Lesson 3, Chapter 5

Question 1

The Principle of Segregation

Answer 1

In the process of sex cell formation, each pair of chromosomes received from both parents of an individual separates.

Question 2

The Principle of Independent Assortment

Answer 2

Each pair of chromosomes passes on to the offspring independent of the other ones.

Question 3

Duchenne’s muscular dystrophy

Answer 3

A sex-linked disorder that causes the deterioration of muscle tissue.

Question 4

Cystic fibrosis

Answer 4

A recessive disorder that causes the production of thick, sticky mucus.

Question 5

Mutations

Answer 5

Changes in the sequences of nucleotides in the DNA that makes up a gene.

Question 6

Sickle cell disease

Answer 6

A recessive disorder that causes red blood cells to be sickle-shaped.

Question 7

Indels

Answer 7

The addition or deletion of base pairs when genetic material is copied during DNA replication.

Question 8

Fragile X-syndrome

Answer 8

A genetic disorder caused by repetitions of the triplet CGG over and over in the X sex chromosome.

Question 9

Chromosomal mutations

Answer 9

Mutations that involve long segments of a DNA molecule.

Question 10

Deletion

Answer 10

A chromosomal mutation where parts of a chromosome are missing.

Question 11

Williams syndrome

Answer 11

A genetic disorder caused by a small deletion on the arm of one of the chromosomes in the 7th pair, resulting in circulatory system and other disorders.

Question 12

Insertion

Answer 12

A chromosomal mutation where chromosomal material breaks off a chromosome and reinserts itself on the same chromosome or on another chromosome.

Question 13

Inversion

Answer 13

A type of insertion where the genetic material breaks off and is then reinserted upside down.

Question 14

Translocation

Answer 14

A type of insertion where genetic material breaks off and is then reinserted in a different chromosome.

Question 15

Walker-Warburg syndrome

Answer 15

A syndrome caused by an inversion mutation in chromosome 9 which causes abnormalities in the muscles, brains, and eyes .

Question 16

Nondisjunction

Answer 16

The failure of homologous chromosomes to separate properly during meiosis so that one sex cell gets an extra chromosome, and another sex cell is missing a chromosome.

Question 17

Monosomy

Answer 17

Cells missing a chromosome.

Question 18

Trisomy

Answer 18

Cells having one too many chromosomes.

Question 19

Turner syndrome

Answer 19

A genetic disorder where females have just one X on their 23rd pair of chromosomes causing a lack of development of secondary sex characteristics.

Question 20

Karyotype

Answer 20

A photograph, taken when chromosomes are condensed, rearranged to show the pairs of chromosomes in order of their size.

Question 21

Trisomy 21 (Down syndrome)

Answer 21

A genetic disorder where there are three 21 chromosomes instead of two causing mental retardation, a short stature, characteristic facial features, and heart defects.