genotypes and phenotypes Flashcards
(15 cards)
what do genes code for
they code for proteins and this includes enzymes, transport, storage etc.
what do the DNA sequence of a gene determines
it determines the amino acid sequence for the protein it encodes
what do polygenic genes mean
multiple genes that playing together that give rise to smth
what determines human traits and Diases
polygenic genes and environmental factors
explain chromosome
they are tightly packed chromatin which are DNA protein complexes
explain DNA
only 1-2% of our DNA encodes for proteins. they are made up of genes- the gene sequence determines the Amin acid sequence for the protein it encodes.
what do autosomes mean
chromosomes from 1-22
what are homologues chromosomes
they are the same. one is inherited from mum and the other is from dad
difference between wert and dry earwax
its linked to a protein transporter that helps lipids move across membranes.
what do alleles mean
they are variations in genetics
whats the difference between between gene and allele
the phenotype is determined by the alleles. they can be the same type or different. the alleles are in the genes.
what does the locus mean
the location where the same genes in homologous chromosome are found
why are alleles sometime different
this is because to slight differences in the DNA sequence. we can have different alleles for one gene.
compare genotypes vs phenotype
genotype: combination of alleles for a particular gene
phenotype: measurable characteristic arising from the genotype and its interaction with environmental factors
what is a sickle cell trait
its a mutation in chromosome 11 resulting in abnormal haemoglobin beta subunit. A is dominant and codes for normal haemoglobin while S is the allele for sickle. it’s recessive. sickle cell disease is a autosomal recessive disorder. heterozygotes exhibit sickle cell trait - an incomplete phenotype. haemoglobin deforms and leads to red blood cells becoming brittle. they stick together and jam blood vessels- no oxygen, painful. someone with heterozygote will only have sickle red blood cells under stress (incomplete phenotype)
