Chromosomal Abberations

Question 1

sex-linked traits

Answer 1

traits linked to genes on x and y chromosomes

Question 2

sex-influenced traits

Answer 2

expressed in both sexes, but controlled by differing hormone levels in males v. females

Question 3

sex-limited traits

Answer 3

traits expressed in only one sex because of hormonal influence

Question 4

Lyon effect

Answer 4

x cs inactivation

-affects all X chromosomes in excess of one cs per cell during very early embryonic development

Question 5

barr body

Answer 5

-inactive x chromosome in the female cell

Question 6

XIST protein

Answer 6

• gene on x cs produces XIST RNA
• coats excess X cs which leads to inactivation
• some genes on inactive x cs are still active and are able to transcribe
• once they are acted on, the cs’ genes are passed to the next generation of cells within the organism in the same inactive or activated state

Question 7

X- chromosome inactivation

Answer 7

• affects all X cs in excess of one cs per cell during very early embryonic development
• forms barr bodies depending on the number of x chromosomes

Question 8

mosaic

Answer 8

-some heterozygous states may cause non-uniform phenotypes
-ex calico cat, weird sweat glands
-

Question 9

nondisjunction

Answer 9

• changes in cs number
• error in which cs failed to properly separate in mitosis or meiosis I or II
• mitosis can result in organisms mosaic phenotype
• error in gamete(egg or sperm) which causes entire orgamism to be errored and which can be related to teh mothers age or environmental influence

Question 10

monosomy

Answer 10

lack of one chromosome which is lethal so spontaneosuly abortion

Question 11

trisomy

Answer 11

-addition of a cs
-most are lethal which results in spontaneous abortion or they die shortly after birth
1. Trisomy 13/18 are multi system errors which make extra proteins
they could birth but they die
2. Trisomy 21 is downs syndrome which is viability

Question 12

sex chromosome errors

Answer 12

• result in error of entire organism

- generally viable

Question 13

Klinefelter syndrome

Answer 13

• sex cs error
• 47 XXY
• male breast tissue develops
• tested not fully developed
• lower IQ

Question 14

Turner syndrome

Answer 14

• sex cs error
• 45, XO
• female, shorter, undiffernetiated gonads, ovarian streaks do not turn into the ovary
• stay prepubescent bc ovary does not make progesterin or estrogen

Question 15

Jacob Syndrome

Answer 15

• sex cs errror
• 47 XYY
• tall, lower IQ, not really noticable

Question 16

poly X(meta female syndrome)

Answer 16

• sex error cs
• 47 XXX
• tripolid
• spaitial relationship problems
• not noticable

Question 17

polyploid

Answer 17

-any abnormal multiple of N
-generally will spontaneously abort if birthed, will die shortly after birth
ex 46 dipolid
69 triploid
92 tetraploid