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Flashcards in B1 Deck (29):
1

What are the two factors that cause variation?

genes

and

your environment

2

What is a make up of a cell?

Threre is a cell wall, containing cytoplasm and the nucleus of the cell. Inside the nucleus id chromosomes.

3

What is a chromosomes made up of?

It is made up of two lon gstrands that are coiled together to form a double helix. Between the strands are gene.s

4

What are the function of genes?

They send instructions to the cell so it can produce proteins structurally for the cell and also enzymes .

5

How many pair

6

 chromosmes are ther in each cell?

23

7

How many chromosmes came from the mother and the father?

23 from each

8

What is an allele?

A version of a gene

9

what the two types of alleles?

Dominant and recessive

10

What is the name of two different alleles.

hetrozygous

11

What is the meaning of a Genotype?

This refers to the combination of Alleles

12

What is the Phenotype?

This refers to the characteristics of the Alleles

13

What are the Alleles in human reproduction?

For the male it is X and Y where the Y Allele is smallerandmakes it different from X

Females just have two X Alleles

The Y Allele is dominant Allele

14

What is the cause of Huntington's disease?

It is a faulty dominant gene in the brain that causes gradual damge and it is fatal

15

What aer the symtoms of huntington's disease?

Involuntary movement

Clumsiness

Memory Loss

Mood changes

inability to concentrate

16

What causes cystic fibrosis?

Cystic fibrosis is a recessive disease that is caused by cell mebranes producing overly thick mucus that irritates and blocks the lungs and pancreas

17

What are the symptoms of Cystic Fibrosis?

Weight loss

difficulty breathing

chest infeactions

difficulty digesting food

18

What ethical questions does Huntington's disease raise?

Whether or not to inform your employer?

what to tell your life insures?

Whether to tell your family?

Whether to have children?

19

What are some types of gentic testing before and after birth?

Amniocentesis- where cells are collected from the aminiotic fluid surrounding the fetus

Chrionic villus sampling- taking cells from the placenta

heel prick for blood test

20

What is unethical about IVF? 

Embyros that possess genetic disorders may be discarded

21

What is Embryo screening or test in  IVF known as?

Pre-implantation genetic diagnosis(PGD)

22

What is another risk, even if your are diagnosed as not having the disorder?

It could be a false negative , meaning they actually have the disorder. It could also be a false positive meaning the opposite

23

What is the definition for a clone? 

An organism with identical DNA to another Organism

24

What is asexual reproduction?

This is where there is only one parent is needed.E.G. plants and bacteria

25

How do clones differ

When they are exposed to different environments

26

Advantages/disadvantages Of cloning and asexual reproduction

Characteristics are similsr in the offspring

plants can live isolation

there is no genetic variation

Diseases could easily wipeout society

27

How is cloning done?

The nucleus of the animal you are cloning is placed in a egg cell with no nucleus. Then it is implanted in the surrogate mother, Illegal to clone in UK

28

What  is the process of cell specialisation?

Differentiation

29

What are uses of stem cells?

They could be used to test drugs 

Understanding how differentiation works

Growing new oragans or rebuilding part of the sinal cord.