exam Flashcards
somatic and germline differences
somatic: occurs in body cells
not inheritable
germline: occurs in reproduced cells
inheritable
4 ways antibodies can act
causes particles to clump together- agglutination
coat bacteria so more easily consumed by phagocytes
dissolve organisms
bind to the surface of viruses and prevent them from entering cells
how does the PH of blood alter
CO2 is a product of so respiration
Carbon dioxide combines in water to form carbonic acid which dissociates to form HCO3 irons and hydrogen irons.
as hydrogen ion concentration in the blood increases blood ph decreases
stimulates aortic and carotid bodies
sickle cell symptoms
fatigue, thirst , joint pain,
gene and chromosomal mutations differences
gene - changes in a single gene so that the traits normally produce by that gene are changed or destroyed
chromosome- all part of a chromosome is affected.
gene therapy good for
Cystic fibrosis
Huntington’s disease
sickle cell Armenia
type 1 diabetes
difference in diabtetes 1 and 2
1: childhood - the destruction of beta cells in the islets of Langerhans. Beta cells produce insulin therefore a person with type one diabetes does not produce insulin
2: adult- cells do not respond to insulin.
affects- kidney failure, stroke, heart attack
hyperthyroidism and hypothroidism symptoms
hyperthyroidism- rapid heartbeat, weight loss, increased appetite, fatigue, sweating, anxiety protruding eyeballs
hypothroidism- slow heart rate, weight gain, fatigue lack of energy, swelling of the face and qoitre
Two advantages and one disadvantage of mitochondrial DNA to DNA
Advantage, lots of mitochondria equals lots of DNA, higher mutation rate.
disadvantage- male side - father
vaccines have in common
Weakened virulence by chemicals
Provide memory cells
given before catching the disease
artificial
active
can be injected
living attenuated
Micro organisms with ability to produce disease symptoms. Therefore the immunised person does not contract the disease but manufacture of antibodies against the antigens
Examples are polio + measles
-last longer
Provide a stronger immune response
inactivated vaccine
Contain dead micro organisms. Produce immunities should’ve lost and then immunisation using living attenuating micro organisms. Whooping cough
toxiod
Toxins produced by the bacteria can be activated so that when injected into someone and you do not make the person feel such as ill. called toxoids. Tetanus
Sub unit vaccine
Fragment of the organism can be used to provide to him in response. Hepatitis B.
homo neanderthal vs sapiens
neanderthal - short stocky
no chin
occipital bun
mousterian
sapiens
no occipital bun
in present
taller thin
aurignacian
thalassima b
Beta thalassaemia is due to a mutation in the HBB gene on chromosome 11 this reduces the level of beta Globin in the haemoglobin.
\More prevalent in the Mediterranean basin
thalessima A
Alpha thalassaemia is due to mutation in the HBA on chroma zone 16 this reduces the level of alpha Globin in haemoglobin
More prevalent in South East Asia
What is thalassaemia
An autosomal recessive gene that alters the structure of haemoglobin which therefore means the victims cannot carry as much oxygen in the blood
what is tay sachs
Lethal condition caused by mutation that results in the absence of enzyme better hexominisades
Leads to the deterioration of the nervous system and death usually occurs at a young age
People who are heterozygous have a reduced amount of better hexominisades which provides them protection from tuberculosis.
genetic drift
The random, non-directional changes in a little frequency between generations. Purely by chance is it Cousin populations of all sizes.
founder effects and what it causes new groups to have
When a small group moves away from its homeland to a totally new area and establishes a population.
It will have a different a low frequency from the original population.
It will decrease genetic variation.
Bottle neck
Extreme example of genetic drift wet situations such as a natural disaster severely reduces the size of the population.
Speciation steps 4
Variation – a population exists on an island
Isolation the species is divided into two populations which gives them different gene pools
Selection – two subspecies begin to form this is due to different selection pressures and brings change engine frequencies
Speciation – two species now exist as jeans pink which is maybe great enough to prevent production of photo offspring but interbreeding in between the two populations.
pcr steps
Polymerase chain reaction mimics the process of DNA replication
Denaturation - two strands of DNA are separated and proper proximately 94 to 96°C this breaks the hydrogen bonds holding this two strands together
Annealing – temperature decrease to 50 to 60°C and short sections of DNA primers are bound to separate strands and a complimentary to the DNA being copied
Extension – the enzyme DNA polymerase is used to join you complimentary nucleotides to the originating sections with partners this happens in around 68 to 72°C.
9 adaptations hominid for erect posture
Foreman magnum – located centrally in the base of the cranium
Jawbone – small and non-protruding, enabling the skull to balance on the veterbral column
Vertebral column – lumbar vertebrae wedge shaped, producing S shaped curve that brings vertebral column directly under the centre of the skull.
Pelvis – broad; shallow from top to bottom. Provide support for abdominal organs. Attachment of famous is wide apart contributing to the carry angle
femur - large head of femur contribute to carrying angle
Knee joint – outer hinge larger and stronger, to take weight of body knee is able to be straightened
Legs – longer than arms, contributing to low centre of gravity. Carrying angle allows the weight of the body to be kept close to the central axis
Foot - large heel bone and a line big toe for a pedestal on which the body is supported, foot has both longitudinal and transverse arches
Muscle tone – partial contraction of muscles to support the spine hip knee and ankle
synapse transmission
action potential arrives at pre-synaptic knob/axon endings calcium ions flow into pre-synaptic knob/exocytosis of vesicles containing neurotransmitter
neurotransmitter diffuses across gap/synapse
neurotransmitter binds to receptors on post-synaptic membrane/ dendrite of next neuron
ion channels on the post synaptic membrane open/causes an influx of sodium ions/triggering depolarisation/triggering action potential
8 points Explain how different antibiotics can be used to treat infections
antibiotics target disease-causing bacteria
can be broad spectrum/affect a wide range of bacteria
or can narrow spectrum/effective only against specific types of bacteria (bacteriostatic) antibiotics inhibit the growth of bacteria
by interfering with protein synthesis
(bactericidal) antibiotics destroy bacterial pathogens
by targeting cell walls, cell membranes or
metabolic pathways/action of enzymes found inside bacteria
Describe the physiological mechanisms that cause fever 8 marks
hypothalamus increases thermostat setting of body (person feels cold)
pyrogens released
Produced by white cells or pathogens
muscles begin to shiver
blood vessels constrict
both processes help to drive up body temperature
macrophage engulfed pathogen
macrophage stimulated to release interleukins/cytokines interleukins/cytokines enhance the pyrogens
(a) hGH is released from the pituitary gland. State from which lobe of the pituitary this hormone is secreted and explain the relationship between this section of the pituitary
gland and the hypothalamus. 6 points
secreted from the anterior lobe
communication between the hypothalamus and the anterior pituitary occurs through chemicals/hormones
through the infundibulum/blood vessels
hypothalamus stimulates the anterior pituitary to release hormones via releasing factors/hormones
the hormones are released into a capillary network and transported through veins
also produces inhibiting factors to inhibit activity of the pituitary
Explain how hGH enters and affects the functioning of ts target cell.
6 pints enters and affects
dissolve in water (not fats) so cannot pass through cell membrane hormone molecule attaches to receptor molecule
receptor molecule found on surface of target cell
inding of hormone to receptor triggers a secondary messenger/response inside the cell
secondary messenger activates enzymes inside the cytoplasm
enzymes adjust chemical activity of the cell
Explain how the process of natural selection can lead to a particular phenotype
becoming prevalent in a population
1mark 3 mark 6mark.
variation present in individuals
limited resources available
selection pressure present
competition for resources/struggle to survive
genes passed to offspring
a particular phenotype is more suitable for the environment
individuals that do not possess the phenotype (genes) die-off
individuals that do possess the phenotype (genes) survive/survival of the fittest
over time more individuals have more suitable characteristics
after many generations, the particular phenotype is more prevalent
carbon 14 process 4 marks
Based on the decay of carbon-14 into nitrogen
Amount of carbon-14 is fixed at death
The ratio of carbon-14 to carbon-12 determines the age Carbon-14 has a half-life of 5730 years
