DNA, The Code of Life

Question 1

nucleic acids

Answer 1

organic molecules that controls the synthesis of proteins in all living cells by storing and transferring genetic information

Question 2

where does DNA occur and what does it form

Answer 2

the nucleus where it forms part of the chromatin network/chromosomes

Question 3

what is extranuclear DNA

Answer 3

DNA that occurs outside the nucleus in small amounts

Question 4

define histones

Answer 4

proteins that DNA is wrapped around

Question 5

define genes

Answer 5

short segments of DNA molecules that codes for a particular protein

Question 6

what is the function of genes

Answer 6

each gene carries the code for synthesis of a particular protein which determines the characteristics of an organism

Question 7

what are the monomers of DNA called

Answer 7

nucleotides

Question 8

what are the three parts of the DNA nucleotides

Answer 8

deoxyribose sugar
phosphate group
nitrogenous base

Question 9

what are the four nitrogenous bases of DNA

Answer 9

adenine
guanine
cytosine
thymine

Question 10

which two nitrogenous bases are known as purine and why

Answer 10

adenine and guanine, because they are large

Question 11

which two nitrogenous bases are known as pyrimidine and why

Answer 11

cytosine and thymine because they’re smaller molecules

Question 12

how many hydrogen bonds does adenine and thymine have

Answer 12

2

Question 13

how many hydrogen bonds do guanine and cytosine have

Answer 13

3

Question 14

how is DNA formed

Answer 14

the deoxyribose sugar of one nucleotide forms a bond with a phosphate of another
the nitrogenous bases are joined by weak hydrogen bonds that are easily broken by enzyme action

Question 15

why is the sequence of nitrogenous bases so important

Answer 15

it provides the code that gives the instructions for the synthesis of proteins.

Question 16

what is the role of DNA

Answer 16

• to carry genetic information

- to replicate and ensure the genetic code is accurately transferred

Question 17

when does DNA replication take place

Answer 17

during interphase

Question 18

process of DNA replication

Answer 18

• double helix structure unwinds
• weak hydrogen bonds break and the two DNA strands unzip
• free-floating nucleotides in the nucleoplasm builds a complementary DNA strand onto the two original DNA strands

Question 19

what is the importance of DNA replication

Answer 19

to ensure each daughter cell contains the same genetic information as the mother cell

Question 20

what is DNA profiling used for

Answer 20

• identifying crime suspects
• proof of paternity
• determining the probability of genetic defects

Question 21

where does RNA occur?

Answer 21

the nucleus and cytoplasm

Question 22

what does RNA form part of

Answer 22

ribosomes

Question 23

what are the 4 nitrogenous bases of RNA

Answer 23

• adenine
• guanine
• cytosine
• URACIL

Question 24

how is RNA formed

Answer 24

when nucleotides join, the ribose of one nucleotide attaches to the phosphate group of another to form a single strand.

Question 25

function of mRNA

Answer 25

to carry the genetic code from DNA in the nucleus to the ribosomes in the cytoplasm

Question 26

function on tRNA

Answer 26

to pick up amino acids in the cytoplasm and take them to the ribosomes where protein synthesis occurs

Question 27

function of rRNA

Answer 27

forms part of the ribosomes in the cytoplasm and plays a role in protein synthesis

Question 28

what is protein synthesis

Answer 28

when proteins are made in living cells

Question 29

where does protein synthesis take place

Answer 29

at the ribosomes in the cytoplasm

Question 30

what controls protein synthesis

Answer 30

DNA and RNA

Question 31

define base triplet and what do they determine

Answer 31

three consecutive nitrogenous bases on the DNA strand

they determine which of the amino acids will link which thus determines what protein is contructed

Question 32

define transcription

Answer 32

where mRNA obtains the code for protein synthesis from DNA

Question 33

define translation

Answer 33

the processing of the code locked in the mRNA strand to form a certain amino acid sequence in the synthesis of a particular protein