. Flashcards
(79 cards)
1
Q
Hydrolysis
A
Water is used to break down the chemical bonds that exists between a particular substance.
2
Q
Uncertainty
A
Amount of error your measurements might contain
3
Q
Steroids
A
Lipids, hydrophobic and soluble in water.
4
Q
Triglyceride
A
Type of lipid, three fatty acids attached to a glycerol backbone. Major form of energy storage and used for insulation and protection of organs
5
Q
Water potential
A
Pressure exerted by water molecules on a membrane (kPa)
6
Q
Isotonic solution
A
No net movement of water particles. Cell membrane is attached to a cell wall
7
Q
Hypertonic solution
A
Water particles move out of the cell. Cell membrane shrinks and detaches from the cell wall
8
Q
Hypotonic solution
A
Water particles move out of the cell. Cell counteracts osmotic pressure to prevent swelling and lysis
9
Q
Sunken stomata
A
Prevent water loss
10
Q
Exocytosis
A
Secretion from the cell, vesicle containing molecules of substances fuses with the inside of the cell membrane and the molecules are secreted form the cell
11
Q
Endocytosis
A
Process of capturing a substance or particle from outside the cell by engulfing it with the cell membrane, and bringing it into the cell
12
Q
Pinocytosis
A
Where fluid and dissolved substances and molecules are taken up by the cell.
13
Q
Phagocytosis
A
Cells can engulf pathogens or cells and internalise them.
14
Q
Lymph
A
Clear fluid that contains immune cells and waste products, instead of blood. Delivers proteins and nutrients to your blood and helping to dispose of dangerous substances
15
Q
Purines
A
Adenine and guanine
Two carbon nitrogen rings bases
16
Q
Pyrimidines
A
Cytosine and thymine
One carbon nitrogen ring bases
17
Q
What is a gene?
A
A sequence of dna (nucleotide) bases that codes for:
- amino acid sequence of a polypeptide
- a functional RNA (eg. Ribosomal RNA or tRNA)
18
Q
What is a chromosome?
A
- long, linear DNA + it’s associated his tone proteins
- in the nucleus of eukaryotic
19
Q
Methylation
A
Regions with low or no transcriptional activity are densely packed
20
Q
Acetylation
A
Regions with high transcriptional activity are loosely packed. Transcription factors can bind the DNA and genes are expressed
21
Q
B- lymphocyte
A
Involved in the humoral response and procure antibodies specific to the antigen. Antibodies bind to antigens and causes the virus to clump together/ agglutinate
22
Q
T- lymphocyte
A
Involved in the cell mediated response and are involved in producing t-helper cells and t killer cells
23
Q
Genome
A
the haploid set of chromosomes in a gamete or microorganism, or in each cell of a multicellular organism.
24
Q
Glycoprotein
A
A molecule that consists of a carbohydrate plus a protein
25
Zitwerrion of amino acid.
The term zwitterion is used for a molecule that carries both the positive and negative charges and thus, is electrically neutral. As mentioned earlier, all amino acids carry a weak acidic group and a weak basic group. At the physiological pH of the human body, the carboxylic group of amino acids easily donates its proton that is immediately accepted by its amino group.
Thus, at the physiological pH, the carboxylic group of amino acids is ‘deprotonated’ and carries a negative charge, while the amino group is ‘protonated’ and carries a positive charge. Both the negative and the positive charges cancel out each other, resulting in a neutral amino acid that behaves as a zwitterion.
26
Pollination
Process of transferring the male gametes (pollen grains) in plants from the male reproductive part (anther) to the female reproductive part (stigma)
27
Advantages of cross pollination
-increase variation in the population
-ensures inbreeding occurs
-widens the gene pool
-increase number of variants for natural selection
28
Disadvantages of cross pollination
-needs another plant in nearby area
-need pollinating agent
-waste of energy/gametes/pollen
-takes longer and generates fewer offspring
29
Germination
Process by which a seed emerges from a period of dormancy and begins to sprout. It involves the growth and development of the embryo root and embryo shoot.
30
Germination
Process by which a seed emerges from a period of dormancy and begins to sprout. It involves the growth and development of the embryo root and embryo shoot
31
Spermatids
Non- motile haploid cells after meiosis two
32
Spermatozoa
Haploid functional gametes, capacitated to form motile sperm
33
Accessory cells in spermatogenesis
Sertoli cells, secrete fluid into the lumen of seminiferous tubule
34
Leydig cells in testis
Have an endocrine action as they produce and secrete hormone- testosterone
35
When does crossing over occur in spermatogenesis
Only in primary spermatocyte
36
Bacteriocidal antibiotics
Kill the bacteria by either preventing cell wall synthesis or by disrupting protein synthesis in batería.
37
Bacteriostatic antibiotics
Prevent the growth and reproduction if bacteria, but do not kill them. Eg, tetracycline
38
Disease
Malfunction of the body or mind, which adversely affects the health of the individual
39
Virulence
Ability of a pathogen to cause a disease
40
Retrovirus
Genetic information is in the form of RNA not DNA
41
Gram negative bacteria
-stains pink
-thinner peptidoglycan cell wall
-outer lipopolysaccharide envelope
42
Gram positive bacteria
-stains purple
-thick peptidoglycan cell wall
-no outer envelope
43
How to do a gram stain
-prepared bacterial slides are stained with crystal violet for 30 seconds before washing briefly with water
-the slide is then flooded with grams iodine to bring the crystal violet-iodine complex to the peptidoglycan wall
-after one minute the slide is rinsed with water followed by alternate washes of 95% alcohol and water for 30 seconds until no further colour loss can be seen
-a counter stain is now used to colour any of the cells that have none of the crystal violet colour left after the washing. A counter stain such as safranin is added and left for 30 seconds. This stains any cells that have not refrained the crystal violet
-the slide is then blotted, dried and observed under the microscope. The differences in colour will determine wether gram-negative or gram-positive bacteria are present
44
Bacterial cell morphology- cocci, bacilli, spirilla
Cocci- spherical shape
Bacilli- rod shaped
Spirilla- corkscrew shape
45
Herd immunity
Describes how many people in a population have immunity to that pathogen. If herd immunity is high, epidemics are less likely to happen as someone with the disease is more likely to encounter people who are already immuned
46
Defence mechanisms- non-specific responses
-Barriers, skin, conjunctiva, ciliates epithelial lining of the airways, stomach lining
-inflammation, mast cells release compounds- histamine
-phagocytosis
47
Defence mechanisms- specific responses
-cell mediated response using T lymphocytes
-humoural response using antibodies
48
Phagocytosis
Phagocytosis cells- neutrophils
-pathogens release chemicals and the damaged cells release cytokines- attracting phagocytes
-pathogen becomes attached to receptors on the cell surface membrane of the phagocyte either directly or by linking molecules- opsonins
-phagocytes surround the pathogen with a phagosome
-lysosomes containing hydrolytic enzymes fuse with the phagosome, harmless products are released in the cytoplasm
49
Clonal selection
-dendritic cell comes into contact with antigen from foreign pathogen
-binds to the pathogen and expresses the antigen on its csm
-travels through the lymphatic system to the lymph nodes where the b and T cells have gathered
-t cells pick up the antigen and divide to form t helper cells
-t helper cells divide to create and activate: t killer cells, monocytes, b helper cells or b memory cells
-b helper cells can differentiate to produce plasma cells that secrete antibodies against the pathogens antigens
-b helper cells can also differentiate into memory cells so that the immune response reacts quicker if the pathogen is to occur again
50
Antibodies structure:
Soluble glycoproteins
-constant region
-variable region, unique antigen binding site
51
How do antibodies destroy pathogens:
-agglutination, clump bacterial cells together
-precipitation of soluble antigens
-lysis, attract proteins to destroy cells
-neutralisation of the toxins
-opsonins
52
Active immunity
Natural- antibody production following infection
Artificial- vaccine of weakened/died pathogens trigger an immune response
53
Passive immunity
Natural- maternal antibodies pass along the placenta or in breast milk
Artificial- injection of antibodies for temporary immunity
54
Locus
Position of a gene on a chromosome
55
Genotype
Genetic constitution of an organism
56
Phenotype
Expression of genetic constitution and interaction with the environment
57
Allele
Version of a gene
58
Gene
Length of dna on a chromosome that code for the production of. One or more polypeptide chains and functional rna
59
Short term changes to circulatory and respiratory system
-heart rate to increase
-vasodilation of arterioles in the skeletal muscle
-increased blood flow to active muscles
-increase in stroke volume
-reduced blood flow to the digestive system
-vasodilation to the arterioles supplying the surface of the skin
-incr breathing rate and depth of breathing
60
Long term effects of exercise
-incr vo2 max and stroke volume
-incr heart size
-decr heart rate
-incr in no and size of mitochondria in the myocytes
61
Indirect measurement of vo2 max
Bruce treadmill test
-multilevel treadmill test
-can check nerve impulses from SAN in patients with suspected CHD
62
Direct measurement of vo2 max
Gas analysers
-measure respired gases
-more accurate and specific data
63
Environmental factors that can affect vo2 max
Temperature- as decr solubility of gas incr- incr vo2 max
Altitude- po2 decreases as altitude increases- decr vo2 max
64
Effects of lactic acid
-dissociates to form lactate and proton
-accumulation of protons, ph falls, acidic environment
-decr in pH, stops glycolysis
-also stops lactate pathway, prevents atp production, cell and tissue death
65
Cori cycle
-lactate is transported from skeletal muscles to hepatocytes
-lactate broken down in the presence of O2 to pyruvate, using lactate dehydrogenase
-LDH uses the protons removed from lactate to reduced a molecule of NAD to red NAD
-pyruvate then enters the mitochondria via a carrier protein for either:
Route 1 or route 2
66
Route 1 of cori cycle:
-Pyruvate may be converted to CO2 and acetyl coenzyme A using pyruvate dehydrogenase
-aCoA then enters the kerbs cycle- production more ATP
-liver turns lactic acid into glucose- gluconeogenesis
67
Route 2 of Cori cycle:
-when lactic acid is abundant in the liver cells after exercise
-pyruvate carboxylate adds a a molecule of bicarbonate to pyruvate, then converted to oxaloacetate
-reaction requires an energy input in the form of a molecule of atp
-OAA is then converted back to glucose inside the cell through a series of enzyme-chemical reactions
68
Oxygen defecit definition
Difference between the oxygen demand of the active muscles and the oxygen the active muscles actually recieve is. Called the oxygen deficit
69
EPOC definition - oxygen debt
Increased use of oxygen consumed after vigorous exercise
70
Formula to calculate epoc
Tidal volume of O2 consumed during recovery period- tidal volume of o2 consumed at rest = EPOC
71
Tidal volume definition
the amount of air that moves in or out of the lungs with each respiratory cycle
72
Association
Binding of an oxygen molecule to 1 harm group to form oxyheamoglobin
73
Dissociation
Release of an oxygen molecule from 1 harm group within oxyhb
74
Dissociation curve
Relationship between partial pressure of O2 and the saturation of the respiratory pigment
75
Partial pressure calculation
Volume of specific gas/ volume of all gases = pressure of specific gas/ pressure of all gases
76
What does the Bohr shift promote
The release of oxygen from oxyhameoglobin
-lower partial pressure of oxygen as more co2 present
-oxyhb molecules pick up protons, forming haemoglobonic acid, promoting the release of oxygen
77
Types of gene mutations - change in one or more DNA bases
-substitution
-insertion
-deletion
78
Type of chromosome mutations- mutation of genetic material
-duplication
-deletion
-inversion
-translocation
79
Pollutants
Substances released into the environment which can harm organisms or environment itself
