Quiz 1

Question 1

Locus

Answer 1

A fixed position on a chromosome where a particular gene or genetic marker is located. The plural form of this term is loci.

Question 2

Gene

Answer 2

The basic physical and functional unit of heredity which is transferred from parent to offspring. It is also a sequence of DNA on a particular locus of a chromosome. In genes that code for proteins, the DNA comprising that gene directs the synthesis of the protein.

Question 3

Protein

Answer 3

Molecules that carry out a variety of functions within a cell.

Question 4

Chromosome

Answer 4

A physical structure that stores genetic information, which is composed of long strands of DNA coiled around proteins. It is a threadlike structure that resides in the nucleus of the cell.

Question 5

Allele

Answer 5

The alternate form or versions of a gene. People inherit one allele for each autosomal gene from each parent, and we tend to lump the alleles into categories. Typically, we call them either normal or wild-type alleles, or abnormal, or mutant alleles.

Question 6

Polymorphism/mutation

Answer 6

The occurrence of two or more sequence variants at a particular DNA sequence that can occur between different individuals or populations.

Question 7

Wild type

Answer 7

The wild type version of a gene, or the wild type allele, is an allele that existed before a mutation occurred within the population.

Question 8

Complex trait

Answer 8

Also known as quantitative traits, are traits that do not behave according to simple Mendelian inheritance laws. They are believed to result from variation within multiple genes and their interaction with environmental influence. An example of these traits is height.

Question 9

Polygenic vs monogenic

Answer 9

Polygenic refers to traits that are influenced by two or more genes, and are responsible for attributes such as height. These traits do not follow the typical law of Mendelian inheritance. Monogenic, in contrast, are the product of a single gene or allele, such as eye color.

Question 10

Genotype

Answer 10

The genetic makeup of an organism

Question 11

Phenotype

Answer 11

Observable expression of a genotype, a person’s presentation

Question 12

Haploid vs Diploid

Answer 12

Haploid refers to the presence of a single set of chromosomes in an organism’s cell. Diploid refers to the presence of two complete sets of chromosomes in an organism’s cells, with one parent contributing a chromosome to each pair. Humans and other sexually reproducing organisms contain diploid cells, while asexual organisms such as bacteria contain haploid cells.

Question 13

Hemizygous

Answer 13

This is when only one chromosome of a chromosome pair is observed (ex. The X and Y chromosomes in males are each Hemizygous, as the genes on each chromosome only appear once)

Question 14

Meiosis

Answer 14

A cell creates 4 haploid gametes that are used in sexual reproduction

Question 15

Mitosis

Answer 15

Asexual reproduction, where a cell makes an exact copy of itself

Question 16

Autosomal vs Sex linked

Answer 16

Autosomal traits are genes that are located on any chromosomes that are not the X or Y sex chromosome, where as Sex Linked traits are those located on the X and Y chromosome

Question 17

Homozygous

Answer 17

Refers to having inherited the same versions of alleles from each biological parent.

Question 18

Heterozygous

Answer 18

Refers to having different alleles for a particular trait. The relationship between the two alleles affects how the traits are expressed.

Question 19

Dominant vs recessive genes

Answer 19

An allele of a gene is said to be dominant when it effectively overrules the other recessive allele. Dominant alleles produces dominant phenotypes. For a recessive allele, to produce a recessive phenotype the individual must receive two copies, Oms from each parent

Question 20

Codominant

Answer 20

Both alleles are expressed entirely in different parts of an organism. eg. calico cats

Question 21

Incomplete dominance

Answer 21

Neither allele expresses it’s phenotype completely, but the 2 phenotypes blend. eg. a white flower and red flower breed and create a pink flower

Question 22

Continuous Characteristic

Answer 22

Infinite number of possibilities(i.e. height) , often follows something that looks like a normal distribution curve

Question 23

Meristics Characteristics

Answer 23

Characteristic you can count (has to be an integer), often will form a normal distribution curve when looking at a population (i.e. how many kittens were born in a liter)

Question 24

Threshold

Answer 24

Have an underlying normal distribution, but we set thresholds within the distribution to measure certain individuals

Question 25

VP= VG+VE

Answer 25

VP = Phenotypic variance
VG = Genetic variance
VE = Environmental variance

Question 26

What are the three genetic variance subsets?

Answer 26

Additive, dominance, epistasis

Question 27

VE = VG * E

Answer 27

VE = Environment variance
VG = Genetic variance
E = Environment

Question 28

Additive Genetic Variance

Answer 28

Behaves in additive manner, brighter color = more of the same allele

Question 29

Dominance Genetic Variance

Answer 29

Determination due to dominant allele

Question 30

Epistasis Genetic Variance

Answer 30

Multiple loci interacting with one another, labrador retriever example

Question 31

Broad Sense Heritability

Answer 31

H^2=VG/VP
H = Heritability
Shows proportion of phenotypic variance due to genetics variance

Question 32

Narrow sense Heritability

Answer 32

h^2=VA/VP
Shows proportion of phenotypic variance due to additive genetic effects