Module 2 Flashcards
1
Q
Centrioles
A
Structures found in cytoplasm made of microtubules that produce the spindle fibres during mitosis
2
Q
Chloroplast
A
Organelles found in plants and algae which are site of photosynthesis
3
Q
Cilia
A
Small hair like structures, projecting from cell surface
4
Q
Confocal microscopy
A
Microscopy which uses lasers to scan a specimen point to point to produce an image
5
Q
Cytoskeleton
A
A mesh of protein fibres found in the cytoplasm of eukaryotic cells used for structural support and intracellular transport
6
Q
Differential staining
A
Multiple different stains to distinguish different parts of specimen
7
Q
Eukaryotic cell
A
Cell with a nucleus and membrane bound organelles
8
Q
Flagella
A
Whip like structure found on bacterial cells used for cell movement
9
Q
Golgi apparatus
A
Found in eukaryotic cells involved in modifying and packaging proteins
10
Q
Light microscope
A
Microscope which uses a series of lenses to magnify visible light reflecting off a specimen
11
Q
Lysosomes
A
Membrane bound vesicles found in cytoplasm that contain the hydrolytic enzyme called lysozyme
12
Q
Magnification
A
How much bigger an image appears compared to an original object calculated using the formula
Image size = actual size x magnification
13
Q
Mitochondria
A
Organelle found in eukaryotic cell which is site of aerobic respiration
14
Q
Nuclear envelope
A
Double membrane surrounding the nucleus
15
Q
Nucleolus
A
Structure in nucleus that contains proteins and RNA and is involved in synthesising new ribosomes
16
Q
Nucleus
A
Organelle found in eukaryotic cells that store as genetic information of cell as chromosomes and surrounded by nuclear envelope
17
Q
Plasma membrane
A
A semipermeable lipid bilayer studded with proteins which surround cells
18
Q
Prokaryotic cell
A
A type of cell which doesn’t contain membrane bound organelles or nucleus
19
Q
Resolution
A
Ability to distinguish between two points in a specimen
20
Q
Ribosomes
A
Organelles free in cytoplasm or membrane bound which are involved in synthesis of proteins
21
Q
Rough endoplasmic reticulum
A
Membrane bound organelle involved in synthesis and packaging of proteins
22
Q
Scanning electron microscope
A
Microscope which passes a beam of electrons over the surface of a specimen to produce an image
23
Q
Smooth endoplasmic reticulum
A
Membrane bound organelle involved in lipid synthesis
24
Q
Transmission electron microscope
A
Microscope with passes a beam of electrons through a sample to produce an image
25
Adhesion
Properties of water molecules which creates an attraction between them and surfaces they are in contact with
26
What is an amino acid
Monomers containing an amino group, carbonyl group and a variable r group
27
Amylopectin
Branched polysaccharide made up of alpha glucose monomers joined by alpha 1-6 glycosidic
28
Anions
Ion with negative charge
29
Benedicts test
Biochemical test used to detect presence of reducing sugar in solution
30
Biuret test
Purple collar when added to solution containing protein
31
Cellulose
Linear polysaccharide that is the main component of the cell wall in plants and made up of many beta glucose molecules joined by beta 1-4 glycosidic bonds
32
Cations
Ion with positive charge
33
Cohesion
Property of water molecules that create an attraction between hem which causes them to stick together
34
Condensation reaction
Reaction that joins two molecules together with the formation of a chemical bonds involving the elimination of a molecule of water
35
Conjugated protein
Protein with a prosthetic group bound to it
36
Elastin
Type of a fibrous protein that allows tissues and structures like blood vessels to stretch and return to original shape
37
Fibrous protein
Class of long chain proteins that are insoluble in water and have structural roles
38
Globular protein
Spherical shaped proteins that are generally water soluble and typically have metabolic roles
39
Glucose
Hexose monosaccharide that is the main respiratory substrate in eukaryotes
40
Glycogen
Highly branched polysaccharide that is used as a main energy storage molecule in animals and is made of alpha glucose monomers joined by a 1-4 glycosidic bonds
41
Haemoglobin
A type of conjugated globular protein used to transport oxygen that is made up of four polypeptide chains each containing a haem prosthetic group
42
Hexose monosaccharide
Simple sugar containing 6 carbon atoms
43
Hydrogen bonds
A weak bond formed between an electropositive hydrogen and and an electronegative atom e.g. o2 and nitrogen
44
Hydrolysis
Breaking a chemical bond between two molecules involving use of a water molecule
45
Insulin
Globular protein hormone that is made in the pancreas in response to detection of high glucose levels in the blood
46
Iodine test
Test that produces a blue/black color when added to a starch containing solution
47
Keratin
A fibrous protein that provides strength to hair and nails
48
Lactose
A disaccharide made of a molecule glucose and galactose joined by a glycosidic bond
49
Lipid emulsion
Produces cloudy emulsion when performed on lipids
50
Maltose
Disaccharide made of two molecules off glucose joined by a glycosidic bond
51
Pentose monosaccharide
Simple sugar with 5 carbon atoms
52
Phospholipid
An amphipathic lipid made from a molecule of glycerol bonded to two fatty acid molecules and a phosphate group
53
Primary strucure
Sequence of amino acids in a protein
54
Quaternary structure
Structure applicable to proteins with multi polypeptide chains that describes the interactions of different chains
55
Ribose
A pentose monosaccharide which composes the backbone of RNA
56
Saturated fatty acid
Fatty acid molecule with only single bonds between carbon atoms
57
Secondary structure
Local interactions of amino acids in polypeptide chain
58
Solvent
Lipid that solutes can dissolve in to form a solution
59
Starch
Polysaccharide used for energy storage in plants that is made up of alpha glucose joined together in forms of amylose and amylopectin
60
Sucrose
Disaccharide made up of a molecule glucose and fructose joined by glycosidic bond
61
Tertiary structure
Way protein folds to make a 3d structure
62
Triglyceride
Type of lipid formed from a molecule of glycerol joined by ester bonds to three fatty acid molecules
63
Unsaturated fatty acid
Fatty acid molecule containing at least one double bond in carbon chain
64
ATP
A nucleotide consisting of ribose molecule joined to nitrogenous base adenine and three phosphate groups
65
Degenerate
Some amino acids can be coded for by different codons
66
DNA
Double stranded polynucleotide that contains the genetic material of an organism and made of deoxyribonucleotide monomers joined together by phosphodiester bonds
67
DNA nucleotide
Monomer which makes up DNA and consists deoxyribose, nitrogen base and phosphate groups
68
DNA polymerase
Enzyme which catalyses the formation of phosphodiester bonds between nucleotides and synthesis of new DNA strand
69
RNA polymerase
Enzyme catalyses the formation of phosphodiester bonds between nucleotides during the synthesis of new RNA strand
70
Helicase
An enzyme which catalyses the unwinding and unzipping of DNA in many processes e.g. replication and transcription
71
mRNA
RNA which carries genetic info from the DNA in the nucleus to ribosomes for translation
72
Phosphodiester bond
Bond which joined nucleotides together to create polynucleotides
73
Purines
Nitrogenous bases which are made up of two rings - adenine and guanine
74
Pyramidines
Nitrogenous bases made up of a single - Cytosine, thymine and uracil
75
Ribosomal RNA
RNA which makes up ribosomes
76
Semi-conservative replication
Replication of DNA to make two new DNA molecules which both contain one new strand and one old from the original
77
Transcription
Synthesising a new mRNA strand from a molecule of a DNA
78
tRNA
RNA which has three hairpin loops, an anticodon for attachment to mRNA codon and an amino acid binding site and used to carry amino acids to the ribosome
79
Translation
Protein synthesis where complementary tRNAs carrying amino acids are brought to each codon in an mRNA molecules as move through ribsome
80
Activation energy
Amount of energy needed for a reaction to happen
81
Active site
Specific region on an enzyme where the substrate binds and reaction occurs
82
Amylase
An enzyme which catalyses the extracellular breakdown of starch
83
Catalase
Enzyme which catalyses the intracellular breakdown of hydrogen peroxide into oxygen and water
84
Coenzyme
A cofactor which is bound loosely to an enzyme with loose interactions
85
Cofactors
Non protein molecule which is needed for effective functioning of an enzyme
86
Competitive inhibitor
Molecule which binds to active site of an enzyme and prevents the substrate from binding
87
Cyanide (CN-)
A metabolic poison which acts as an irreversible inhibitor of cytochrome oxidase and prevents respiration
88
End product inhibition
Enzyme inhibition where the product of an enzyme controlled reaction can bind to enzyme and prevent it from working
89
Enzyme substrate complex
Temporary complex formed when substrate binds to active site of an enzyme
90
Enzyme
Biological catalyst used to speed the rate of biochemical reactions without being used out or altered permenantly
91
Enzyme product complex
Temporary complex formed after enzyme has catalysed the reaction but before products have left active site
92
Extracellular reaction
Reaction occuring outside cells
93
Inactive precursor
Inactive form of an enzyme that cannot carry out function unless activated
94
Induced fit hypothesis
Model of enzyme action that describes how once a specific substrate binds to active site. Enzyme undertakes subtle conformational changes to fit the substrate better
95
Intracellular reaction
Reaction within cells
96
Lock and Key Hypothesis
Enzyme will only fit substrate that has complementary shape to active site
97
Metabolism
Sum of chemical reactions taking place in cell
98
Non competitive inhibitor
Inhibitor which binds to different part of an enzyme (allosteric site) and prevents function of enzyme
99
Prosthetic group
A cofactor which is bound lightly to an enzyme with strong interactions
100
Substrate specificity
Ability to enzyme to catalyse only a specific reaction or a set of reactions which have substrates complimentary to active site of enzyme
101
Temperature coefficient
Calculation of increase in reaction rate after a 10 degree temp increase
102
Trypsin
An enzyme which catalyses the extracellular breakdown of proteins
103
Active transport
Active movement of substances from a low concentration to a higher concentration with the use of energy from ATP
104
Amphipathic
Molecule with hydrophobic and hydrophillic parts
105
Cell lysis
Bursting of cell usually when uptake of too much water into an animal cell through osmosis
106
Cholestrol
Mostly hydrophobic molecule which sits in hydrophobic portion of membrane and regulates membrane fluiditiy
107
Crenation
Shrinking of cell when placed in a hypertonic solution due to large amounts of water moving out cell due to osmosis
108
Endocytosis
Bulk uptake of substances into the cell invagination of the membrane to form a vesicle trapping the solution inside the cell with the use of energy (ATP)
109
Exocytosis
Bulk transport of substances out of cell using a vesicle that fuses with plasma membrane using ATP
110
Faciliated diffusion
Net movement of substances from a high conc to a low conc through transport proteins without energy
111
Fluid mosaic model
Model which describes membrane structure as sea iof mobile phospholipids studded with proteins
112
Hydrophillic
Molecule attracted to water
113
Hydrophobic
Molecule which repels water
114
Integral membrane protein
Type of membrane bound to membrane with strong interactions
115
Osmosis
Net movement of water molecules across a partially permeable membrane from a region of high water potential to a region of lower water potential without the use of energy
116
Peripheral membrane protein
A protein that is weakly bound to surface of membrane
117
Phagocytosis
Ingestion of solid material by phagocytic cells
118
Phospholipid
Lipid formed by condensation of one molecule of glycerol, two fatty acids and one phosphate group
119
Pinocytosis
Bulk uptake of liquids into cell using energy in the form of ATP
120
Plasmolysis
Effect produced by placing plant cells in a hypertonic solution causing the cell to shrivel from water loss, resulting in membrane pulling away from rigid cell wall
121
Simple diffusion
Spreading out of substances from high conc to a lower conc without use of energy
122
Turgid
A cell which is swollen due to large amount of fluid uptake
123
Water potential
Measure of tendency of water molecules to move to onr strs to another
124
Acrosome
Organelle in the head of sperm cells, which is specialised to digest the outer coating of an egg cell during fertilisation
125
Anaphase
Third stage in mitosis, where chromosomes are pulled apart to poles of cell by spindle fibres
126
Anaphase 1
Third stage in meiosis where chromosomes which make up the bivalent are pulled apart from poles of cell by spindle fibres
127
Anaphase 2
Seventh phase of meiosis where chromatids are pulled apart to opposite poles of the cell
128
Anucleate
Type of cell without a nucleus
129
Asexual reproduction
Production of genetically identical offspring from one parent through mitosis
130
Bivalent
Pair of homologous chromosomes
131
Cilated epithelium
Type of epithelium which has many fine protusions (cilia) and is specialised for sweeping dirt and debris out the body
132
Crossing over
Exchange of genetic material between two chromosmes in a bivalent
133
Cytokenesis
Division of cytoplasm at the end of mitosis to produce two new daughter cells
134
Differentiation
Process where a cell develops certain features so it is specialised to carry out a certain function
135
Diploid
Cells with two copies of each chromosome
136
Erythorcyte
An anucleate cell specialised to carry oxygen from lungs around the body RBC
137
G1 checkpoint
First checkpoint in cell cycle which commits cell to division under favourable conditions
138
G1 phase
First growth phase in interphase where the cell synthesises proteins and dupilicates its organelles and increases in size before DNA replication in S phase
139
G2 checkpoint
Second checkpoint in cell cycle, occurs replication of DNA is correct
140
Gametes
Sex cells which have haploid nucleus and are produced during meiosis
141
Gene loci
Location of gene on chromosome
142
Guard cells
Type of cell usually found in plants that is specialised to control the opening and closing of stomata
143
Haploid
Cells with only one copy of each chromosome
144
Homologous chromosomes
Two chromosomes with similar gene loci but different alleles, one inherited from each parent
145
Independant assortment
A source of variation in meiosis where bivalent chromosomes can line up either way round on metaphase plate
146
Interphase
Largest part of cell cycle where cells spend time growing , synthesising biomolecules and preparing for mitosis
147
Metaphase checkpoint
Checkpoint at end of metaphase, ensures all chromosomes have properly attached to spindle fibres and aligned at metaphase plate
148
Meiosis
Cell division used to produce gametes that produce four genetically different haploid daughter cells
149
Meristematic tissue
Plant tissue which contains stem cells and usually found in growing regions
150
Metaphase
Second stage in mitosis where chromosomes attach to spindle fibres and align at metaphase plate
151
Metaphase 1
Second stage of meiosis where bivalent chromosomes align across metaphase plate and independent assortment occurs
152
Metaphase 2
Sixth stage of meiosis where recombinate chromosomes align on metaphase plate
153
Mitosis
Division of cell to produce two genetically identical cells
154
Multipotent
Stem cell which can differentiate into any type of cell within a certain tissue in body
155
Neutrophil
Type of white blood cell with multi lobed nucleus which is specialised to engulf and destroy pathogens
156
Organ
Group of specialised tissues working together to carry out a specific function
157
Organ system
Group of specialised organs working together to carry out specific function
158
Palisade cell
Type of cell in leaves of plants which contain chloroplasts to carry out photosynthesis
159
Phloem
A tissue found in plants which is specialised for transport of assimilates from their site of production to different parts of plant where they are needed
160
Pluripotent stem cell
Type of stem cell which has ability to differentiate to any type of cell in body
161
Prophase
First mitosis stage, where nuclear envelope breaks down, the centrosomes move to opposite poles of cell, mitotic spindle begins to form and chromosomes condense
162
Prophase 1
First stage of meiosis where the nuclear envelop breaks down, spindle fibres form and chromosomes condense and form bivalents.
163
Prophase 2
5th stage of meiosis where nuclear envelope breaks down, spindle fibres form and chromosomes condense
164
Recombinant chromosomes
Chromosomes produced by crossing over and exchange of genes during metaphase 1
165
Root hair cells
Type of cell that is found in roots of cells which has a large SA and is specialised for the uptake of water and ions from soil
166
S phase
Second stage in cell cycle where DNA in cell is replicated
167
Somatic cells
Any cells that make up an organism excluding sex cell
168
Sperm cell
Male gamete which contains a long tail, an acrosome and lots of mitochondria
169
Squamous epithelium
Epithelium which is only one cell thick and specialised for rapid diffusion
170
Stem cell
Typed of undifferentiated cell which has ability to divide many times and differentiate into many different cell types
171
Stomata
Small openings in the leaves or stem of a plant that can be opened or closed by guard cells in response to varying conditions
172
Telophase
Final stage of mitosis where new nuclear envelopes begin to form around the separated sets of chromosomes
173
Telophase 1
4th stage of meiosis where nuclear envelopes reform around the separated chromosomes and they uncoil
174
Tissue
Group of specialised cells working together to carry out a specific function
175
Totipotent stem cell
Stem cell which can differentiate into any cell in body/placenta
176
Xylem
Tissue in plants specialised for water transport and dissolved minerals up plant
177
Name of covalent bond between two adjacent amino acids in chain of amino acids
Peptide bond
178
Type of reaction to break a peptide bond and what happens
Hydrolysis
Water is added
179
How does an enzyme e.g. Pepsin break down a substrate
The substrate shape is nearly complementary to active site
Substrate enters active site on enzyme
Induced fit forms an ESC
Straining of bonds in substrate forms EPC
Products leave active site
180
Pepstatin acts as a competitive inhibitor of pepsin, what can we conclude about the structure
Similar shape to substrate
Complementary to part of active site
181
Describe how to do an emulsion test for lipids and how a positive result is identified
Mix with ethanol and water and it will go cloudy
182
How might the lipid content of a mycoprotien differ from food that comes from animals
Has less overall lipid
Less saturated fat/lipid
183
Why is the ability of water to act as a solvent important for the survival of organisms
Is a medium for metabolic reactions because it allows ionic compounds to separate
Organisms can absorb minerals and food
184
Property of collagen which makes it a useful component of blood vessel walls
Strength
185
Structure of a collagen molecule
Peptide bonds between amino acids in a polypeptide
Every 3rd amino acid is the same
Coil in a spiral
Three polypeptide chains
H binds between polypeptide chains
No/few hydrophilic r groups on outside of molecule
186
Function of Hb
Transport of 02
187
How does structure of Hb differ to collagen
Haemoglobin is globular, has 4 polypeptide chains and has hydrophonic r groups on inside and hydrophilic on outside
188
How is a peptide bond formed
Between amine group and carboxyl group of another
Through a condensation reaction
189
Ways that physical properties of water allow organisms to survive over a range of temperatures
High latent heat of vapourisation
Evaporation is efficient cooling mechanism
Example of a cooling in living organisms
High SHC
Thermally stable environment for aquatic organisms
Aquatic organism use less energy in temp control
Bio reactions function correctly
Ice less dense than wardr
Ice is a habitat
190
Roles of cholesterol in living organism
Fluidity of phospholipid bilayer
Making bile salts
191
Describe different ways LDLs and HDLs effect formation of atheromas
LDL
Carry cholesterol from liver to tissue, receptors on tissue cells
Raises blood cholesterol
Increases deposition of fats in artery wall
HDL
Carry cholesterol from tissue to liver
Receptors in hepatocytes
Lowers blood cholesterol
Reduce deposition of fats
192
Why are diets with high red meat content associated with high blood cholesterol
Red meat contains lots of saturated fat
Saturated fat associated with increase amounts of LDLS
193
Why does glycogen make a good storage molecule
It’s insoluble so doesn’t effect water potential of cell
Lots of branches for enzyme to attach
Compact
194
Structure of Hb molecule
Chain of amino acids joined by peptide bonds
Alpha helix, small regions of beta pleated sheets, hydrogen bonds
Hydrophilic r groups outside and hydrophonic o inside
4 polypeptide 2 alpha chain 2 beta
1 Haem group per polypeptide
Prosthetic group is Haem
195
Structure of triglyceride molecule
One glycerol and 3 fatty acids and ester bonds
196
Three roles of lipids in living organism
Thermal insulation
Membranes control entry and exit into cells
Waterproofing
197
What is the role of mRNA
Carries genetic information out of nucleus and transfers it to the ribosome for protein synthesis
198
Why are different enzyme involved in different stages of digestive processes
Enzymes are specific as substrates different shapes
Active site and substrate are complimentary for Lock and Key
199
What is the difference between globular and fibrous proteins
Globular:
Ball shaped, forms H binds with water, soluble
Hb carries o2
Contains prosthetic group
Fibrous:
Long chain form H binds with adjacent chains
Insoluble
Collagen firms cross links with molecules
Part of cartilage
200
How does a nucleotide base sequence in a gene synthesise a polypeptide
Transcription
-DNA transcribed in mRNA
-Activated RNA nucleotides line up by complementary base pairing to one template strand
-Catalyses by RNA polymerase
Translation
-mRNA moves to ribosomes
-tRNA molecules bind to mRNA
-anticodons match with codons
-specific amino acid attached to tTRNA
-formation of peptide bind between amino acids
201
Suggest why DEG-contaminated wines with a high ethanol content may result in less
DEG poisoning than contaminated wines with a low ethanol content.
Ethanol competes with DEG
When at a higher conc ethanol is more likely to collide with active site
Less DEG broken down
202
How might structures of enzymes of antartica and non antarctic fish differ
Different amino acid sequences
Different secondary structure
203
Explain the effect of increasing the concentration of substrate on the rate of reaction;
(i) without inhibitor
More substrate molecules enter active site
More ESC's formed
At low conc not all active sites occupied
At a higher conc- max turnover rate
204
