Biology

Question 1

Variation causes includes

Answer 1

Inhertiance - genes and DNA

Environment-food and weather

Question 2

What is variation

Answer 2

Variation is the presence of differences between living things of the same species!

Question 3

How many chromosomes are there?

Answer 3

46 (23 pairs) which contain tone of different genes

Question 4

What are genes made from

Answer 4

They are made of a small selection of DNA

Question 5

What is DNA

Answer 5

DNA: it is a long stand of genetic code that is divided into chromosomes.

Question 6

Wher is a chromozone found

Answer 6

It is found in a nucleus

There are 23 in a sex cell and 46 for every other cell

Question 7

Nucleus

Answer 7

Tells the rest of the cell what to do and contains chromosomes

Question 8

Sex pairs of chromosomes

Answer 8

Boy has 22 chromosomes xy girl has 22 chromosomes xx

Question 9

What does each gene code for

Answer 9

Each gene codes for a specific protein which gives our unique characteristics.

Question 10

Allele

Answer 10

An allele is a different form of gene.
E.g. if the gene is eye colour the allels could be:
Brown allele
Blue allele
Green allele

Question 11

Dominant alleles

Answer 11

always expressed if they are present.

Question 12

Recessive alleles

Answer 12

only expressed if there are 2 recessive alleles presented

Question 13

homozygous alleles

Answer 13

It is if an individual has 2 alleles that are the same

Question 14

Heterozygous

Answer 14

If an individual has 2 different alleles then it is called heterozygous alleles.

Question 15

How to lay out a punit square

Answer 15

Parents (red    yellow)
Phenotype (red         Yellow)
Genotype    (RR x rr)
Gametes sex cell   (R,R x r,r)
Square (100% red)

Question 16

Genotype

Answer 16

What the genes are

Question 17

Gametes

Answer 17

Gametes are the sex cells (different alleles).

Question 18

Phenotype

Answer 18

Phenotype is the alleles you can see.

Question 19

Selective breeding

Answer 19

This is when you selectively choose two organisms to reproduce a organism with beneficial traits.

Question 20

Genetic disorders

Answer 20

Genetically inherited disorders are conditions passed from parents to their offspring in their genes.

Question 21

Cysistic fibrosis disorder symptoms

Answer 21

It affects the breathing and digestive system.

The air passages in lungs are coated with a flow of mucus, which traps and removes bacteria.

In a person with cystic fibrosis, mucus is thicker than normal.

Question 22

What dissorder is cystic fibrosus disorder

Answer 22

It is a recessive disorder meaning it has to have two recessive genes to create affect and is quite rare

Question 23

Cystic fibrosis mid dna is a?

Answer 23

a disease which at the 1900s people would die as eight year old where now you could live to up to 30 years.

Question 24

Facts about cystic fibrosis mid dna disease

Answer 24

1 in 30 people carrie this recessive allele but aren’t affected

1 in 3600 people suffer from this disease

Question 25

Polydactyly

Answer 25

Polydactyly is a disorder that results in a child being born with extra digits to their hands or feet. These can be small stumps of soft tissue, or extra fingers or toes.

Question 26

Polydactyly cause

Answer 26

Polydactyly is caused by a dominant allele. Therefore, if one of your gens contains this allele, you will have the disorder. You cannot be a carrier of this disorder.

Question 27

Why is it impossible to be a carrier of polydactyly?

Answer 27

It is not possible to be a carrier of polydactyly as polydactyly is caused by a dominant allele. This means if you did have this disorder it would be shown and seeing that it is not you do not have it.

Question 28

Cloning

Answer 28

Clones are genetically identical individuals.

When bacteria reproduce, they divide in half. Each half contain identical genes

Question 29

Cloning of animals

Answer 29

The cloning of animals has many important commercial implications. It allows an individual animal with desirable features, such as a cow that produces a lot of milk, to be replicated several times. But the process takes much longer than it does with plants.

Question 30

The stages of cloning a mammal include:

Answer 30

the nucleus is removed from an unfertilised egg cell
the nucleus from an adult body cell, such as a skin cell, is inserted into the egg cell
an electric shock stimulates the egg cell to divide to form an embryo
these embryo cells contain the same genetic information as the adult skin cell
when the embryo has developed into a ball of cells, it is inserted into the womb of an adult female to continue its development

Question 31

Cloning plants tissue culture

Answer 31

take explants from the parent plant
transfer to plates containing sterile agar jelly
add plant hormones to stimulate the plant cells to divide
cells grow rapidly into small masses of plant tissue
add more plant hormones to stimulate the growth of roots and stems
transfer the plantlets into potting trays, where they develop into plants

Question 32

Asexual reproduction

Answer 32

This is when only one parent is needed

Question 33

Disadvantage of plant cloning

Answer 33

Reduces the variety of genes available (gene pool). Increase risk of disease or a change in the plants environment destroying a species

Question 34

Disadvantage of animal cloning

Answer 34

Cloning animals is unethical

Question 35

Cell cloning

Answer 35

Scientest clone human cells in the labatiory and use them to research into diseases.

Question 36

Disadvantages of selective breeding

Answer 36

Some examples of disadvantages include increased chances of genetic disorders. Animals with disorders include: pug, Rhodesian, british bull dog…

Reducing

Question 37

What is selective breeding

Answer 37

When producing offspring by choosing their best plants or animal to breed.

Question 38

Steps to breed organisms selectively.

Answer 38

Decide which characteristic of the species is most important

Select parents that show high level of the characteristic

Breed these individuals

Select best offspring and breed again

Repeat for many generations.

Question 39

What is a insulin

Answer 39

Regulates your blood sugars

Question 40

Selective breeding artificial insemination

Answer 40

When sperm is taken from tha male cow for human to selective breed and not into the female. It is then placed into the female’s uterus by the choice of humans.

Breeders use insemination to select certain characteristics and improve the speed of mating in larger amounts

Question 40

Selective breeding with plants

Answer 40

Selective breeding is also with plants; in the 17th century, Dutch growers cultivated orange carrots as a tribute to William of Orange. This was created be selective breeding.