exam 2 Flashcards
evolution
- have elvoled by natural selection;
- variation / varied / vary in shape / colour;
- originally there would have been mutation / mutated;
- not seen by predators / not eaten / camouflaged / not attacked / eq;
- survive / survival / survival (of the fittest); 6. reproduce / produce offspring / eq;
- pass on allele / gene / DNA;
diffusion
Diffusion is the net movement of particles from an area of higher concentration to an area of lower concentration
The bigger the difference in conc the faster the rate of diffusion
Liquid and gas particles are free move about randomly
selective breading
Process:
From existing stock select the stock with best charcteristcs
Bread them with each other
Select the best of the offspring bread them together
Continue the process over serval generations and the traits get stronger and stronger for farming better yield will be produced.
restriction enzymes
enzymes recognise specific sequences of DNA and cut out the DNA
Ligase enzymes
joining up two pieces of DNA
Dominant allele
always determines the characteristics in a phenotype
answer to 1 a
testis
answer to 1 b
anther
answer to 2a
1
The acrosome contains digestive enzymes
to break down outer layer of the ovum
describe the route taken by the sperm cell from when iyt enters the woman’s body to the site of fertilisation of thug
it goed psst the cervix after entering the vagina up the uterus lining through the fallopian tube where is meets the egg
why the father determines the sex of baby
females only have xx which is what makes it female where as the males have the xy chromosomes contains the Y chromosomes which can determine weather the baby is a boy
answer to 2f
man a has a higher amount of sperm cells
man a sperm cells has no deformity
answer 2 g
45 %
difference between dominant allele and a recessive allele
dominant allele always determines the chartists in a phenotype while recessive allele
A recessive allele is only expressed if the individual has two copies and does not have the dominant allele of that gene
explain albinos recessive or dominant
it is a recessive allele as it is largely not shown and even though there is one affected it docent show in all the children +
suggest an advantage of using afrtical insemination to fertile
it is safer for the cow
what is meant by transgenic
Transgenic means that they contain genes transferred from other species
give role of restrictive and ligase
Restriction enzymes recognise specific sequences of DNA and cut the DNA at this point
Ligase enzymes joining up two pieces of DNA
explain the factors that affect the rate of movement in and out substance into and out
surface area to volume ratio - rate of all increased when there is a larger surface area
distance: the shorter the distance the faster the diffusion
temperature: move faster when they get warmer increaser them
conc gardent: in and out of cells faster when there a big con only increases rate of dif and osmos and not active transport
size of particles: smaller particles will diffuse faster
describe the differences between diffusion and active transport
the diff between diff and active transport diffusion moves with the conc gardent whereas At goes against it. furthermore at requires energy while diff dent and is a passive process
what leads to variation
male gamete and female gamete then combine at random during fertilisation so the offspring inherits a random mixture of chromosomes from both parents
also mutation which is a random change that happens in a chromosome and mutations can be inheritented and cause alterations in the base pair
rat question
since the rats are homozygous they have alleles are the same it is easy to spot any changes
sperm mitrocidria question
realises energy needed for sperm to swim and fertilise egg
