biology corrections paper 1

meiosis forms gametes

DNA extraction core prac

protease added to break down proteins, nuclear membrane

HIV destroys white blood cells, weakening the immune system, making the person more suspectible to other pathogens

clinical trials

use placeboes and double blind trials

interphase is not part of mitosis

genetic engineering

gene for characteristic first identified

antiseptic core prac: aseptic techniques

work next to bunsen + only lift lid slightly

lytic pathway

inject viral DNA into host, uses host cell resources to make new viral parts, virus components assembled inside cell, cell lyses releasing viral particles into bloodstream

antibiotics

inhibit cell processes, so bacteria cannot grow, do not affect host cell

concave lenses for short

sightedness, convex for long

stem cell treatment

divide by mitosis so are unspecialised, can differentiate into any type of cell so no embryo needed, will not be rejected + can replace tissue

selecive breeding happens over generations

distribution analysis

soil testing

potato cells will not burst due to cell wall with cellulose for support

non

coding region mutation

monoclonal antibodies in preganacy tests

detects hCG hormone in urine, antigen binds to antibody in test, coloured bead attached causes line to appear because antibodies are immobile

bacteria: exponential growth

outbreaks occuring despite immunisation: not fully effective, can decrease with age

chemical defenses: HCl in stomach, lysozyme in tears

high body mass > insulin resistance

glucose released from pancreas

darwins theory of evolution

acquired characteristics are not inherited

evolution

gradual change in characteristics of a species over time

scientists unsure of ancestory of hominids

too many gaps in fossil records, not sufficient genetic evidence

pros of selective breeding

ability to select for certain characteristics, increases characteristic within population

cons

takes long time, does not guarantee selected outcome due to variation, alleles have to already exist in population, may cause extinction of certain alleles

pros of genetic modification

faster, allows for precise manipulation of genes, allows genes from different species to be introduced to another

cons of genetic modification

could result in genes spreading to wild populations

bypass surgery

effective in emergencies, is invasive so may lead to complications/infections

lifestyle changes

may be disruptive for patient, takes longer

monoclonal antibodies as cancer treatment

inject antigen into a mouse, lymphocytes produced that make antibodies specific to antigen, lymphocytes fuse with cancer cells to form hybridoma cells, which produces monoclonal antibodies specific to cancer cells and can divide over and over again, cancer drugs can be attached to monoclonal antibodies, so drugs only delivered to target cells, reduces volume of drug needed

exercise lowers risk of heart disease

lowers blood pressure by removing fat form blood vessels/arteries

herd immunity

fewer people develop the disease and pass it on

lift lid of petri dish a little

to prevent microorganisms from the air entering the dish

smokers breathe in CO

benefits of discovering base sequences

track evolution, diseases can be better understood, new medicines/cures for diseases, new GMOs can be made

DNA extraction core prac

break down cell membranes because DNA is in the nucleus

genetic disease

a disease that can be inherited

phenotype

[gender] with/out [condition]

carriers

parents both carry alleles

darwins theory of evolution

acquired characteristics are not inherited

evolution

gradual change in characteristics of a species over time

scientists unsure of ancestory of hominids

too many gaps in fossil records, not sufficient genetic evidence

pros of selective breeding

ability to select for certain characteristics, increases characteristic within population

cons

takes long time, does not guarantee selected outcome due to variation, alleles have to already exist in population, may cause extinction of certain alleles

pros of genetic modification

faster, allows for precise manipulation of genes, allows genes from different species to be introduced to another

cons of genetic modification

could result in genes spreading to wild populations