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In this chapter of IBDP Biology, we will learn about terminologies and inheritence.
Terminologies
- When it comes to IBDP Biology, Genes - It’s a sequence of bases on a DNA molecule coding for a sequence of amino acids in a polypeptide chain
- Allele - an alternative form of a gene, occupying a specific locus on a chromosome
- Genotype - genetic makeup of an organism
- Phenotype - physical and chemical characteristics that make up the appearance of an organism
- When it comes to IBDP Biology, Recessive - Allele-allele that are not reflected in the phenotype when in a heterozygous state but only in a homozygous state
- Dominant Allele - Allele that are reflected in the phenotype even in a heterozygous state
- Homozygote - A diploid organism that has inherited the same alleles for any particular gen from both parents
- Heterozygote - A diploid organism that has inherited different alleles from each parent.
Monohybrid Inheritance
- When it comes to IBDP Biology, it involves monohybrid crosses where one gene is considered at a time in a genetic cross.
- Monohybrid cross involving homozygotes leads to production of offspring with the same phenotype
- Monohybrid cross involving heterozygotes leads to production of offspring with the following genotypes: Homozygous dominant, Heterozygousm Homozygous recessive
Test Cross
- It’s a type of cross that is done in order to reveal the type of parental genotype.
- If an organism shows a recessive characteristic in its phenotype, it must have a homozygous genotype.
- If an organism shows dominant characteristics, then it may be either homozygous dominant or heterozygous.
- Dominant characteristics can only be distinguished from the offspring they produce in a particular cross.
This is the end of this topic
