genetics Flashcards
(22 cards)
what are chromosomes?
structures in cells made of proteins and DNA
where do you get your chromosomes from?
your mom and dad (parents)
What is the sex-chromosome combination for females?
XX
What is the sex-chromosome combination for males?
XY
What is an inherited trait?
A trait passed down from parents to offspring
What is an acquired trait?
A trait that one learns during their lifetime
What is heredity?
The passing down of inheritable traits from one trait to the next
What is a gene?
A part of a chromosome that contains the code for a specific trait?
What are alleles?
Different versions of genes that are represented by letters
What is a dominant allele?
A dominant allele is an allele that will always be shown in the phenotype when at least one is present in the genotype.
What is a recessive allele?
A recessive allele is an allele that represents a trait that is hidden when there is a dominant allele present in the genotype.
What does homozygous mean?
purebred - 2 of the same allele in the genotype
What does heterozygous mean?
hybrid - different alleles in the genotype
What is a phenotype?
The physical description of a trait that an organism has
What is a genotype?
The letter representation of the combination of alleles
What is a Mendelian trait?
A trait that has two alleles, a dominant allele and a recessive allele
What is incomplete dominance?
heterozygous genotype and the alleles mix to make a new variation of the trait that is a mix of the two alleles
What is co-dominance?
heterozygous and both alleles are dominant so they are both represented
What is a sex-linked trait?
A sex linked trait is a trait that is carried on the sex chromosomes.
Why do sex linked traits affect males more?
males only have 1 copy of the X chromosomes, so even if the trait is recessive, they only need 1 copy of it for it to be expressed.
How are sex-linked traits written?
A superscript next to the X
What is the difference between meiosis and mitosis?
meiosis is meant for reproduction (4 daughter cells) and mitosis is meant for copying or duplicating cells (2 daughter cells)
