[otrivine]

(Original post by Sparkzz)
can u explain the answer to this please?

also, some more q's:

what is the difference between anaphase I and anaphase II?

hi sparkzz how are you is it ok if you can ask me questions from cloning part till the genome sequencing thats what i have revised that chapter is so long to revise and contain so much info!!

[Sparkzz]

(Original post by otrivine)
hi sparkzz how are you is it ok if you can ask me questions from cloning part till the genome sequencing thats what i have revised that chapter is so long to revise and contain so much info!!

im good thanks, stressing abt this exam!!! u?

yess sure, and u also ask me randoms qs from the specification!

a) what method of immobilising enzymes gives the highest rate of reaction?
b) name two advantages, and two disadvantages of cloning by tissue culture?
c) why is asepsis vital at large-scale culture?

[kimmey]

(Original post by Sparkzz)
can u explain the answer to this please?

also, some more q's:

what is the difference between anaphase I and anaphase II?

well for example, say i had a dihybrid genotype of AaBb ( where A and B are the dominant alleles). if i wanted to test cross it i would have to cross it with a homozygous recessive of aabb. this is because the genotype is always expressed in the phenotype of the organism and you will always get a 11:1 ratio in the phenotype. this can be seen if you draw a punnett square ( gametes as AB,Ab,aB,ab along the top and test cross as ab, ab along the left hand side)

[otrivine]

(Original post by Sparkzz)
im good thanks, stressing abt this exam!!! u?

yess sure, and u also ask me randoms qs from the specification!

a) what method of immobilising enzymes gives the highest rate of reaction?
b) name two advantages, and two disadvantages of cloning by tissue culture?
c) why is asepsis vital at large-scale culture?

a) adsorption,covalent bonding , membrane entrapment , also enzyme separated from substrate due to partially permeable membrane.
b) two advantages - quick to do , and can be resistant to diseases
two disadvantages- no genetic variation and therefore susceptible to diseases and pests due to non genetic uniformity.
c) because it would kill any microorganisms present in a biotechnological process as there could be microbes present such as in ferementers and they could contaminate the process as they can respire anaerobically to produce microbes which compete for space and food with the already microbes present in the fermenter.

[Sparkzz]

(Original post by otrivine)
a) adsorption,covalent bonding , membrane entrapment , also enzyme separated from substrate due to partially permeable membrane.
b) two advantages - quick to do , and can be resistant to diseases
two disadvantages- no genetic variation and therefore susceptible to diseases and pests due to non genetic uniformity.
c) because it would kill any microorganisms present in a biotechnological process as there could be microbes present such as in ferementers and they could contaminate the process as they can respire anaerobically to produce microbes which compete for space and food with the already microbes present in the fermenter.

They were right i think, but make sure u read the q! (a) asked which gives the highest reaction rates, which is adsorption

[Sparkzz]

(Original post by kimmey)
well for example, say i had a dihybrid genotype of AaBb ( where A and B are the dominant alleles). if i wanted to test cross it i would have to cross it with a homozygous recessive of aabb. this is because the genotype is always expressed in the phenotype of the organism and you will always get a 11:1 ratio in the phenotype. this can be seen if you draw a punnett square ( gametes as AB,Ab,aB,ab along the top and test cross as ab, ab along the left hand side)

ohhh would u have to say that it wud have to be homozygous reccesive as the heterozygous dominant alleles would always be expressed in the phenotype?

[otrivine]

(Original post by Sparkzz)
They were right i think, but make sure u read the q! (a) asked which gives the highest reaction rates, which is adsorption

ops yes sorry can i have 3 more again then i give u as well

[Sparkzz]

(Original post by otrivine)
ops yes sorry can i have 3 more again then i give u as well

(a) what is dutch elm disease caused by?
(b) what is non-coding dna?

[kimmey]

(Original post by Sparkzz)
ohhh would u have to say that it wud have to be homozygous reccesive as the heterozygous dominant alleles would always be expressed in the phenotype?

yep i think so, genetics is a bit weird for me sometimes

[otrivine]

(Original post by Sparkzz)
(a) what is dutch elm disease caused by?
(b) what is non-coding dna?

a) caused by fungal disease and the carrier is beetle which spreads the disease from one tree to the next by the mouth-parts as it sucks the SAP from the pholem .
b) It has many regulatory functions and is where it will not code for a protein and is called Junk DNA

[katiehockey22]

(Original post by MyselfEtAl)
Its a formula for calculating allele frequencies within a population (I think, ngl I still haven't looked over it fully ). If you have the green text book it comes after the part on natural selection/genetic drift - it'll probably be easier to just index it.

Thanks. We've just started it now

[Sparkzz]

Need to do well in thiss

[Lalaa]

Hey, can someone explain what ' mammary cells' are? please..

[otrivine]

(Original post by Lalaa)
Hey, can someone explain what ' mammary cells' are? please..

mammary cells are the cells which come from the sheep right to make dolly the sheep ?

[Lalaa]

(Original post by otrivine)
mammary cells are the cells which come from the sheep right to make dolly the sheep ?

yee thats right... but im wondering if theyr a special kind of cell.. or a reason for why that cell is used in Nuclear transfer? =\

[jwells]

(Original post by Lalaa)
yee thats right... but im wondering if theyr a special kind of cell.. or a reason for why that cell is used in Nuclear transfer? =\

I think mammary cells are like stem cells or contain stem cells in them and so they can differentiate into every kind of cell in a muticellular organism

[Lalaa]

(Original post by jwells)
I think mammary cells are like stem cells or contain stem cells in them and so they can differentiate into every kind of cell in a muticellular organism

yee dat sounds right.. Thankss!


also... is micropropagation and tissue culture the same method?

[jwells]

(Original post by Lalaa)
yee dat sounds right.. Thankss!


also... is micropropagation and tissue culture the same method?

Yes just with plants and then planting them

[Lalaa]

(Original post by jwells)
Yes just with plants and then planting them

Thankkss alott!

[The Illuminati]

(Original post by jwells)
I think mammary cells are like stem cells or contain stem cells in them and so they can differentiate into every kind of cell in a muticellular organism

(Original post by Lalaa)
yee thats right... but im wondering if theyr a special kind of cell.. or a reason for why that cell is used in Nuclear transfer? =\

Mammary cells are NOT stem cells in any way, they are normal somatic cells. They are used in example because when the example is given it is an example of sheep because the first successful mammalian clone was Dolly the Sheep and the mammary cell is the cell that was taken in that case. Any somatic cell can be used. These days skin cells are used because they are easy to access.