Study Guide Unit 2 Part B 2010

8/8/2019 Study Guide Unit 2 Part B 2010

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Unit 2 Part B

Study Guide

2010


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Classical Genetics

Observable Patterns of Inheritance

Questions 1-13

Glossary terms Problem sets (2)


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Learn Terms

1. Learn the terms in the glossary,

Observable Patterns of Inheritance .

This is a word document.


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Q-1

1. An ear ly idea concerning inheritance was

the blending theory. What was it and

why was it deficient?


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A-1

1. An ear ly idea about inheritance was the

blending theory. What was it and why

was it deficient?

Traits from the male and female were

blended in the offspring.

If this were truth, then eventually, all

individuality would disappear.


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Q-2

What does the term locus mean?


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A-2

What does the term locus mean?

This is the location of a gene (whichchromosome and where on the

chromosome). Its address.


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Q-3

3. What are alleles?


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Answer 3

3. What are alleles?

These different molecular forms of thesame gene.


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Question 4

4. If two genes are homologous, what

does that mean?


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Answer 4

4. If two genes are homologous, what

does that mean?

Homologous means the same. They are

identical.


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Question 5

5. What does heterozygous mean?


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Answer 5

5. What does heterozygous mean?

Heterozygous means" different.Heterozygous for attached earlobes would

mean that the individual carries a normal

gene and a mutant gene.


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Question 6

6. If Sally is homozygous dominate for

gene A, how would you write that in

standard symbolic form? If she were

heterozygous for A? If she were

homozygous for the recessive form of A?


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Answer 6

6. If Sally were (a) homozygous dominate

for gene A, how would you write that in

standard symbolic form? (b) If she were

heterozygous for A? (c) If she were

homozygous for the recessive form of A?

AA,Aa, aa


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Question 7

7. Define phenotype.


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Answer 7

7. Define phenotype.

Phenotype refers to an individualsobservable traits


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Question 8

8. Define genotype.


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Answer 8

8. Define genotype.

Genotype refers to particular genes anindividual carries


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Question 9

9. How do you represent the first

generation of a cross?


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Answer 9

9. How do you represent the first

generation of a cross? Parental cross?

Second generation?

F1; P;F2


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Question 10

10. What is monohybrid cross (how many

traits are being investigated)?


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Answer 10

10. What is monohybrid cross (how manytraits are being investigated)?

It is a cross where two true breedingindividuals are mated (AA x aa). Usuallythey are homozygous dominant and

homozygous recessive. One trait (twoalleles).


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Question 11

11. Describe or define: dihybrid cross.


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Answer 11

11. Describe or define: dihybrid cross.

Experimental cross between individuals

that are homozygous for differentversions of two traits

Example:

AABB x aabb


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Question 12.

12. What three types of dominance?


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Question 12. What three types of

dominance?

12. What three types of dominance?

Complete dominance

Incomplete dominance

Codominance


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Question 13.

13. Define pleiotrophy.


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Answer 13

13. Define pleiotrophy.

Alleles at a single locus may haveeffects on two or more traits

Examples: Marfans syndrome and

Sickle CellAnemia


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Problem Sets

Go to:

http://www.biology.arizona.edu/mendelian

_genetics/mendelian_genetics.htm

l

Answer the two problem sets:

MonohybridCross and DihybridCross.


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Learn the Terms

Learn the terms in the glossary,

Observable Patterns of Inheritance .


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Chromosomes and Human

Genetics

Questions 1-20

Problem Set: Sex Linkage

Problem Set: Karyotyping Glossary: Chromosomes and Human

Genetics


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Q-1

1. The first abnormal chromosome tied to

cancer was named the ________

chromosome.


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A-1

1. The first abnormal chromosome tied to

cancer was named the _Philadelphia

_______ chromosome.


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Q-2

2. A ________ is a preparation of

metaphase chromosomes based on their

defining features.


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A-2

2. A __karyotype________ is a preparation

of metaphase chromosomes based on

their defining features.


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Q-3

3. The units of information about

heritable traits are known as ________.


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A-3

3. The units of information about heritable

traits are known as __genes________.


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Q-4

4. Diploid (2n) cells have pairs

of________ chromosomes.


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A-4

4. Diploid (2n) cells have pairs of

__homologous (sister)________

chromosomes.


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Q-5

5. _______ are different molecular forms

of the same gene that are possible at a

given locus; a ________-type allele is

the most common form of a gene.


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A-5

5. ___Alleles_______ are different

molecular forms of the same gene that are

possible at a given locus; a

__dominant________-type allele is the

most common form of a gene.


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Q-6

6. State the circumstances required for

crossing over and describe the results.


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A-6

6. State the circumstances required for

crossing over and describe the results.

Genes must be on the same

chromosome and afterCO, there will be

a new combination of maternal and

paternal mix of genes on the same

chromosome


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Q-7

7. Name and describe the sex

chromosomes in human males and

females.


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A-7

7. Name and describe the sex

chromosomes in human males and

females. XX(female); XY(male)


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Q-8

8. Human X and Y chromosomes fall into

the more general category of ________

chromosomes; all other chromosomes in

an individuals cells are the same in both

sexes and are called ________.


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A-8

8. Human X and Y chromosomes fall into

the more general category of

__sex________ chromosomes; all other

chromosomes in an individuals cells are

the same in both sexes and are called

__autosomes________.


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Q-9

9. Define karyotype; briefly describe its

preparation and value.


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A-9

9. Define karyotype; briefly describe its

preparation and value. A metaphase

preparation of chromosomal images

where the chromosomes are aligned in

groups (Largest to smallest)


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Q-10

10. Explain meiotic segregation of sex

chromosomes to gametes and the

subsequent random fertilization that

determines sex in many organisms.


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A-10

10. Explain meiotic segregation of sex

chromosomes to gametes and the subsequent

random fertilization that determines sex in many

organisms. XandYchromosomes are sisterchromosomes. In a female, each gamete can

only receive a X; in the male each gamete

has a 50: 50 chance of receiving an Y

chromosome. Thus the male determines thegender of the individual offspring.


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Q-11

11. A newly identified region of the Y

chromosome called __________ appears

to be the master gene for sex

determination. All the genes on a specific

chromosome are called a __________

group.


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A-11

11. A newly identified region of the Y

chromosome called ___SRY

region_______ appears to be the master

gene for sex determination. All the genes

on a specific chromosome are called a

__linkage________ group.


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Q-12

12. Explain why the term "sex-linked

genes" is less precise than the use of the

terms, X-linkedand Y-linked genes.


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A-12

12. Explain why the term "sex-linked

genes" is less precise than the use of the

terms, X-linkedand Y-linked genes. The

SRYregion is on the Ychromosome

(most of the time) and thus is linked to

the chromosome not just to a small

group of genes.)


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Q-13

13. State the relationship between

crossover frequency and the location of

genes on a chromosome.


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A-13

13. State the relationship between

crossover frequency and the location of

genes on a chromosome. The closer the

linkage, the lower the crossover rate.


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Q-14

14. ________ is a chart of the geneticconnections between individuals; be familiarwith the standardized symbols used in suchcharts.

A genetic ________ is a rare, uncommonversion of a trait whereas an inherited genetic

_________ is an inherited condition thatsooner orlater will cause mild to severe

medical problems.

A ________ is a recognized set of symptomsthat characterize a given disorder.


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A-14

14. __ Pedigree________ is a chart of thegenetic connections between individuals; befamiliar with the standardized symbols used insuch charts.

A genetic __abnormality________ is a rare,uncommon version of a trait whereas aninherited genetic _disorder_________ is aninherited condition that sooner orlater will cause

mild to severe medical problems.

A __ syndrome________ is a recognized set ofsymptoms that characterize a given disorder.


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Q-15

15. Describe what is meant by a genetic

disease.


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A-15

15. Describe what is meant by a genetic

disease. It is an inherited condition that

sooner or later will cause mild to

severe medical problems.


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Q-16

16. Describe the characteristics of

Hutchinson-Gilford progeria syndrome.


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A-16

16. Describe the characteristics of

Hutchinson-Gilford progeria syndrome.

Early progressive aging such that the

individuals are biologically aged at themid-teens. Dominant, random mutation.


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Q-17

17. A(n) ________ is a loss of achromosome segment; a(n) _________is a gene sequence separated from a

chromosome but then was inserted atthe same place, but in reverse; a(n)________ is a repeat of several genesequences on the same chromosome;

a(n) _________ is the transfer of part ofone chromosome to a nonhomologouschromosome.


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A-17

17. A(n) __deletion________ is a loss of a

chromosome segment; a(n)

_inversion_________ is a gene sequence

separated from a chromosome but then wasinserted at the same place, but in reverse; a(n)

__duplication________ is a repeat of several

gene sequences on the same chromosome; a(n)

_translocation_________ is the transfer of partof one chromosome to a nonhomologous

chromosome.


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Q-18

18. When gametes or cells of an affected

individual end up with one extra or one less

than the parental number of chromosomes, it

is known as _______; relate this concept tomonosomy and trisomy.

Having three or more complete sets of

chromosomes is called ________.

________ is the failure of the chromosomes toseparate in either meiosis or mitosis.


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A-18

18. When gametes or cells of an affectedindividual end up with one extra or one less thanthe parental number of chromosomes, it isknown as ___aneuploidy_______; relate thisconcept to monosomy and trisomy.

Having three or more complete sets ofchromosomes is called __trisomy________.

__nondisjunction________ is the failure of thechromosomes to separate in either meiosis ormitosis.


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Q-19

19. Trisomy 21 is known as _______

syndrome; Turner syndrome has the

chromosome constitution, ________;

XXY chromosome constitution is_________ syndrome; taller than

average males with sometimes mild

mental impairment have the ________condition.


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A-19

19. Trisomy 21 is known as

__Downs_______ syndrome; Turner

syndrome has the chromosome

constitution, __of 45________; XXYchromosome constitution is

_Klinefelters_________ syndrome; taller

than average males with sometimes mildmental impairment have the

__XYY________ condition.


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Q-20

20. List some benefits of genetic screening

and genetic counseling to society.


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A-20

20. List some benefits of genetic screeningand genetic counseling to society.

Principally, an afflicted individual could

get immediate medical attention tomanage the genetic medical problem(s)associated with the genotype. Othersmay feel that a pregnancy should be

terminated if the fetus has a seriousgenetic problem.


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Problem Set, Sex Linkage

Go to:

http://www.biology.arizona.edu/mende

lian_genetics/mendelian_genetics.html

Do the problem set: Sex

LinkedInheritance 1


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Problem Set: Karyotying

Go to:

http://www.biology.arizona.edu/mende

lian_genetics/mendelian_genetics.html

Do the problem set: Karyotyping Activity

Documents

Study Guide Unit 2 Part B 2010