Explain the effect of adding an inhibitor of DNA polymerase in a cell
Nucleotides would match up to their completmentry nucleotiudes on original DNA, but they would not join to form a new strand
1 of 13
In an experiment whay were the bacteria wihch had incorperated the heavy isotope of notrogen washed before transfer to a medium containing normal nitrogen
to prevent contamination, so 15N would not be incorperated into the new strand
2 of 13
Explain how the change in one base along the DN may result in a protien becoming non functional
differnt base may code for a different aminio acid, so sequence of amino acids in polypeptide produced would be different
3 of 13
WHat is the main difference between prophase of mitosis and prophase 1 of meiosos
homologus chromasosmesdo not pair up during prophase of mitosis but pair up to form bivalents in prophase 1 of meisos
4 of 13
why can mules not produce gametes and are therefore sterile
Gametes produced by meiosis, hmologus chromasoses need to pair, not possible with 63 chromasosmes, thterefore no meiosos, therefor no gametes produced
5 of 13
name 2 structures which produce secretions that aid sperm mobility
seminal vesicles, prostate gland
6 of 13
what do intersital cells do
secrete testosterone
7 of 13
why is internal fertlisation a necassary adaptaton to life on land
independant of water as sperm are introduced directly into the female tract
8 of 13
what is the function of the enzymes released after the acrosome membrane ruptures
to soften the layer of cells surrounding the oocyte to enable sperm to penetrate the egg
9 of 13
why do wind polinated flowers produce large quantities of pollen
much pollen fals to reach the stigma of another flower therefore is wasted
10 of 13
state 2 ways in which pollen grains are adapted for seed dispersal
secretion of enzymes to digest a apth and also may provide nutrients for growth
12 of 13
how is the triploid endosperm nucleaus formed
1 of the male nuclei form the polen tube fuses with both polar nuclei in the embryo sac
13 of 13
Other cards in this set
Card 2
Front
In an experiment whay were the bacteria wihch had incorperated the heavy isotope of notrogen washed before transfer to a medium containing normal nitrogen
Back
to prevent contamination, so 15N would not be incorperated into the new strand
Card 3
Front
Explain how the change in one base along the DN may result in a protien becoming non functional
Back
Card 4
Front
WHat is the main difference between prophase of mitosis and prophase 1 of meiosos
Back
Card 5
Front
why can mules not produce gametes and are therefore sterile
Comments
No comments have yet been made