Ch. 3 - Mendelian Genetics

Question 1

Terms to know: alleles

Answer 1

alternate forms or varieties of a gene.

The alleles for a trait occupy the same locus or position on homologous chromosomes and thus govern the same trait. However, because they are different, their action may result in different expressions of that trait.
amino acids click this icon to hear the preceding term pronounced

Question 2

Terms to know: carrier

Answer 2

an individual who is heterozygous for a trait that only shows up in the phenotype of those who are homozygous recessive.

Question 3

Terms to know: chromosomes vs chromatids

Answer 3

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Question 4

Terms to know: cross-fertilization, backcross, self-fertilization

Answer 4

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Question 5

Terms to know: dominant vs recessive allele

Answer 5

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Question 6

Terms to know: P generation, F1, F2, F3… generation

Answer 6

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Question 7

Terms to know: gene

Answer 7

units of inheritance usually occurring at specific locations, or loci, on a chromosome.

Physically, a gene is a sequence of DNA bases that specify the order of amino acids in an entire protein or, in some cases, a portion of a protein.

A gene may be made up of hundreds of thousands of DNA bases.

Genes are responsible for the hereditary traits in plants and animals.

Question 8

Terms to know: genotype

Answer 8

the genetic makeup of an individual

Genotype can refer to an organism’s entire genetic makeup or the alleles at a particular locus

Question 9

Terms to know: heterozygous vs homozygous

Answer 9

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Question 10

Terms to know: homologous chromosomes

Answer 10

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Question 11

Terms to know: hybrids (mono__, di__, tri__etc)

Answer 11

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Question 12

Terms to know: phenotype

Answer 12

the observable or detectable characteristics of an individual organism - the detectable expression of a genotype

Question 13

Terms to know: principle of independent assortment

Answer 13

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Question 14

Terms to know: principle of segregation

Answer 14

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Question 15

Terms to know: punnett square

Answer 15

a simple graphical method of showing all of the potential combinations of offspring genotypes that can occur and their probability given the parent genotypes.

Question 16

Terms to know: true breeding

Answer 16

offspring that are the result of mating between genetically similar kinds of parents - the opposite of hybrid.

Purebred is the same as true breeding.

Question 17

Terms to know: testcross

Answer 17

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Question 18

Terms to know: pedigree

Answer 18

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Question 19

Terms to know: autosomal

Answer 19

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Question 20

Terms to know: product rule vs sum rule

Answer 20

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Question 21

Terms to know: gametes

Answer 21

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Question 22

Terms to know: sperm

Answer 22

a male sex cell or gamete.

Question 23

Terms to know: ovum (plural ova)

Answer 23

a female sex cell or gamete.

Question 24

Terms to know: zygote

Answer 24

a “fertilized” ovum

More precisely, this is a cell that is formed when a sperm and an ovum combine their chromosomes at conception.

A zygote contains the full complement of chromosomes (in humans 46) and has the potential of developing into an entire organism.

Question 25

Who are the 3 scientists in this chapter and what did they contribute to genetics?

Answer 25

gregor mendel (1822 - 1884)
--> pea plant

walter sutton (1877 - 1916)
--> spermatogenesis in grasshoppers

Theodor Boveri (1864 - 1915)
--> sea urchins

Question 26

What analysis did Mendel carried out?

Answer 26

carried out quantitative analysis of pea pollination

• -> self-pollination
• -> cross-pollination

Question 27

Define self-pollination

Answer 27

pollen from stamens of a plant land on carpel of the same plant

Question 28

Define cross-pollination

Answer 28

pollen from a plant transferred to carpel of another plant

Question 29

What is Mendel’s model organism and what are its advantages?

Answer 29

peas

• -> easy to grow
• -> true-breeding strains
• -> controlled mating
• self-fertilization or cross-fertilization
• -> grow to maturity in one season
• -> observable characteristic with two distinct forms

Question 30

When did Mendel’s work published, which was essentially ignored, and rediscovered?

Answer 30

1866

1900

Question 31

What is monohybrid cross?

Answer 31

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Question 32

What were Mendel’s initial three postulate?

Answer 32

1. unit factors exist in pairs
   - -> genetic characters controlled by unit factors
2. dominance / recessiveness
   - -> in a pair of unit factors
   
   • -> one unit = dominant
   • -> the other = recessive
3. segregation
   - -> paired unit factors segregate (seperate) independently during gamete formation

Question 33

What is dihybrid cross?

Answer 33

• -> two pairs of contrasting trait

- -> generate unique F2 generation

Question 34

What is Mendel’s 4th postulate?

Answer 34

independent assortment

• -> unit factors (traits) assort independently during gamete formation
• -> all possible gamete combinations form with equal frequency

Question 35

What is the product law?

Answer 35

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Question 36

Describe chromosomal theory of inheritance.

Answer 36

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Question 37

What is trihybrid cross?

Answer 37

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Question 38

What is binomial theorem?

Answer 38

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Question 39

Chi-square and null hypothesis. What are they and how are they related?

Answer 39

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Question 40

What is pedigree?

Answer 40

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