Genetics and Evolution

Question 1

Homozygous

Answer 1

Describes a fertilized egg that receives the same allele from each parent for a particular trait

Question 2

Allele

Answer 2

An allele is an alternative form of a gene (one member of a pair) that is located at a specific position on a specific chromosome. These DNA codings determine distinct traits that can be passed on from parents to offspring.

Question 3

Heterozygous

Answer 3

Describes a fertilized egg that receives a different allele from each parent for the same trait

Question 4

Gene

Answer 4

portion or portions of the DNA molecule that code for proteins that shape phenotypic traits

Question 5

Chromosomes

Answer 5

Sets of paired bodies in the nucleus of cells that are made of DNA and contain the hereditary genetic information that organisms pass on to their offspring. Humans have 46

Question 6

Mitosis

Answer 6

The way body cells make copies of themselves. The pairs of chromosomes in the nucleus of the cell duplicate and line up along the center of the cell. The cell then divides, each daughter cell taking one full set of paired chromosomes.

Question 7

Meiosis

Answer 7

The way sex cells make copies of themselves, which begins like mitosis, with chromosomes duplication and the formation of two daughter cells. However, each daughter cell then divides again without chromosome duplication and, as a result, contains only a single set of chromosomes rather than the paired set typical of body cells.

Question 8

Locus

Answer 8

A portion of the DNA strand responsible for encoding specific parts of a organisms biological makeup

Question 9

Linkage

Answer 9

An inheritance pattern in which unrelated phenotypic traits regularly occur together because the genes responsible for those occurring traits are passed on together on the same chromosome.

Question 10

Crossing over

Answer 10

The phenomenon that occurs when a part of one chromosome breaks off and reattaches itself to a different chromosome during meiosis also called incomplete linkage.

Question 11

Genotype

Answer 11

Tells what the type is

Question 12

Phenotype

Answer 12

Shows the trait

Question 13

Pan-genesis

Answer 13

A theory of hereditary suggesting that an organisms physical traits are passed on from one generation to the next in the form of multiple distinct particles given off by all the parts of the organism, different proportions of which get passed on to the offspring via sperm or egg

Question 14

Polygeny

Answer 14

The phenomenon whereby many genes are responsible for producing a phenotypic trait, such as skin color

Question 15

Continuous variation

Answer 15

A pattern of variation involving polygeny in which phenotypic traits grade imperceptibly from one member of the population to another without sharp breaks

Question 16

Pleiotropy

Answer 16

The phenomenon whereby a single gene may affect more than one phenotypic trait

Question 17

Mutation

Answer 17

The creation of a new allele for a gene when the portion of the DNA molecule to which it corresponds is suddenly altered

Question 18

DNA

Answer 18

The structure that carries the genetic heritage of an organism as a kind of blueprint for the organisms construction and development

Question 19

Genome

Answer 19

The sum total of all the genetic information about an organism, carried on the chromosomes in the cell nucleus

Question 20

RNA

Answer 20

Controls how information is used
Single stranded
Uracil - one of the four nucleobases in the nucleic acid of RNA that are represented by the letters A, G, C and U.
Ribose

Question 21

Dominant Allele

Answer 21

Traits that mask the presence of other traits

Question 22

Recessive Allele

Answer 22

The masked trait

Question 23

Punnett Square

Answer 23

named after Reginald C. Punnett, who devised the approach, and is used by biologists to determine the probability of an offspring’s having a particular genotype.

Question 24

Gregor Mendell

Answer 24

Priest in Brno (Chech Republic) 29 got college degree. the founder of the new science of genetics. Mendel demonstrated that the inheritance of certain traits in pea plants follows particular patterns, now referred to as the laws of Mendelian inheritance

Question 25

Polygenetic traits

Answer 25

Reflects the activities of more than one gene 
Continuous variation
Examples:
Fingerprints 
eye color
hieght
skin color

Question 26

Heritability

Answer 26

the proportion of observable differences in a trait between individuals within a population that is due to genetic differences.

Question 27

Y Chromosome

Answer 27

Can trace male ancestry
Has few genes
Specific mutations can be used to group related males together in to haplotypes, die out in two generations

Question 28

Mitochondrial DNA

Answer 28

Can trace female ancestry through it

Question 29

Population Genetics

Answer 29

Developed in early 20th Century
Linked to Darwinian evolution and Mandellian inheritance. Looks at distribution of genetic alleles and genotypes across space and time. How do frequency of alleles change.

Question 30

Allele Frequency

Answer 30

the frequency of an Allele in a population

Question 31

Heterozygosity

Answer 31

Expected proportion of heterozygotes in the population vs actual. Tells us how diverse a population is.

Question 32

Hardy-Weinberg

Answer 32

(p+q)^2=1
Measures the change in allele frequency from one generation to another. states that both allele and genotype frequencies in a population remain constant—that is, they are in equilibrium—from generation to generation unless specific disturbing influences are introduced.

Question 33

Four forces of evolution

Answer 33

Mutation
Gene flow
Genetic drift
Natural selection

Question 34

Mutation types

Answer 34

Point - the replacement of a single base nucleotide with another nucleotide of the genetic material, DNA or RNA
Deletion - part of a chromosome or a sequence of DNA is missing. Deletion is the loss of genetic material
Insertion - addition of one or more nucleotide base pairs into a DNA sequence

Question 35

FST

Answer 35

The proportion of total variation that can be accounted for by between population differences

Question 36

Bottleneck

Answer 36

An event where a large portion of the population is prevented from reproducing

Question 37

Founders Affect

Answer 37

Allele frequencies in a small group of founders may be different (by chance) from their original population

Question 38

Natural Selection

Answer 38

where an organism best suited for an environment survives and passes on its genes

Question 39

Assortative Mating

Answer 39

where individuals with similar genotypes and/or phenotypes mate with one another more frequently than what would be expected. Doesn’t change the allele frequency but does increase homozygous individuals

Question 40

Dissortative Mating

Answer 40

Where opposites mate.