Inherited change (complete) Flashcards
What is inheritance?
The process by which genetic information is passed from parents to offspring.
What is a gene?
A segment of DNA that contains the instructions for building a specific protein.
What are alleles?
Different versions of a gene that can exist at a specific locus on a chromosome.
What is the genotype?
The genetic constitution of an individual, represented by the alleles they possess.
What is the phenotype?
The observable physical or biochemical characteristics of an organism, determined by its genotype and/or environmental factors.
What is a homozygous genotype?
A genotype consisting of two identical alleles for a particular gene. (both dominant/both recessive)
What is a heterozygous genotype?
A genotype consisting of two different alleles for a particular gene. (dominant and recessive)
What is a dominant allele?
An allele that expresses its phenotype even when only one copy is present in a heterozygous individual.
What is a recessive allele?
An allele that only expresses its phenotype when two copies are present in a homozygous individual.
Is not expressed in phenotype if only one copy present (heterozygous)
True or False: All mutations are harmful, why?
False - some can provide protection against certain environmental changes/factors like diseases or climate changes.
What is a gene mutation vs a chromosomal mutation?
A change in the nucleotide sequence of DNA that occurs randomly.
A mutation that affects the structure or number of chromosomes.
What does the term ‘monohybrid cross’ refer to?
A genetic cross that involves one trait with two alleles.
What is a dihybrid cross?
A genetic cross that involves two traits, each with two alleles.
What is the law of segregation?
The principle that during gamete formation, the alleles for a trait separate so that each gamete carries only one allele for each gene.
What is the law of independent assortment?
The principle that alleles for different traits are distributed to gametes independently of one another.
When does Codominance occur?
Codominance occurs when both alleles are fully expressed in the phenotype.
What is incomplete dominance?
A form of inheritance in which the phenotype of a heterozygote is intermediate between those of the two homozygotes.
The dominant allele doesn’t fully mask the expression of the recessive allele, so both are expressed.
What is polygenic inheritance?
Inheritance of a trait that is controlled by multiple genes, resulting in a range of phenotypes.
What are sex-linked traits?
Traits that are associated with genes located on sex chromosomes. (usually the X chromosome)
What is the purpose of a pedigree analysis?
A method used to understand the inheritance of genetic traits from parents to offspring, and assess the likelihood of genetic disorders in offspring.
What is genetic drift?
A mechanism of evolution that involves random changes in allele frequencies in a population, due to a random selection of certain genes.
Occurs when the allele itself is not responsible for the change in its frequency.
What is natural selection?
The process by which individuals with favorable traits are more likely to survive and reproduce, passing on their favourable alleles to their offspring.
What is gene flow?
The transfer of genetic variation from one population to another through migration/The exchange of alleles between two or more populations.
What is genetic engineering?
The direct manipulation of an organism’s genes using biotechnology.
