Genetics & Reproduction Flashcards
What is asexual reproduction?
Offspring produced by cell division, not fertilisation. Offspring is identical to parent
What is sexual reproduction?
The production of new individuals by the combination of genetic information from individuals of different sexes
What is fertilisation?
The joining of male and female gametes to form a zygote
What is an allele?
The alternative forms of a gene that code for variations of a specific trait
What are 3 key points about meiosis? (name a few extra)
- Cell division for producing sex cells
- Division of parent cell twice (meiosis I & II)
- Each daughter cell has a haploid number of chromosomes
What are the 4 phases of meiosis that occur twice?
- Prophase
- Metaphase
- Anaphase
- Telophase/Cytokinesis
What occurs during prophase in meiosis?
- Duplicated homologous chromosomes pair up and exchange segments
- There is an exchange of genetic material between the maternal and paternal chromosomes
What occurs during metaphase in meiosis?
- Chromosomes line up
- Independent assortment occurs due to random orientation of maternal and paternal chromosomes when they line up ans split
What occurs during anaphhase in meiosis?
Homologous pairs separate
What occurs during telophase/cytokinesis in meiosis?
- Daughter cells separate nuclear membrane followed by cell membrane resulting in 2 daughter cells
What is a phenotype?
The physical expression of a genotype (genetic code) into an observable trait.
What is variation?
Diversity of genetic and phenotypic traits within and between populations
Draw a diagram to show the sources of variation
- Sexual reproduction processes
- Mutations
/ - Change in genotype
/ - Environmental factors
/
Change in phenotype
What are 3 ways variation can occur in sexual reproduction?
- Crossing over
- Assortment of chromosomes during metaphase
- Random fusion of gametes
