GCSE WJEC Biology- genetics

bb

homozygous (recessive) ((same))

Bb

hetrozygous (different)

treating genetic disease

no cure- have to treat symptoms

no. of divisions MITOSIS

1

stem cell use in medicine

could use SC to create specialised cells to replace ones damaged by disease/ injury

dna fragments are separated into …. which is …… to a person and called your ….. …..

dna fargments are separated into bands which is unique to a person and called your genetic profile

ethics of genetic profiling

parents could decide to abort baby if they have a faulty gene + should insurance companies and employers have access to this information

mitosis uses

• grow in size

• replace dead cells

  • repair damaged tissues

MEIOSIS daughter cells are

genetically different

result of cells dividing uncontrollably

creates tumour- causes cancer

no. of chromosomes in daughter cells MITOSIS

full set (46 in humans)

DNA shape

double helix

C

cytosine

G

guanine

T

thymine

A

adenine

continuous variation + example

controlled by more than one gene- no distinct categories e.g height

discontinuous variation + example

one gene- can only be in one distinct category e.g blood type

undifferentiated cells name + ability

stem cells- potential to divide + produce any kind of cell

what is gene therapy

type of genetic modifiation- healthy genes inserted into cells with faulty genes

ways DNA profile can be used

criminals

relatives

genetic disease

phenotype

word to describe your appearance

differentiation definition

process by which a cell becomes specialized for its job

no. daughter cells MEIOSIS

4

MITOSIS daughter cells are

genetically identical

no. of divisions MEIOSIS

2

no. daughter cells MITOSIS

2

no. of chromosomes in daughter cells MEIOSIS

half set (23 in humans)

MITOSIS defenition

when a cell reproduces itself by dividing to form 2 identical offspring

C paired with

G

A paired with

T

ethics of stem cell research

some ppl see it as killing an embryo= bad (killing a person)

others see it than no more than a cluster of cells- taking stem cells can cure diease

for + against genetic modification of crop plants

FOR

increased yields

tobacco plants light up when need watering

AGAINST

unethical

concerns on effect on wildlife

eating them could harm human health

Label the diagram

…

gene

a section of DNA thats code for a particular characteristic

allele

different type of a gene

how DNA determines protein structure

3 bases make one triplet code- 1 triplet code determines a sequence of amino acids which form proteins

why you might not have confidence in the mean

small sample

method used to deliver dominant alleles to lungs

inhaler