Chapter 13, 14

Question 1

what are genes?

Answer 1

Gene in an organism ‘s specific locus on a certain chromosome.

Question 2

what are genes?

Answer 2

Gene in an organism ‘s specific locus on a certain chromosomes

Question 3

What is an karyotype

Answer 3

The resulting ordered displayed for chromosomes.

Question 4

What is an karyotype

Answer 4

The resulting ordered displayed

Question 5

What is a sexual reproduction?

Answer 5

Combines sets of genes from two different parents, leading to genetically diverse offspring.

Question 6

What Are diploid?

Answer 6

Normal human somatic cell are diploid. They have 46 chromosomes made up of two sets of 23 - one set from each parent.

Question 7

What are in an human diploid cell?

Answer 7

22 homologous pairs of autosomes each with a maternal and paternal homolog.

Question 8

What is an sex chromosome?

Answer 8

The 23rd pair determines whether the person is a female (XX) or male (XY).

Question 9

What occurs in a sexual maturity life cycle?

Answer 9

Ovaries and Testes (the gonads) produce haploid gametes by meiosis each gamete containing single set 23 chromosomes.

Question 10

What occurs during fertilization?

Answer 10

An egg and sperm unite, forming a multicellular organism by mitosis.

Question 11

How is a zygote form?

Answer 11

Egg and sperm unite producing an diploid, which develops into a multicellular organism by mitosis.

Question 12

What occurs in meiosis?

Answer 12

meiosis reduces the number of chromosome sets from diploid to haploid.

Question 13

What occurs in meiosis 1 and meiosis 2?

Answer 13

produce four haploid daughter cells

Question 14

How is meiosis distinguished from mitosis in 3 events of meiosis?

Answer 14

> Prophase I: Each homologous pair undergoes synapsis and crossing over between non sister chromatids with subsequent appearance of chiasmata.
Metaphase1 : Chromosomes line up as homologous pairs on the metaphase plate.
Anaphase 1: Homologs separate from each other; sister chromatids remain joined at centromere.

Question 15

What happens in Meiosis 2?

Answer 15

sister chromatids separate

Question 16

What happens in Meiosis 2?

Answer 16

sister chromatids seperate

Question 17

What are the three events in a sexual reproduction to contribute to genetic variation in a population?

Answer 17

> independent assortment of chromosomes during meiosis
Crossing over during meiosis1
random fertilization

Question 18

What occurs in recombinant chromosomes?

Answer 18

When crossing over involves breakage and rejoining of DNA of nonsister chromatids in homologous pair result in recombinant chromatids that will become recombinant chromosomes.

Question 19

What is law of segregation?

Answer 19

It is stated that genes have alternative forms of alleles. in diploid organism, the two alleles of gene separate during meiosis and gamete formation each sperm or egg carries only one allele of each pair.

Question 20

What is heterozygotes?

Answer 20

The two alleles are different, expression of one dominant and recessive one that mask phenotypic effect of the other.

Question 21

What is heterozygotes?

Answer 21

The two alleles are different, expression of one dominant allele.

Question 22

What are homozygotes?

Answer 22

identical alleles of a given gene that are true breeding.

Question 23

What is the law of independent assortment?

Answer 23

States that pairs of alleles for a given gene separates into gametes independently of the pairs of alleles of any other gene. In a cross between individuals heterozygous for genes, the off spring have four phenotypes in 9:3:3:1 ratio.

Question 24

What are the laws of probability govern mendelian inheritance?

Answer 24

Multiplication rule: states that the probability of two or more events occurring together is equal to the product of the individual of the independent single events.
Addition rule: states that probability of an event that can occur in two or more independent, mutually exclusive ways is sum of the individual probabilities.

Question 25

What is an Complete dominance of one allele

Answer 25

: Heterozygous phenotype same as that homo zygous dominant.

EX: Flower’s dominant color.

Question 26

What is an incomplete dominance of either allele?

Answer 26

Heterozygotes phenotype intermediate between the two homozygous phenotypes.
EX: The pink flower is in the middle of two phenotypes.

Question 27

Codomiance

Answer 27

Both phenotypes expressed in heterozygotes.

EX: Blood types A and B

Question 28

What is an Pleiotrophy?

Answer 28

One gene is able to affect multiple phenotypic characters. EX: sickle cell

Question 29

What is an Pleiotrophy?

Answer 29

One gene is able to affect multiple phenotypic characters. EX: sickle.

Question 30

What is an Epistasis?

Answer 30

The phenotypic expression of one gene affects that one another.

Question 31

Polygenic inheritance ?

Answer 31

A Single phenotypic character is affected by two or more genes.

Question 32

What is an norm of reaction ?

Answer 32

The expression of genotype can be affected by environmental influences, the “nurture”. in nature verse nurture. the phenotypic range of a particular genotype.

Question 33

What is an multifactorial?

Answer 33

Polygenic characters that are also influenced by the environment.

Question 34

What is an analysis of family pedigrees?

Answer 34

It is used to deduce the possible genotypes of individuals and make predictions about future offspring. Predictions are statistical probabilities rather than certainties.

Question 35

What are carriers?

Answer 35

Most affected homo recessive individuals are children of phenotypically normal, heterozygous.

Question 36

What are the ways to test recessive alleles associated with disorders.

Answer 36

Amniocentesis and chorionic villus sampling.