Lets go prt condenesed

Question 1

Steps in artificial embryo cloning for a cow (doesn’t matter which animal)?

Answer 1

An egg cell is extracted from a female cow and fertilised in a petri dish
The fertilised is left to divide at least once, forming an embryo in vitro (outside a living organism)
Individual cells from the embryo are separated and each is put into a separate petri dish, each cell divides and develops normally so an embryo forms in each petri dish
Embryos are implanted into female cows which act as surrogate mothers
Embryos develop in surrogate mothers and form offspring, all offspring genetically identical to each other

Question 2

Steps in Somatic Cell Nuclear Transfer (SCNT) for sheep(again animal doesn’t matter)?

Answer 2

A somatic cell (any cell that isn’t a reproductive cell) is taken from sheep A. The nucleus is extracted and kept
An oocyte (immature egg cell), is taken from Sheep B, it’s nucleus is removed to form an enucleated oocyte.
Nucleus from sheep A is inserted into the enucleated oocyte, the oocyte from sheep B now contains genetic information from sheep A.
The nucleus and the enucleated oocyte are fused together and stimulated to divide via electrofusion (electrical current is applied) producing an embryo
The embryo is implanted into a surrogate mother and eventually a lamb is born that is a clone of sheep A.

Question 3

What’s happens in transcription in relation to introns and exons?

Answer 3

Introns and exons are both copied into mRNA forming primary mRNA transcripts

Then in a process called splicing, the introns are removed and the exons join together, forming mature mRNA strands, this occurs in the nucleus

The mature mRNA then leaves the nucleus for the next stage of protein synthesis (translation)

Question 4

What are the steps of apoptis?

Answer 4

Enzymes in the cell break down important cell components such as proteins in the cytoplasm and DNA in the nucleus

As the cell’s contents are broken down, it shrinks and breaks into fragments

The cell fragments are engulfed by phagocytes and digested

Question 5

In depth explanation how the second step of Genetic engineering works?In depth explanation how the second step of Genetic engineering works?

Answer 5

The DNA fragment is inserted into a vector DNA (Vector is something used to transfer DNA into a cell, eg. plasmids (small circular molecules of DNA in bacteria, or bacteriophages (viruses that infect bacteria))

The vector DNA is cut open using the same restriction enzyme that was used to isolate the DNA fragment that containing the desired gene. So the sticky ends of the vector are complementary to the sticky ends of the DNA fragment containing the gene

The vector DNA and DNA fragment are mixed together with DNA ligase

DNA ligase joins up the sugar-phosphate backbone of the 2 bits, = ligation

Question 6

How can gene sequencing techniques be used to find whole genomes?

Answer 6

The BAC’S are then inserted into bacteria-each bacterium containing a BAC with a different DNA fragment

The bacteria divide, creating colonies of identical cells that all contain a specific DNA fragment, together the different colonies form genomic DNA libary

DNA is extracted from each each colony, and cut up using restriction enzymes producing overlapping pieces of DNA

Each piece of DNA is sequenced using chain-termination method, and put together back in order to give full sequence from BAC

Sequences from all BAC’s put together to form the whole genome

Question 7

Describe the 3rd step in the immune response of T lymphocytes activating B lymphocytes which divide into plasma cells?

Answer 7

B lymphocytes are another type of white blood cell, and are covered with proteins called anitbodies

Antibodies bind to complementary antigens to form an antigen-anitbody complex

Each B lymphocyte has a different shaped antibody on it’s surface

This together with other substances from T helper cells, activates the B lymphocyte, causing clonal selection

The activated B lymphocyte then divides by mitosis into plasma cells and memory cells = clonal expansion

Question 8

What occurs in the primary response that makes the secondary response much faster?

Answer 8

After being exposed to an antigen, both T and B lymphocytes produce memory cells, which will remain in the body for a long time. So the person is now immune

Question 9

Formula for Biodiversity?

Answer 9

D = 1 - (Sum of all the different species (Total number of individuals of that species/total number of organisms of all species)^2)

So will be adding up a value from each species

Question 10

What does the Rio convention on biological diversity aim to do?

Answer 10

Develop international strategies on the conservation of biodiversity, and how to use animal and plant resources in a sustainable way

Made it international law that conserving bio diversity is everyone’s responsibility

Provides guidance to governments on how to conserve biodiversity

Question 11

What are the aims of the CITES (convention on international trade in endangered species?

Answer 11

Regulates international trade on wild animals

Made it illegal to kill endangered animals

Helps to conserve species by limiting trade through licensing, and making it illegal to trade in products from endangered animals

Raises awareness of threats to biodiversity through education

Question 12

What does the countryside stewardship scheme aim to do?

Answer 12

Conserve wild life and biodiversity by improving habitats

Would pay landowners to follow their management techniques on how to manage land in the best way for habitats

Question 13

For a monogenic cross, what parents are you crossing, what will be the phenotype in the F1 ratio, and the phenotypic ratio in the F2?

Answer 13

Parents crossing will be homozygous dominant x homozygous recessive

Phenotypic ratio in the F1 will be all heterozygous offspring eg Rr

Phenotypic ratio in F2 will be 3:1 dominant to recessive

Question 14

For a dihybrid cross, what parents are you crossing, what will be the phenotype in the F1 ratio, and the phenotypic ratio in the F2?

Answer 14

Parents are homozygous dominant x homozygous recessive (eg RRYY x rryy)

Phenotypic ratio in offspring will all be heterozygous (eg RrYy)

Phenotypic ratio in F2 will be 9:3:3:1

Dominant both: dominant 1st recessive 2nd : dominant 2nd recessive 1st : both recessive

Question 15

For a codominant cross, what parents are you crossing, what will be the phenotype in the F1 ratio, and the phenotypic ratio in the F2?

Answer 15

Parents are homozygous for one allele and homozygous for the other allele, eg H(n)H(n) x H(s)H(s)

Phenotypic ratio in the F1 will be all heterozygous H(n)H(s)

Phenotypic ratio in the F2 will be 1:2:1
Homozygous for 1 allele : heterozygous : homozygous for the other allele

Question 16

What ratio will you get for a dihybrid cross involving a recessive epistatic allele - so if it’s recessive homozygous it will mask the affect of the other gene?

Answer 16

9:3:4

At least one dominant from each : The epistatic gene being dominant and the other gene being recessive : The effect of both episatic alles being recessive

Question 17

What ratio will you get if the there’s a dominant epistatic allele?

Answer 17

12:3:1

Question 18

Equation to predict allele frequency?

Answer 18

p + q = 1

p = the frequency of the dominant allele 
q = the frequency of the recessive allele

May have to combine with other equation in a question

Question 19

Equation to predict genotype frequency?

Answer 19

p^2 + 2pq + q^2 = 1

p^2 = the frequency of homozygous dominant genotype 
2pq = the frequency of the heterozygous genotype 
q^2 = the frequency of the homozygous recessive genotype

May have to combine with the other equation in a question

Question 20

What are the 8 taxonomic groups?

Answer 20

Domain 
Kingdom 
Phylum 
Class 
Order 
Family 
Genus 
Species

Donkey Kong Pulls Cock Out For Gorilla Sex

Question 21

What’s the formula for standard deviation?

Answer 21

s^2 = All values added up of ((New x value - the mean)^2)/(n-1)

s = the square root of that

Question 22

How can you purify DNA?

Answer 22

Via a precipitation reaction

Break up cells of sample using a blender

Make a solution of detergent, salt and distilled water

Add the broken up cells to a beaker containing the solution and heat in a water bath

The detergent in the mixture breaks down the cell membranes, and the salt binds to the DNA causing it to clump together, and warm temperature prevents the stops the enzymes in the cells working properly so DNA not broken down

Put beaker in a ice bath, and then filter

Transfer to a testube and protease enzymes to the filterered mixtures, which will break down any proteins

Dribble cold ethanol down side of tube so it forms a layer on top, causing DNA to form a white precipitate