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Which type of cell division produces cells with the diploid (2n) number of chromosomes?
Meiosis
Mitosis
Which type of cell division produces cells with the haploid (n) number of chromosomes?
Which type of cell division produces somatic (body) cells?
Which type of cell division produces gametes?
Which type of cell division is used in asexual reproduction and leads to no genetic variation?
Which type of cell division is used in sexual reproduction and leads to genetic variation?
True or false? In order to undergo cell division, the chromosomes in the cell need to be copied.
Where would you find totipotent, undifferentiated stem cells?
In zygotes and embryos
In the microvilli in the small intestine
In bone marrow
In the tips of shoots and roots
In the parietal lobe of the brain
Why do gametes (sperm and ova) have a haploid (n) number of chromosomes?
They are too small to carry the diploid (2n) number of chromosomes
When they fuse in fertilisation, the resulting zygote has the correct diploid (2n) number of chromosomes
Half of the chromosomes are missed out as the gamete is a short-lived cell
True or false? Research on embryo stem cells is not considered unethical as the embryo is not yet alive.
True or false? In 2010, the first organ grown using stem cells was successfully transplanted into a human child.
Which scientist came up with the idea of genes but was ignored for many years as DNA had yet to be discovered?
Crick and Watson
Mendel
Darwin
Lamarck
What does a codon (a sequence of three nucleotide bases) code for?
Nothing
A molecule of glucose
An amino acid
What is the best definition of a recessive allele?
An allele that is "masked" by the effect of a dominant allele
An allele that is rarely passed down
An allele that causes learning difficulties
What would be the genotype of a person who was homozygous dominant for brown eyes?
BB
Bb
bb
True or false? A person's phenotype is the combination of alleles that they have.
What is a Punnet square?
A square number that is 1 less than a prime number, discovered by J W Punnet
A biological phenomenon exhibited by ravens which causes them to fly in a square formation
A grid which shows all possible combinations of alleles and the corresponding phenotype expressed
Which of these diseases are caused by dominant alleles?
Sickle cell anaemia
Huntington's disease
Cystic fibrosis
Polydactyly
True or false? Cystic fibrosis causes mucus to become thick and sticky, often leading to problems with breathing, digestion and fertility.
True or false? A carrier of cystic fibrosis will have the heterozygous genotype Cc.