L29

Question 1

WHAT is the 3 type of genetic disease?

Answer 1

1-monogenic disease
2-polygenic disease
3-chromosomal disease

Question 2

monogenic disease happen due to ?

Answer 2

it happen due to mutation occurring in the gene [ one gene] that encode for a protein

Question 3

polygenic disease happen due to ?

Answer 3

due to mutation in multiple gene and their interaction with environmental factors

Question 4

example of monogenic disease ?

Answer 4

Sickle-cell anemia [ single gene disorder ]

Question 5

example of polygenic disease ?

Answer 5

Type 2 diabetes

Question 6

what cause human syndromes?

Answer 6

human syndromes are caused by chromosomes abnormalities [ numerical abnormality or structual abnormalities ]

Question 7

what is the 2 type of numerical abnormality ?

Answer 7

1- aneuploidy

2-polyploidy

Question 8

what is aneuploidy ?

Answer 8

gain [ trisomy 47] or loss [ monosomy 45 ] of chr in a cell and it can occur in both sex chr and autosomes

Question 9

Ex of disease happen in sex chr ?

Answer 9

turner syndrome in girls [ monosomy 45 chr]

klinefetter syndrome in boys [ trisomy 47 chr]

Question 10

monosomy [ turner ] and trisomy [ klinefetter ] occur as a result of an error in ?

Answer 10

error in meiosis cell division through Nondisjunction

Question 11

what is nondisjunction ?

Answer 11

it failure for homogenies chr to separate properly during mieosis

Question 12

true or false

nondisjunction can occur in meiosis 1 or mitosis?

Answer 12

false !

it can occur in meiosis 1 or meiosis 2

Question 13

Autosomes can occur through ?

Answer 13

non disjunction in meiosis or mitosis [alternations in autosomes ]

Question 14

what is the 3 type of trisomies that result in baby that can survive for a time after birth ?

Answer 14

[13,18,21]
اذا كان عندنا طفل مثلا عنده تضاعف بالكروموسوم 4 على
😢 طول للاسف يموت

Question 15

what is trisomy 21 [ down syndrome] symptoms ?

Answer 15

significantly reduced IQ

chracteristic features

Question 16

what happen during mieosis in trisomy21 [ down syndrome]?

Answer 16

nondisjunction during meiosis 1 [homologous chromosomes pair fail to separate and go to the same doughter cell

nondisjunction during meiosis 2 [ sister chromatids fail to separate and will go to the same gamete

Question 17

what happen during mitosis in trisomy 21[ down syndrome]?

Answer 17

non disjunction of ch 21 causing one cell to have 47 chr and the other have 45 chr

Question 18

trisomy 18 cause ?

Answer 18

edwards syndrome, which is a severe disorder of heart and kidneys and if the fetus survive to birth the median lifespan is 5 to 15 days

Question 19

trisomy 13 cause ?

Answer 19

patau syndrome ,which is sever birth defect including heart and kidney disorder as well as malformation
80% newbabys do not survive long then one year

Question 20

what is sex chr syndrome and autosomes chr syndrome ?

Answer 20

sex chr [ happen in meiosis
Monosomy [ turner syndrome ]
trisomy [ klinefetter syndrome ]

Autosomes chr [ happen in meiosis and mitosis]
trisomy 21 [ down syndrome ]
trisomy 18 [ eduard syndrome ]
trisomy 13 [ patau syndrome]

Question 21

true or false

true polyploidy commanly occurring in human although it occurs in some tissues [ especially in the liver ]

Answer 21

false

it rerly occurring in human

Question 22

diploid male gameteis ferilized by normal haploid female gamates give us ?

Answer 22

triaploid 3n=69 [ baby miscarry or die within the first year of life

Question 23

male gameteis ferilized by diploid female gamates give us ?

Answer 23

tetraploid 4n=92 [ baby usually dies in uterus

Question 24

when does structural chr happen?

Answer 24

Structural abnormalities occur whena part of a chromosome is abnormal. Examples:
Deletion
Duplication Insertion Inversion
Translocation

Question 25

what is delation ?

give me an Ex

Answer 25

A portion of the chromosome is missing or deleted. Best example is Cri du chat syndrome
nm
• Cri du chat syndrome:
• Deletion at the end of short arm of chromosome 5,
focus chr 5 555555555

Question 26

what is duplication ?

Answer 26

a portion of the chr is duplicated resulting in extra genetic material
protein 22
chr 17

Question 27

what is insertion ?

Answer 27

portion of one chromosome has been deleted from its normal place and inserted into another chromosome.

Question 28

what is inversion?

Answer 28

An inversion is a chromosome rearrangement in which a segment of a chromosome is reversed end to end.

• An inversion occurs when a single chromosome undergoes breakage and rearrangement within itself.

• Inversions are of two types:
• Paracentric
• Pericentric =within centromere

Question 29

what is translocation ?

Answer 29

Reciprocal Translocation is the exchange of chromosome segments between two non-
homologous chromosomes.
Translocation occurring between chromosomes 14 and 21[ down syndrome]