THE CHEMICAL BASIS OF HEREDITY(lesson 2)geenetics hindi pa done

Question 1

hereditary transmission and
variation on the molecular level.

Answer 1

Molecular Genetics

Question 2

The study of the molecular
structure of genes, involving

Answer 2

DNA and RNA.

Question 3

We now accepted that
there was genetic transmission of
traits.

Answer 3

From Mendel:

Question 4

The genetic material must contain the information necessary to construct an
entire organism.

Answer 4

INFORMATION

Question 5

During reproduction, the genetic material must be passed from parents to
offspring.

Answer 5

TRANSMISSION

Question 6

Because the genetic material is passed from parents to offspring, and from
mother cell to daughter cells during cell division, it must be copied.

Answer 6

REPLICATION

Question 7

species, a significant amount of phenotypic variability occurs. The
genetic material must also vary in ways that can account for the known
phenotypic differences within each species.

Answer 7

VARIATION

Question 8

Conducted experiments that involved the
injection of live and/or heat-killed
bacteria into mice.

Answer 8

Frederick Griffith (1928)

Question 9

He then observed whether or not the
bacteria caused a lethal infection.

Answer 9

Frederick Griffith (1928)

Question 10

Discovered that a “transforming factor”
changes harmless bacteria into a
deadly one.

Answer 10

Frederick Griffith (1928)

Question 11

experiments showed that some
genetic material from the dead bacteria had
been transferred to the living bacteria and
provided them with a new trait.

Answer 11

Frederick Griffith (1928)

Question 12

Realized that Griffith’s
observations could be used as
part of an experimental strategy
to identify the genetic material.

Answer 12

Oswald Avery, Colin MacLeod,
and Maclyn McCarty (1944)

Question 13

only one of the extracts, namely, the one
that contained purified DNA from type S bacteria, was able to
convert type R bacteria into type S.

Answer 13

Oswald Avery, Colin MacLeod,
and Maclyn McCarty (1944)

Question 14

They used radioisotopes to
distinguish proteins from DNA.

Answer 14

Alfred Hershey and Martha Chase
(1952)

Question 15

Performed the definitive
experiment that showed that DNA
was the genetic

Answer 15

Alfred Hershey and Martha Chase
(1952)

Question 16

This virus infects Escherichia coli bacterial cells
and is therefore known as a ___, or simply a
phage.

Answer 16

t2, bacteriophage

Question 17

two types of macromolecules:

Answer 17

DNA
and proteins.

Question 18

MOST ABUNDNAT FREE NUCLEOTIDE IN MAMMALIAN CELL

Answer 18

ATP-

Question 19

BUILDING BLOCKS OF NUCLEIC ACIDS

Answer 19

NUCLEOTIDE

Question 20

Refers to nitrogen-containing heterocyclic ring structures

Answer 20

Nitrogenous Base

Question 21

2 types of Nitrogenous Base

Answer 21

PURINE PYRIMIDINE
Adenine Cytosine
Guanine Uracil
Thymine

Question 22

STRUCTURE OF A PURINE RING

Answer 22

• 5 Carbons
  2 from Glycine
  2 from N10- Formyl-
  tetrahydrofolate
  1 from CO2
• 4 Nitrogen
  1 from Glycine
  2 from Glutamine
  1 from Aspartate

Question 23

NUCLEOTIDE =

Answer 23

(Nitrogenous base + Pentose sugar) +
Phosphate

Question 24

NUCLEOSIDE =

Answer 24

Nitrogenous base + Pentose sugar

Question 25

serves as the bond between the base and sugar (nucleosides are N-glycosides)

Answer 25

N-glycosidic linkage:

Question 26

Refers to the combination of nitrogenous base & pentose sugar

Answer 26

NUCLEOSIDE

Question 27

Refers to the combination of nucleoside + phosphate

Answer 27

NUCLEOTIDE

Question 28

serves as the bond between the 5’-OH of pentose sugar and phosphoryl group

Answer 28

Ester bond

Question 29

Pentose Sugar * 2 types:

Answer 29

DNA RNA 2’-deoxy D-Ribose (Deoxyribose) D-Ribose (Ribose)

Question 30

are polymers of nucleotides joined by a 3’-5’ phosphodiester bond

Answer 30

Nucleic acids

Question 31

, are known as nucleic acids.

Answer 31

DNA and RNA

Question 32

This term is derived from the discovery of DNA by __ in 1869.

Answer 32

Friedrich Miescher

Question 33

He identified a novel phosphorus- containing substance that was isolated from the nuclei of white blood cells found in waste surgical bandages. He named this substance___.

Answer 33

Friedrich Miescher, nuclein

Question 34

Mostly seen in NUCLEUS Pyrimidine bases: THYMINE, CYTOSINE Sugar: DEOXYRIBOSE Usually DOUBLE-STRANDED

Answer 34

DNA

Question 35

Mostly seen in CYTOPLASM Pyrimidine bases: URACIL, CYTOSINE Sugar: RIBOSE SINGLE-STRANDED

Answer 35

RNA

Question 36

A phosphate group connects two sugar molecules via

Answer 36

ester bonds

Question 37

For this reason, the linkage in DNA (or RNA) strands is called a

Answer 37

phosphodiester linkage.

Question 38

form the backbone of the strand.

Answer 38

phosphates and sugar molecules

Question 39

Three scientists who worked together on studying the structure of DNA

Answer 39

James Watson, Francis Crick, Rosalind Franklin

Question 39

The ___ is negatively charged due to a negative charge on each phosphate.

Answer 39

backbone

Question 40

The proposed model was based on the X-ray diffraction photographs of DNA taken

Answer 40

Rosalind Franklin

Question 41

won a Nobel Prize in 1962 for their discovery

Answer 41

Watson and Crick

Question 42

She adjusted her equipment to produce an extremely fine beam of X- rays. She extracted finer DNA fibers than ever before and arranged them in parallel bundles.

Answer 42

Rosalind Franklin

Question 43

Right-handed (clockwise) double-stranded DNA helix

Answer 43

COMPOSITION

Question 44

is STRONGER than A-T bonding

Answer 44

G-C bonding

Question 45

g-c bonding a-t bonding

Answer 45

3 hydrogen bonds 2 hydrogen bonds

Question 46

major groove, minor groove

Answer 46

G-C bonding

Question 47

often acts as sites of DNA-protein interaction

Answer 47

Grooves

Question 48

(Erwin Chargaff’s rule):

Answer 48

%G = %C %A = %T

Question 49

is via hydrophobic interaction & ionic bonding

Answer 49

DNA-protein interaction

Question 50

* discovered the % content of the 4 nucleotides was the same in all tissues of the same species

Answer 50

ERWIN CHARGAFF

Question 51

States that the number of purines = number of pyrimidines

Answer 51

CHARGAFF’S RULE

Question 52

All types of DNA are right- handed,

Answer 52

except Z

Question 53

6 types have been identified – A, B, C, D, E and Z, but the 3 more prominent types are

Answer 53

A, B, and Z

Question 54

* Most abundant chromatin protein

Answer 54

HISTONES

Question 55

divided into 2 types:

Answer 55

core histones, linker histones

Question 56

LEVELS OF DNA ORGANIZATION

Answer 56

*DNA double helix *10 nm chromatin fibril *30 nm chromatin fibril *Supercoiled structure *Chromosome

Question 57

shorter than chromosomal DNA,

Answer 57

RNA STRUCTURE

Question 58

Different arrangements of base pairing are possible, which result in structures called

Answer 58

bulge loops, internal loops, multibranched junctions, and stem-loops (also called hairpins).