tips and tricks 1

Question 1

nucleotide is formed of organic part which is … and inorganic part which is…

Answer 1

organic: pentose sugar and nitrogen base

inorganic: phosphate

Question 2

what substances does the bacteriophage use from bacteria during its production?

Answer 2

amino acids in building protein coat and nucleotides in building DNA and RNA

Question 3

just want u 2 know is that

Answer 3

( A + G ) = ( T + C )

Question 4

what enzyme works in red blood cells before they mature during the break down of the nucleus

Answer 4

deoxyribonuclease enzyme

Question 5

What is the enzyme that does not work in a specific direction?

Answer 5

helicase

Question 6

what is the thing that consists of two types of polymers each of them contains H bonds

Answer 6

nucleosomes
the 2 polymers are DNA and histones

Question 7

the viral DNA replicates inside…

Answer 7

the host cell عموما
مش بيعتمد اماكن معينة

Question 8

what is penicilium?

Answer 8

a desirable induced mutation that increase the amount of antibiotics (polyploidy
) increase in the number of chromosomes
chromosomal mutation1

Question 9

between 2 adjacent nucleotides

Answer 9

a covalent bond

Question 10

between 2 complementary nucleotides

Answer 10

Hydrogen bond

Question 11

why is it made of hydrogen bond?
or
why is hydrogen bond weak?

Answer 11

to be easily broken during protein synthesis and replication

Question 12

each turn is the double helix

Answer 12

20 nucleotides

Question 13

each turn in the single strand

Answer 13

10 nucleotides

Question 14

the half thickness of DNA molecule

Answer 14

1 nm

Question 15

complete thickness of DNA is

Answer 15

2 nm

Question 16

the distance between 2 successive sugar molecules on the same DNA strand

Answer 16

0.34 nm

Question 17

the length of 3 turns

Answer 17

3 times 3.4 = 10.2

Question 18

how many DNA in a sperm

Answer 18

2 types of DNA
circular in mitochondria (midpiece)
linear in nucleus (head)

Question 19

which phase is the crossing over?

Answer 19

meiosis 1

Question 20

structural unit of chromosome

Answer 20

nucleosome

Question 21

structural unit of DNA

Answer 21

nucleotides

Question 22

structural unit of protein

Answer 22

amino acids

Question 23

proteins responsible for the functional performance of DNA molecule

Answer 23

regulatory non histones
بينظم

Question 24

moving a nucleotides in the chromosome
the type of mutation is…

Answer 24

gene mutaion

Question 25

proteins responsible for the spatial organization

Answer 25

structural non histones

Question 26

proteins responsible for making DNA fit into the nucleus used in packing

Answer 26

structural non histones and histones

Question 27

when a bacteriophage inserts its DNA into the bacterial cell it can still survive if:

Answer 27

the bacterial cell contains restriction endonuclease enzyme which breaks the viral DNA

Question 28

okazaki fragments ?

Answer 28

gaps between the sugar phosphate backbone built from the template 5 to 3 (lagging strand) are joined by ligase by covalent bonds (phosphodiester bond)

Question 29

# sperms from spermatids the following changes are not considered a cell division

Answer 29

* formation of zygospore from zygote in spirogyra algae (zygote is coated by a thick coat so, zygospore is formed) * primary spermatocyte from spermatogonia * primary oocyte from oogonia * sperms from the spermatids * ookinete from zygot of plasmodium malaria

Question 30

if the mutation happened in the mitochondria of the sperm

Answer 30

it will not be inherited to the zygote as the mitochondria in the midpiece of the sperm and does not enter the ovum

Question 31

if the mutation happened in the mitochondria of the ovum

Answer 31

the mutation will be inherited to the zygote

Question 32

if the mutation occurs to chromosome Y in the sperm

Answer 32

mutation will be transferred to the produced male YX not females XX

Question 33

normal size of f fruit and no seeds

Answer 33

parthenocarpy

Question 34

what is the number of the free OH group in somatic cell

Answer 34

2N so 46 DNA molecules 46 times 2 = 92

Question 35

E coli are...

Answer 35

prokaryotic

Question 36

gene mutation can happen in

Answer 36

reproductive cells and somatic cells

Question 37

what is the common thing between all mutations?

Answer 37

**A sudden change**

Question 38

helicase and ligase are

Answer 38

**rrgulatory proteins** made up of amino acids