Unit 7

Question 1

 abnormal chromosome number within the cell or organism that results from presence or absence of one or more extra chromosome in the cells

Answer 1

Aneuploidy

Question 2

What are three examples of autosomal aneuploidies?

Answer 2

Down syndrome trisomy 21, trisomy 18, trisomy 13

Question 3

Three examples of sex-chromosome aneuplodies

Answer 3

Turner syndrome, Jacobs syndrome

Question 4

The condition in which an organism or cell having more than double the haploid number of chromosomes

Answer 4

Polyploidy

-multiple chromosomes sets from the genetic material within the cell can be lethal in humans

Question 5

triploid (3N) and tetraploid (4N) are examples of…..

Answer 5

Polyploidy

Question 6

the failure of the chromosomes to separate, which produces daughter cells with abnormal numbers of chromosomes.

Answer 6

Non-disjunction

Question 7

In meiosis, chromosomal nondisjunction may occur during the ___________ meiotic division, and result in formation of gametes, which contain an extra chromosome, or extra set of chromosomes.

Answer 7

1st or 2nd

Question 8

In rare cases, chromosomal nondisjunction may occur in ___________ of mitosis and result in establishment of a clone of abnormal daughter cells in a normal organism.

Answer 8

Anaphase

Question 9

What can cause abnormalities in chromosomal number (aneuploidy or polyploidy) in fertilization?

Answer 9

One egg fertilized by more than one sperm

Question 10

Chromosomal damage may be caused by exposure to some mutagenic agent such as…

Answer 10

-environmental factors
-Chemical modifiers
-base analogues
-radiation

Question 11

Abnormalities in chromosomal structure may also result from genetic chromosomal instability due to exposure to mobile genetic elements. Mechanisms are classified into…

Answer 11

-fragile sight by nature
-Translocation-fragile site
-Deletion and insertion at fragile site

Question 12

What are four types of chromosomal structure abnormalities?

Answer 12

-deletion
-Duplication
-Inversion
-Translocation

Question 13

Rare form of cancer that rapidly develops from the immature cells of a retina, the light-detecting tissue of the eye. It is the most common malignant cancer of the eye in children.

Answer 13

Retinoblastoma - d13q14

Question 14

• ber-22/abl-9 fusion gene/protein
• abl carries a domain that can add phosphate groups to tyrosine residues (a tyrosine kinase), the ber-ab/ fusion gene product is also a tyrosine kinase. It turns on cell division in WBC constantly

Answer 14

Chronic Myelogenous Leukemia (CML)
- Philadelphia Chromosome- t(9:22)(q34;q11.2)

Question 15

Types of mutations in the DNA structure?

Answer 15

-Point mutation (base substitutions, silent mutation, missense mutation, nonsense mutation)
-frameshift mutation amino acid sequence change
-deletion
-Insertion
-SNP (when leads to risk factor and or risk marker in disease)

Question 16

What are the possible effects of missense point mutations?

Answer 16

-No change in enzyme activity
-the amino acid is not part of the active site
-The amino acid located at or near the active site
-reduced or absence of enzyme activity

Question 17

Sickle cell disease is an example of what type of mutation?

Answer 17

Missense point mutation

Question 18

What is an example of nonsense point mutation?

Answer 18

Alpha thalassemia

Question 19

ANEUPLOIDY
VERSUS
POLYPLOIDY?

Answer 19

Aneuploidy is the presence of an abnormal number of chromosomes

Polyploidy is the presence of more than two homologous chromosome SETS

Question 20

Example of missense point mutation

Answer 20

Sickle cell anemia

Question 21

Example of nonsense point mutation

Answer 21

Alpha thalassemia

Question 22

Induce from within the cell. Through evolution to conform to the changing environment to survive.
Inheritable, but not necessarily harmful to the host
Will occur in at least one percent of the population

Answer 22

Polymorphism