V L2: Introduction to the DNA molecule

Question 1

what are the two types of nucleic acids?

Answer 1

DNA

RNA

Question 2

what is a nucleolus ?

Answer 2

Ribosome-producing factory

Question 3

what’s a eukaryotic cell?

Answer 3

Eukaryote, any cell or organism that possesses a clearly defined nucleus.

Question 4

repeating pentose-phosphate units….

Answer 4

5’ (arrow) 3’

Question 5

who stated the Double helical structure ?

Answer 5

Watson and Crick 1953

Question 6

DNA strands are….

Answer 6

Anti-parallel strands

Question 7

what are the 5 bases?

Answer 7

adenine 
thymine
guanine
cytosine 
uracil

Question 8

what happens if you heat DNA?

Answer 8

Heating de-stabilises the H-bonds (denaturing)

Question 9

whats temperature required to denature DNA known as?

Answer 9

Tm - melting temperature

Question 10

whats melting temperature of DNA dependent on?

Answer 10

GC% of the sequence

Question 11

what can you do if you have the DNA sequence of one strand?

Answer 11

complementary sequence can be determined

Question 12

what is a autosome and how many do we have?

Answer 12

any chromosome that is not a sex chromosome, 22 pairs.

Question 13

How many pairs fo sex chromosomes do we have?

Answer 13

1

Question 14

males are?

Answer 14

heterogametic

Question 15

what is Multiple mitochondrial genomes (mtDNA) ?

Answer 15

these DO NOT follow Mendelian genetic rules

Question 16

what are cells with a full set of chromosomes known as?

Answer 16

diploid cells

Question 17

what are cells with a half set of chromosomes known as?

Answer 17

haploid cells

Question 18

which sex chromosome is larger?

Answer 18

X is larger then Y

Question 19

How do X and Y chromosomes pair?

Answer 19

at meiosis via psuedoautosomal regions (PAR) at tips of the arms

Question 20

what are a Complex of proteins and DNA that are stacked together known as?

Answer 20

chromatin

Question 21

what size is chromatin?

Answer 21

30 nm fibre condensed form

Question 22

when nuclear DNA is damaged, mitochondrial DNA is often?

Answer 22

preserved

Question 23

mitochondrial DNA is what type of iheritence?

Answer 23

maternal

Question 24

what are the 4 molecular processes ?

Answer 24

1. Transcription
2. RNA processing
3. Translation
4. Replication

Question 25

what is the cell cycle?

Answer 25

mitosis 
cytokinesis 
G1 phase
S phase ( DNA replication)
G2 phase

Question 26

what are the steps of mitosis?

Answer 26

prophase
metaphase
anaphase
telophase

Question 27

what happens in prophase?

Answer 27

Chromatin begins to condense and is visible in the form of chromosomes. Spindle fibres begin to form as well as centrioles.

Question 28

what happens in metaphase?

Answer 28

Chromosomes line up on mitotic spindle. Chromosomes are attached to spindle forms on opposite sides

Question 29

what happens in anaphase?

Answer 29

sister chromatids separate from each other and are pulled towards opposite ends of the cell.

Question 30

what happens in telophase?

Answer 30

mitotic spindle is broken down
Two new nuclei form, one for each set of chromosomes. Nuclear membranes and nucleoli reappear.
The chromosomes begin to decondense

Question 31

what are the two steps of protein synthesis?

Answer 31

1. transcription (DNA copied to RNA)

2. followed by translation (RNA template for the synthesis of a protein)

Question 32

what is meiosis ?

Answer 32

A specialised nuclear division producing haploid cells, reducing the chromosome number by half

Question 33

The information contained in the ____ in the ___ is transcribed into _____ and the _____ contained in the mRNA are translated into an _____ ____ _____.

Answer 33

1. genes
2. DNA
3. mRNA
4. codons
5. amino acid sequence

Question 34

what can a change in gene do?

Answer 34

change ether function of a protein

Question 35

why are proteins useful in forensics?

Answer 35

Proteins can be studied to identify differences in individuals

Question 36

why is RNA useful forensics?

Answer 36

Cells from different biological sources can be identified using RNA