B1.6 Variation, Reproduction And New Technology Flashcards Preview

GCSE AQA Biology (old spec) > B1.6 Variation, Reproduction And New Technology > Flashcards

Flashcards in B1.6 Variation, Reproduction And New Technology Deck (29):

Define asexual bonding

Your cells reproduce by dividing into two identical cells individually


Define sexual reproduction

Involves a male sex cell and a female sex cell (gametes) from two parents and they join together and fertilise


Define gamete

Sex cell which has half the chromosome number of an ordinary cell


Define variation

There is a varied number of ways species can turn out. This is why we're not the same.


What's an advantage of sexual reproduction and a disadvantage?

Ad - introduces variety
Disad - relies on two different sexes, risky


What's an advantage of asexual reproduction and a disadvantage?

Ad - replaces worn out tissue and helps cell grow
Disad - doesn't make variety, very limited


Why are humans all different including identical twins?

Environmental differences
One person might eat a lot more than the other person therefore their weight is different


What are the two ways of cloning plants?

Taking cuttings of the plant and it will regrow
Using part of the tissue from the plant and cloning thousands of the same tissue from it


What are the steps for embryo cloning?

1. Divide each embryo into several individual cells
2. Each cell grows into an identical embryo in the lab
3. Transfer embryos into their host mother which have been given hormones to get them ready for pregnancy
4. Identical clones are born. They're not biologically related to their mothers


What example is there of mammal cell cloning?

Dolly the Sheep was an exact genetic copy on another adult sheep


What are causes of variation?

Genetics from parents


Gametes contain ________ which pass on ________ from parents to children.



Are these things genetic, environment or both?
A) having a scar
B) having naturally curly hair
C) being very tall

A) environment
B) genetic
C) both


How many parents are involved in sexual reproduction and asexual reproduction ?

Sexual - 2
Asexual - 1


What organisms produce by asexual reproduction and sexual reproduction?

Asexual - plants, bacteria, starfish
Sexual - mammals (humans, pandas, tigers etc.)


Does sexual reproduction involve gametes? Does asexual reproduction involve gametes?



What are the similarities between asexual and sexual reproduction?

Both copy chromosomes to start with
Both produce offspring
Both involve DNA and genes


What are differences between asexual and sexual reproduction?

Asexual splits the cells once, sexual splits cells twice
Asexual makes identical genes, sexual makes varied genes
Asexual doesn't involve gametes, sexual does involve gametes
Asexual involves one parent, sexual involves two parents
Asexual is quicker, sexual is slower


Explain how sexual reproduction produces variation.

Sexual reproduction involves two gametes meaning DNA is taken from two parents. This means the chromosomes that join together are from random gametes. This means there are multiple possibilities of the genes that could join together - creating variation.


Define clone

An organism that is genetically identical to its parent


What are the issues with embryo transplants economically and ethically?

Economic - expensive, posted all around the world which costs a lot
Ethical - altering embryos can be unethical, might destroy embryos which could be seen as killing life


What are the steps for adult cell cloning?

1. The nucleus is removed from an unfertilised egg cell
2. At the same time the nucleus is taken from an adult body cell eg. a skin cell
3. The nucleus from the adult cell is inserted in the empty egg cell
4. The new cell is given a tiny electric shock that makes it start dividing to form embryo cells. These contain the same genetic information as the original adult cell and the original adult animal.
5. When the embryo has developed into a ball of cells its inserted into the womb of an adult female to continue its development.


What are advantages of adult cell cloning?

We can make copies with the characteristics we want
We can make many copies of the kind of animal we want quickly
Extinct and endangered species can be repopulated
Makes it possible to produce a genetically identical copy of an individual tissue or organ to for transplants and they won't be rejected


What are disadvantages of adult cell cloning?

Cloning is regarded as immoral by many people
We reduce variety in a species
Cloned animals have short life spans
Thousands of eggs are used - wasteful and expensive


What are some ethical issues with genetic engineering?

Health risks
Not much variation
There could be long term effects we don't know about yet
Could inflict pain on animals
Picking specific characteristics isn't natural
In the future clones could be very intelligent and have feelings but we might not treat them well
What legal rights are there
Who's eligible for clones?


How do you make insulin?

1. Human cell with insulin gene in its DNA and bacterium with ring of DNA called a plasmid
2. Insulin gene cut out of DNA by an enzyme and plasmid taken out of bacterium and split open by an enzyme
3. Insulin gene inserted into plasmid by another enzyme
4. Plasmid with insulin gene in it taken up by bacterium
5. Bacterium multiplies many times
6. The insulin gene is switched on and the insulin is harvested


How would farmers genetically modify their crops?

Pest resistance
Frost resistance
Diseases resistance


What are benefits of genetic engineering?

We can genetically make proteins we need in the exact amounts we want.
We can improve growth in organisms
Improve quality in crops
We could potentially modify unhealthy genes


What are the disadvantages of genetic engineering?

Could be long term side effects
Might be unhealthy
Ethical issues