Inheritance 5.0 / 5 based on 1 rating ? BiologyInheritance and SelectionA2/A-levelAQA Created by: J.E.C.Created on: 15-01-14 10:13 When populations are geographically isolated, there is ___, so their ___ are also isolated? interbreeding, genes 1 of 20 Define genotype? The genetic composition of an organism. 2 of 20 The genotype describes all the ___ that an organism contains? alleles 3 of 20 What is a mutation? A change in the sequence of bases in DNA. 4 of 20 A mutation may be inherited, if...? It occurs in the formation of the gametes. 5 of 20 Define phenotype? The characteristics of an organism, often visible, resulting from both its phenotype and the effects of the environment . 6 of 20 What is a modification? Any change to the phenotype that does not affect the genotype, so is not inherited. 7 of 20 What is a gene? Length of DNA on a chromosome, normally coding for a particular polypeptide. 8 of 20 The polypeptides that are coded for on the DNA, make up the ___ that are needed in the ___pathway that produces that characteristic? enzymes, biochemical 9 of 20 What is an allele? One form of a gene. 10 of 20 The position of a gene on a chromosome is known as the ___? locus 11 of 20 Only one ___ of a gene can occur at the locus of any one chromosome? allele 12 of 20 What are homologous chromosomes? A pair of chromosomes that have the same gene loci and therefore dtermine the same features. Capable of pairing during meiosis. 13 of 20 If the allele on each of the chromosomes is the same, the organism is ___? homozygous for the character 14 of 20 If the two alleles are different, it is therefore ...? heterozygous 15 of 20 The allele for the heterozygote that expresses itself in the phenotype is ___, while the one that is not expressed is ___? dominant, recessive 16 of 20 Give the names of the two different types of homzygous organisms based on the alles they have? homozygous dominant & homozygous recessive 17 of 20 The effect of the recessive allele is only apparent from the phenotype when..? In the presence of another identical allele (homozygous) 18 of 20 When are the alleles described as being co-dominant? When both alleles for one gene contribute to the phenotype of a heterozygous organism. 19 of 20 Give the term used to describe a gene that has more than two possible alleles? Multiple alleles (however only two of the alleles can be present in a single organism) 20 of 20
Comments
No comments have yet been made