Definitions

Question 1

Define genotype

Answer 1

the genetic information carried by a pair of alleles, which determines a particular characteristic

Question 2

Define phenotype

Answer 2

the observable characteristic of an individual, which results from an interaction between the genotype and environment

Question 3

Define allele

Answer 3

1 or more alternatives of a gene at a specific locus, only one of which can be present in the chromosome

Question 4

Define polymorphism

Answer 4

the occurrence of a chromosome in more than one form, resulting in the coexistence of more than one morphological type in the same population

Question 5

Define gene

Answer 5

a segment of DNA that contains the biological instructions for a particular polypeptide

Question 6

Define penetrance

Answer 6

the frequency to which the characteristic controlled by a gene is seen in individuals possessing it.
complete penetrance if all with gene have characteristic

Question 7

Define hemizygous

Answer 7

genes that are carried on an unpaired chromosome, e.g. X in XY

Question 8

Define autosome

Answer 8

any chromosome that’s not a sex chromosome and appears in pairs

Question 9

Define allelic heterogeneity

Answer 9

different mutations within the same gene result in the same clinical condition, e.g. CF

Question 10

Define consanguinity

Answer 10

relationship by blood, e.g. common ancestor

Question 11

Define mosaicism

Answer 11

a condition in which the cells of an individual do not all contain identical chromosomes, e.g. somatic mosaicism- genetic fault in some tissues

Question 12

Define locus heterogeneity

Answer 12

variants in different genes give the same clinical condition, e.g. hypertrophic cardiomyopathy

Question 13

Define anabolic

Answer 13

promoting tissue growth by increasing the metabolic processes involved in protein synthesis

Question 14

Define catabolism

Answer 14

chemical decomposition of complex substances to form simpler ones and release energy, e.g. Krebs

Question 15

Define BMR

Answer 15

basal metabolic rate
the minimum amount of energy expended by the body to maintain vital processes

Question 16

Define malnutrition

Answer 16

a condition where there is an imbalance between the nutrients the body receives and the nutrients it requires

Question 17

Define anticipation

Answer 17

Genetic disorder affects successive generations earlier/ more severely due to expansion of unstable triplet repeat
E.g. myotonic dystrophy

Question 18

Define homoplasmy

Answer 18

a eukaryotic cell whose copies of mitochondrial DNA are identical

Question 19

Define heteroplasmy

Answer 19

multiple copies of mitochondrial DNA in each cell
level can vary between cells in the same tissue or organ

Question 20

Define osmosis

Answer 20

Movement of water across a membrane down its concentration gradient, towards the area of higher solute concentration

Question 21

Define osmotic pressure