Chapter 8: Heredity

Question 0

Allele

Answer 0

On of the several varieties of a gene.

Question 1

Gene

Answer 1

Represents the genetic material on a chromosome that contains the instructions for creating a particular trait.

Question 2

Locus

Answer 2

The location on a chromosome where a gene is located.

Question 3

Mendel’s Law of Segregation

Answer 3

One member of each chromosome pair migrates to an opposite pole so that each gamete contains only one copy of each chromosome and allele.

Question 4

Test Cross

Answer 4

The mating of an individual whose genotype you are trying to determine with an individual whose genotype is known.

Question 5

Agglutination

Answer 5

Clumping

Question 6

Polygenic Inheritance

Answer 6

The interaction of many genes to shape a single phenotype.

Question 7

Linked Gnes

Answer 7

Genes that reside on the same chromosome and can’t split because they are connected

Question 8

Linkage Map

Answer 8

A portrayal of the sequence of genes on a chromosome

Question 9

Cytological Map

Answer 9

A map portraying the true relative positions of the genes

Question 10

Barr Body

Answer 10

A coiled, dark, compact x-chromosome.

Question 11

Nondisjunction

Answer 11

The failure of one or more chromosome pairs or chromatids of a single chromosome to properly move to opposite poles during meiosis or mitosis.

Question 12

Mosaicism

Answer 12

Result of nondisjunction. When a faction of the body cells that are descendent of a cell where nondisjunction occurs have an extra or missing chromosome.

Question 13

Polyploidy

Answer 13

Occurs if all of the chromosomes undergo meiotic nondisjunction and produce gametes with twice the number of chromosomes.

Question 14

Point Mutations

Answer 14

Occur when a single nucleotide in the DNA of a gene is incorrect.

Question 15

Substitution

Answer 15

When a different nucleotide is substituted for the correct one.

Question 16

Deletion

Answer 16

When the nucleotide base pair is omitted

Question 17

Insertion

Answer 17

If an extra base-pair is inserted

Question 18

Sickle-cell disease

Answer 18

Caused by Nucleotide substitution. Results in the production of defective haemoglobin.
Sickle Cell shaped RBC when O2 is limited. Leads to organ damage, bone abnormalities, and impaired mental functioning.

Question 19

Tay-Sachs Disease

Answer 19

Caused by nucleotide insertion. Results when lysosomes lack the functional enzyme to break down certain fats.
Fats accumulate in nerve cells of the brain, brain cells die.

Question 20

Aneuploidy

Answer 20

A genome with extra or missing chromosomes.

Often Caused by non-disjunction.

Question 21

Down Syndrome

Answer 21

Example of Aneuploidy.

Occurs when an egg or sperm with an extra number 21 chromosome fuses with a normal gamete.

Question 22

Turner Syndrome

Answer 22

Results when there is nondisjunction of the sex chromosomes. Sperm will be either XY or O(No sex chromosomes), and eggs will be either XX or O.
XO= Sterile Female with physical abnormalities.
Missing Y chromosome= Dead, or happily alive male

Question 23

Klinefelter Syndrome

Answer 23

Occurs when an XY or XX gamete, produced as a result of nondisjunction, combines with a normal X gamete to produce an XXY individual.
XXY individual= Sterile, may experience female secondary sex characteristics.
XXX= Female, often few problems.

Question 24

Chromosomal Aberrations

Answer 24

Caused when chromosome segments are changed.

Question 25

Duplications

Answer 25

When a chromosome segment is repeated on the same chromosome.

Question 26

Huntington’s Disease

Answer 26

Caused by the insertion of multiple repeats of three nucleotides.
The mutant gene codes for a defective enzyme, which results in the death of nerve cells in the brain.

Question 27

Inversions

Answer 27

When chromosome segments are rearranged in reverse orientation on the same chromosome.

Question 28

Translocaitons

Answer 28

Occur when a segment of a chromosome is moved to another chromosome.

Question 29

Maternal Inheritance

Answer 29

Can be used to trace a specific genome from progeny back through multiple generations to its original mother.