Short Answer Flashcards
What is an inflammatory response?
An internal non specific defence, it is the response to any damage of the tissues.
Purposes:
1) reduce the spread of any pathogens, to destroy them and prevent the entry of additional pathogens
2) remove damage tissues and cell debris
3) begin repair to damage tissues, this includes redness swelling heat and pain
Homeostasis - what are the strategies to restore high body temperature
The homeostatic response is thermoregulation
What are the processes induced in thermoregulation
thermoregulation includes:
Vasodilation- skin blood vessels increases blood flow through the skin which becomes reddish in colour and surface temperature rises and there is greater heat loss through radiation and convection
Sweating- evaporation of sweat cools body temperature only if the surrounding environment is fairly dry
Metabolic rate- a long term response, a decrease in the metabolic rate, which means less heat is produced in the body. This is the reduction of secretion of thyroxine
Behavioural responses- actions such as turning on a fan or air conditioner, removing external clothing and reducing physical activity.
What is the homeostatic response that causes an increase in respiration rate?
Increased concentration of hydrogen ions. Breathing rate increases because of low oxygen levels. Hyperventilation may occur which is rapid deep breathing.
What are synapses
The junction between the branches of adjacent neutrons. It is a very small gap and mostly occur between the branches of an axon of one neuron and a dendrite or the cell body of another neuron. Messages have to be carried across the synapse. -neurotransmitter receptors at the synapse are couped to a specific channels
What is the result of a strong stimulus
A stimulus is a change in the environment that causes feedback system to operate. Frequency of the action potential.
Cause of natural selection
Mutations in the germ line.
How do bactericidal antibiotics work
Antibiotics are drugs that are used to fight infections of micro-organisms, particularly bacteria. Bactericidal antibiotics kill bacteria by changing the structure of the cell wall or the cell membrane, or by disrupting the actions of essential enzymes.
How does gene therapy work?
It treats or cure genetic abnormalities by replacing faulty genes with healthy ones. It has the potential to correct the underlying cause of the faulty genes by replacing it with healthy ones.
Describe chromosomal mutations: translocation and deletion
Deletion- part of a chromosome is lost
Translocation- part of a chromosome breaks off and is re-joined to the wrong chromosome
Uses of Acheulian tools
Manufactured and used by homo erectus. It is flaked around the edges, first in one direction and then in the other, until they formed roughly two-faced lumps, approx. teardrop in shape.
They are used to process meat and hunting
What is the function of the somatic nervous system
Receiving and sending information as an interaction with the outside environment.
Methods used in the procedure of absolute dating
Tree growth rings (dendrochronology): each of the concentric rings on the surface of a cut tree trunk represent one year’s growth. Each ring differ in width according to how favourable the growing season was. This method can date wood up to 9000 yrs BP.
Carbon 14 or radiocarbon dating: based on decay of the radioactive isotope of carbon, carbon-14, to nitrogen. It is produced in the upper atmosphere by the action of cosmic radiation on nitrogen at the same rate at which it decays. The atmosphere has the ratio of one carbon-14 atom to every millionth of a millionth atoms (10^12) of the stable isotope carbon-12.
It measures the amount of radiation liberated by a sample, the ratio of carbon-14 to carbon-12 can be estimated, and from this age of the sample can be calculated. This method normally requires at least 3 grams of organic material.
Processes associated with DNA fingerprinting.
DNA fingerprinting is the banding pattern created by electrophoresis. Processes associated with it is the Polymerase Chain Reaction (PCR). This is the duplication of DNA segments through repeated cycles. It uses a primer to start the duplication. A segment of DNA complementary to the targeted to the targeted sequence of DNA- and DNA polymerase is the enzyme used to duplicate these DNA strands
What are the steps of Polymerase Reaction Chain
1) DNA is denatured. Primers are attached to each strand. A new DNA strand is synthesise PC behind primers on each template strands.
2) Another round: DNA is denatured, primers are attached and he number of DNA strands is doubled.
3) continued rounds of implications swiftly produces large numbers of identical fragments.
