Genetics Flashcards
What are the two methods of cell division
Mitosis & meiosis
What cells does Mitosis occur
All cells apart from gametes (sex cells)
Why does mitosis occur ( 2 )
1/ growth
2/ replace cells
what is the first step of mitosis
The genetic material copies itself
What is the second step
The genetic material separates and starts to form another nucleus
what is the third step
The nuclei fully separate to form two nuclei
The daughter cells have the ….. chromosomes
same ( 46 per cell )
where does meiosis happen in females
ovaries
where does meiosis happen in males
testes
How many new cells does one meiosis process produce
4
how many chromosomes does a double set have
46
How many sets and chromosomes do cells produced in meiosis have
1 set (23 cells per cell)
what is the first step of meiosis
genetic material copies itself
what is the second step
cells divide into 2 cells with double sets each
what is the third step
cells divide into 4 cells, each with a single set
what is it called when and egg cells meet
zygote
What are stem cells from embryos called
embryonic stem cells
What 4 things could be cured with stem cell research
1/ Parkinson’s disease
2/ spinal cord injuries
3/ new organs
4/ type 1 diabetes
What are the social standpoints on stem cell research ( 3 )
1/ save lives
2/ cure diseases
3/ save costs
What are the ethical standpoints on stem cells
1/ killing humans?
2/ no right to interfere (religious views)
Every human cell has how many chromosomes
46
Chromosomes are made from
DNA
DNA is in which shape
Double helix
the sections of DNA are called
Genes
Genes control:
Features
If you have an x and y chromosome you are a
male
if you have an x and an x chromosomes you are a
female
Fathers pass on which sex chromosomes
x and y
Mothers pass on which sex chromosomes
x and x
What is the possibility a baby is a male
50%
what is the definition of a gene
short section of DNA that codes for a protein
what are the 4 bases in DNA
A C G T
How are genes programmed
ordering the bases
What type of bases are on the other side
The complimentary bases
How many bases code for 1 type of amino acid
3
what are proteins made from
amino acids
What could DNA fingerprinting be used for ( 2 )
1/ Paternity & Maternity
2/ Criminal identification
What is an allele
One version of a gene
What is polydactlyly
Extra toes and/or fingers
Polydactlyly is what kind of genetic disorder
dominant
Cystic fibrosis affects what part of the cells
membranes
What does it affecting membranes cause
thick, sticky, mucus
What are the macroscopic effects of cystic fibrosis
1/ Affects pancreas and therefore digestion
2/ Affects lungs and lining of the airways and therefore can stop oxygen getting oxygen getting in the blood
Cystic fibrosis is what kind of genetic disorder
recessive
What is meant by ‘genotype’
The combination of alleles for a characteristic
What is meant by ‘phenotype’
The feature or characteristic that is expressed
What is meant by heterozygous
Two different alleles
What is mean by homozygous
Two same alleles
Why did Gregor Mendel use pea plants
They grew easily and fast
What was Gregor’s first experiment
Mixed 2 purebred plants: one tall and one short
What was the result of Gregor’s first experiment
All the plants were tall
Why was the first result unusual
Scientists at the time thought the plants produced would be somewhere in the middle
What was his second experiment
Mixing two of the f1 generation plants
What was the result of the second experiment
Mostly tall but a few short plants, none in the short (ratio of 3:1)
What conclusion was drawn from the experiments ( 2 )
1/ The plants passed on inheritance factors
2/ One plant passed on one feature and the other plant, another
Why wasn’t Mendel’s work recognised at the time ( 3 )
1/ He wasn’t a scientist, he was a monk
2/ His work was not published widely
3/ Genes had not been discovered
What are the social issues of embryo screening ( 3 )
1/ Save lives
2/ Eradicate disease
3/ Increase quality of life
What are the ethical issues of embryo screening ( 3 )
1/ Killing humans?
2/ No right to interfere
3/ designer babies
What are the economical issues ( 3 )
1/ Save costs
2/ Medical treatment
3/ Drugs
