phosphate receptor then binds these proteins in the trans golgi reticulum and directs transfer to the lysosomes

89
Q

how many hydrolytic enzymes does the lysosomal system have

A
  • Contain 60 hydrolytic enzymes which biodegrade almost all biomolecules (made in RER)
90
Q

where do primary lysosomes originate from

A

trans face of the golgi

91
Q

what happens when lysosomes fuse with target

A

-When lysosomes fuses with a target, H+ pumped into the secondary lysosome to bring down the pH and activate the enzymes
-Lysosomes carry out phagocytosis
-Carry out autolysis during apoptosis

92
Q

what did Yoshinori Ohsumi win

A

The Noble Prize medicine award in 2016 went to Japanese biologist Yoshinori Ohsumi for discoveries on autophagy, the process by which a cell breaks down and recycles content

93
Q

lysosomal storage diseases

A

-Partially degraded insoluble metabolites can accumulate within lysosomes if a particular lysosomal enzymes is defective
-The resulting material results in enlarged lysosomes that compromise cell function in over 50 different lysosomal storage diseases

94
Q

Tays- Sachs disease

A

in Tay hexosaminidase A enzyme deficiency results in the accumulation of the lipid ganglioside, clinical symptoms are due to this ganglioside in nerve cells, death usually occurs by 2-3 years of age

95
Q

outer membrane of mitochondria

A

-Very similar to other eukaryotic membranes
-Major protein component is porin- large aqueous channels

96
Q

inner membrane of mitochondria

A

-Contain 3 membrane complexes
ETC
ATP synthase
Specific transporters of metabolites which vary according to cell/tissue type

97
Q

cristae

A

-Increase membrane surface area energy
-Energy transducing membrane
-Impermeable to most small ions

98
Q

matrix mitochondria

A

-Enzymes which catalyse Krebs cycle and fatty acid oxidation
-Ribosomes
-Mitochondrial DNA

99
Q

Electrons in C-H bonds are higher energy than those in C-O or H-O bonds
true or false

A

true

100
Q

how does cellular respiration release energy to surrounding

A

The reaction releases energy to the surroundings because the electrons lose potential energy when they end up being shared unequally, spending more time near electronegative atoms such as oxygen

101
Q

glycolysis overview

A

During glycolysis each glucose is broken into 2 molecules of pyruvate, pyruvate then enters the mitochondrion, takes place in cytosol and only releases little energy stored in glucose (through substrate level phosphorylation) and most of the energy remains in the 2 pyruvate molecules
ATP produced in 2 steps but also used up at 2 steps
High energy electrons passed onto electron carrier NAD+ to generate NADH

102
Q

where does glycolysis occur

A

cytosol

103
Q

how much ATP produced in glycolysis

A

produced in 2 steps but also used up in 2 steps

104
Q

link reaction overview

A

Pyruvate is transported into the mitochondrial matrix through a transport protein
Looses CO2
NAD+&raquo_space; NADH + H+
Coenzyme A
Produces Acetyl CoA

105
Q

what does link reaction produce

A

acetyl CoA
NADH

106
Q

ETC overview

A

*High energy electrons passed into electron transport chain
*Stepwise extraction of energy from high energy electrons
*Each component of the chain is slightly more electronegative than the previous
*Passed onto oxygen to generate H2O
*FADH2 passes on electrons at slightly lower stage than NADH
*No ATP is made directly
*Energy used to produce a H+ gradient across the inner mitochondrial membrane

107
Q

F0 portion of ATP synthase

A

is a H+ channel

108
Q

F1 portion of ATP synthase is

A

head is site of ATP synthesis

109
Q

what does movement of H+ through F0 cause

A
  • causes rotation of the rotor and central stalk, while the stator keeps the enzymatic F1 stationary
  • forces sequential conformational changes in the central stalk and F1
  • provides the energy for ATP synthesis
110
Q

in ATP synthase how many ATP molecules are generated from 10H+ moving back into matrix

A

around 3

111
Q

cyanide as a mitochondrial poisen

A

prevents the passage of electrons from one of the cytochromes thereby blocking the ETC, might be fastest poison known to man

112
Q

DNP (2,4-dinitrophenol) as mitochondrial poison

A

make inner membrane leaky to H+ so that a gradient cannot be established for the ATP synthase , ETC still works but energy is released as heat- essential burning victim alive from inside out

113
Q

MERRF- myoclonic epilepsy and aged-red fibre disease

A

genetic- mutation in mitochondrially encoded tRNA Lys gene
affects translation of mitochondrially encoded proteins, abnormal morphology, multisystem disease affecting muscles/nerves (hence the epilepsy)
no cure

114
Q

the cytoskeleton isnt present in every cell
t/f

A

false- it is present in every cell

115
Q

the cytoskeleton has - Important vital functions- muscular movement to transport molecules, normal embryonic development]
t/f

A

true

116
Q

abnormalities in the cytoskeleton dont always lead to disease affecting every tissue in the body
t/f

A

false- can result in disease in every tissue in the body

117
Q

do many current drugs work by targeting the cytoskeleton

A

yes

118
Q

microfilaments

A

about 7nm in diameter and composed of 2 actin chains twisted around each other, have a variety of structural and locomotor functions

119
Q

microtubules

A

straight hollow rods 25nm in diameter and up to 20 microns long, and are constructed from globular proteins called tubulins

120
Q

intermediate filaments

A

8-12nm in diameter and are made up of diverse group of proteins, tend to be permanent fixtures and important in maintaining cell shape and position of certain organelles

121
Q

the 3 components of the cytoskeleton

A

-microfilaments
-microtubules
-intermediate filaments

122
Q

adherens junction

A

cadherins
extracellular - transmembrane
connects cells to actin filaments intracellular signalling regulator

123
Q

focal adhesions

A

connect ECM to actin filaments
integrins

124
Q

desmosomes

A

-Cadherins
-Connect cells to intermediate filaments
-Structural integrity, withstand mechanical stress
-Important in cardiac tissue- interlated discs

125
Q

hemi-desmosomes

A

integrins
connect ECM to intermediate filaments

126
Q

spot-desomosomes

A

-Spot welds together
-Attached on inside of cell to keratin filament, which serve to spread the stresses from the spot desmosome throughout the cell

127
Q

tight junction- 2 functions

A

barrier/gate

fence

128
Q

barrier/gate function in tight junction

A

prevent molecules from leaking between adjacent cells

129
Q

fence function in tight junctions

A

separate the apical plasma membrane from the basal plasma membrane, allowing different compositions
also gives rise to cellular polarity

130
Q
A

yr 1 uni work (13 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions