B2.7.1 Cell division and inheritance Flashcards
Define these key terms:
- Heterozygous
- Homozygous
- Heterozygous= A pair of genes where one is dominant and the other recessive
- Homozygous= A pair of genes where both are dominant or both are recessive
Define these key terms:
- Recessive allele
- Dominant allele
The characteristic that will show up in the offspring:
- Recessive= only if both of the alleles are inherited - Dominant= as long as one of the alleles is inherited
Define these key terms:
- Genotype
- Phenotype
- Genotype= describes the genetic make-up of an organism
- Phenotype= describes the physical characteristics that an organism has
By what method do body cells divide by?
Mitosis
What happens in mitosis?
- Copies of the genetic info is made
- Cell divides once= 2 identical body cells
Order these words:
Chromosome, Organism, DNA, Cell/Nucleus
- Organism
- Cell/Nucleus
- Chromosome
- DNA
What happens to the cells in the reproductive organs (the testes and ovaries)?
They divide to form gametes
What happens when a cell divides to form gametes?
- Copies of the genetic info is made
- Cell divides twice to form four gametes (each with a single set of chromosomes)
“Plant cells lose the ability to differentiate at an early stage in life” True or False
False, they retain the ability to differentiate throughout life
Where can stem cells be found and what can they do? (in general)
- Found in human embryos and adult bone marrow
- Can develop/differentiate into any kind of human cell
What can stem cells treat? (2 things)
- Paralysis
- Blood diseases (sickle cell anaemia, makes blood cells)
Does asexual reproduction use mitosis or meiosis? Give a reason for your answer
Mitosis because the new cells are genetically identical
What is produced in meiosis?
Gametes= Cells which have half the normal number of chromosomes
Mitosis is when a cell…
…reproduces by splitting to form 2 identical cells
