Genetics: Transmission Genetics chap 2

Question 1

Transmission genetics

Answer 1

the field that describes and investigates the patterns of transmission of genes and traits from parents to offspring

Question 2

Features that made Mendel’s experiments different from those of his contemporaries were?

Answer 2

1) Controlled crosses between plants
2) Use of pure-breeding strains to begin the experimental controlled crosses
3) Selection of dichotomous traits
4) Quantification of results
5) Use of replicate, reciprocal, and test crosses

Question 3

P generation

Answer 3

Parental generation

Question 4

F1 generation

Answer 4

First filial generation

Question 5

F2 generation

Answer 5

Second filial generation

Question 6

Reciprocal crosses

Answer 6

Same genotypes,as the one from the first cross, are crossed but the sexes of the donating parents are switched

Question 7

Test crosses

Answer 7

When an individual with certain genes is crossed with a recessive individual to figure out the gene to figure out the gene of the first individual

Question 8

Monohybrid crosses

Answer 8

cross between individuals with different variation at one gene
A term referring to a cross between two organisms that have the same heterozygous genotype for one gene

Question 9

Dominant phenotype

Answer 9

Strongly expressed phenotype

Question 10

Recessive phenotype

Answer 10

usually the carriers phenotype

Question 11

what is the phenotypic ration for a Monohybrid cross between two homozygous parents? What is the ration of a gamete self-fertilization of the F1 or cross between two F1 from that cross? What is the genotypic rations of this latter

Answer 11

1

3: 1
1: 2:1

Question 12

Blending theory of heredity

Answer 12

It is a theory saying that offspring inherited their traits from intermediate characteristics of their parents

Question 13

Alleles

Answer 13

Hereditary particles that are passed form generation to the next

Question 14

Allele

Answer 14

a form of a gene that exists at

A single locus

Question 15

Locus

Answer 15

place on a chromosome where the gene is located

Question 16

Genotype

Answer 16

allelic composition of the cell or organism

Question 17

Phenotype

Answer 17

an inherited characteristic

Question 18

Homozygous genotype

Answer 18

Organism is carrying two identical alleles

ex: gg, GG,rr,RR

Question 19

Heterozygous genotype

Answer 19

Organism is carrying two different alleles

ex: Gg,Rr

Question 20

Punnett square

Answer 20

Method of diagramming a genetic cross is a simple tool of genetic analysis
The alleles ( in gametes) carried by one parent are arranged along the top of the square and those of the other parent, down the side
The results expected from random fusion of the gametes are placed within the square

Question 21

Law of segregation

Answer 21

It is also known as Mendel’s first law
It says: The two alleles for each trait will segregate ( separate) from one another during gamete formation , and each allele will have an equal probability (1/2) of inclusion in a gamete. Random union of the gametes at fertilization will unite one gamete from each parent to produce progeny in ratios ha are determined by chance

Question 22

Gene

Answer 22

A gene is the basic unit of inheritance

Question 23

Trait aka phonotype

Answer 23

an inherited charatecrisic

Question 24

Dihybrid crosses

Answer 24

Crosses between organisms that differ for two traits.
Ex: mono= trait is color gg X GG
Di= Traits are color and shape RRggXrrGG

Question 25

Law of independent assortment

Answer 25

Also called Mendel's law of independent assortment During gamete formation, the segregation of alleles at one gene is independent of the segregatio of alleles at another gene

Question 26

Law of independent assortment

Answer 26

Also called Mendel's law of independent assortment During gamete formation, the segregation of alleles at one gene is independent of the segregation of alleles at another gene. The units of inheritance( genes) come in pairs:- each gamete will get only one of the units of inheritance -The progeny then gets one maternal and one paternal copy

Question 27

Trihybrid cross

Answer 27

a cross involving three traits

Question 28

2^n

Answer 28

It is used to know the number of different gamete genotypes

Question 29

The phenotypic ratio for a trihybrid cross ( coming from a self-fertilization of F1 from a cross between two homozygous parents)

Answer 29

27:9:9:3:9:3:1

Question 30

The product rule

Answer 30

Multiplication rule | Use: "And"

Question 31

The Sum rule

Answer 31

Addition rule | Use "Or"

Question 32

Conditional probability

Answer 32

Applied when specific information about the outcome modifies, or "conditions"

Question 33

Forward Genetics

Answer 33

1) Begin with a biological question 2) Identify genetic variation (phenotype) that effects your question 3) Identify the cause of the variation 4) that gene is therefore involved in the biological function

Question 34

Reverse Genetics

Answer 34

start with the gene sequence and works backward to the mutant phenotype Gene of interest->Mutate GOI->Analyze phenotype

Question 35

The basis for segregation and independent assortment is

Answer 35

meiosis

Question 36

Reciprocal crosses

Answer 36

Reciprocal crosses between pure-breeding parents produce identical results

Question 37

Chi-square test

Answer 37

It's a test that determines the probabilty that a difference is caused by chance

Question 38

Chi-square test

Answer 38

It's a test that determines the probability that a difference is caused by chance

Question 39

Null hypothesis

Answer 39

the hypothesis that there is no significant difference between specified populations, any observed difference being due to sampling or experimental error.

Question 40

To know about ch square test

Answer 40

If the value of p>0.05, it means that fail to reject the chance hypothesis( we accept the null hypothesis), in other words, the differences between the observed value and the expected value are caused due chance. If the value of p<0.05, it means that we reject the chance hypothesis ( we reject the null hypothesis); in other words the difference between the value observed and the expected value are not caused by chance, therefore, the initial hypothesis is incorrect

Question 41

Rules of inheritance

Answer 41

The units of inheritance( genes) come in pairs Each gamete will get only one of the two units of inheritance. The progeny then gets one maternal and one paternal copy The segregation of one gene pair is most often independent of the segregation of another gene pair- independent assortment

Question 42

Why is free chromosomal assortment biologically great?

Answer 42

because genotypes created are different from the parental ones New and more vigorous strains can be formed Diversity enhances he chance that under changed environmental conditions some individuals will be better adapter and will survive---> basis for evolution

Question 43

Sex-linked inheritance

Answer 43

Reciprocal crosses give different results | Male and female progeny and ratios are different

Question 44

Autosomal inheritance

Answer 44

The transmission that are carried on autosomes, the chromosomes (22 pairs in humans) that are not sex chromosomes ( X and Y chromosomes)

Question 45

Pedigrees

Answer 45

Family trees A kind of symbolic shorthand used to trace the inheritance of traits in humans and in animals such as horses, dogs,cats, cattle, and others.

Question 46

Autosomal dominant inheritance key features

Answer 46

1) Each individual who has the disease has at least one affected parent 2) Males and females are affected in equal numbers 3) Either gender can transmit the disease allele 4) In crosses where one parent is affected and the other is not, approximately half the offspring express the disease 5) Two unaffected parents will not have any children with the disease 6)Two affected parents may produce unaffected children

Question 47

Autosomal recessive inheritance key features

Answer 47

1) Individuals who have the disease are often born to parents who do not 2) If only one parent has the disorder, the risk that a child will have it depends on the genotype of the other parent 3) If both parents have the disorder, all children will have it 4) The sex ratio of affected offspring is expected to be equal 5) The disease is not usually seen in each generation, but if an affected child is produced by unaffected parents, the risk to subsequent children is ¼ 6) If the disease is rare in the population, unaffected parents of affected children are more likely to be related to one another

Question 48

Hemophilia A

Answer 48

It is an X-linked recessive trait It is caused by mutation in the factor VIII gene on the X chromosome The mutant allele produces a nonfunctional blood-clotting protein A de novo( newly occuring) mutation is thought have been passed from Queen Victoria of England to some of her offspring

Question 49

Expression of X-linked recessive traits

Answer 49

A hallmark of recessive X-linked inheritance is the expression of the trait much more often in males than females Human have numerous X-linked recessive traits