Biology PT1

Question 1

Transcription

Answer 1

• DNA unwinds and RNA Polymerase attaches to the promoter region.
• DNA template strand is copied into pre-mRNA via complementary base pairing using RNA polymerase.
• pre-mRNA undergoes RNA processing. Introns are removed, a 5’ methyl cap and 3’ poly-A tail are added to form mRNA.
• mRNA leaves the nucleus and goes to a ribosome.

Question 2

DNA in prokaryote

Answer 2

single circular chromosome

Question 3

DNA in eukaryote

Answer 3

linear chromosome

Question 4

Nucleic acids

Answer 4

• made up of C.H.O.N.P
• eg. DNA & RNA
• made up of nucleotides (monomers of NA)

Question 5

ATP

Answer 5

(Adenosine triphosphate)

ATP is the molecule of energy in cells

Question 6

Nitrogenous bases

Answer 6

car in garage = Cytosine + Guanine

apple tree = Adenine + Thymine/(Uracil in RNA)

Question 7

Pyrimidines

Answer 7

CUTe (smaller)
C= cytosine
U= uracil
T= thymine

Question 8

Purines

Answer 8

Pure Ag (larger)
A=adenine
G=guanine

Question 9

How many bonds b/w A and T

Answer 9

A-T = (T)wo

Question 10

How many bonds b/w C and G

Answer 10

C-G = thr(EE)

Question 11

Genome

Answer 11

all of the DNA in an organism or cell

Question 12

mRNA (name + function)

Answer 12

messenger RNA = transfers genetic code from nucleus to the ribosome

Question 13

rRNA (name + function)

Answer 13

ribosomal RNA = the structural component of ribosomes aswell as proteins

Question 14

tRNA (name + function)

Answer 14

transfer RNA = brings the correct and specific amino acids to the ribosome

Question 15

What are the three types of RNA

Answer 15

• messenger RNA (mRNA)
• transfer RNA (tRNA)
• ribosomal RNA (rRNA)

Question 16

DNA vs RNA …..(3 differences)

Answer 16

DNA: RNA:
contains thymine contains uracil
contains deoxyribose contains ribose
double-stranded single-stranded

Question 17

monomer of protein

Answer 17

amino acids

Question 18

proteome

Answer 18

entire set of proteins expressed by an organism at a given time

Question 19

Proteins

Answer 19

• made up of C.H.O.N and occasionally S
• eg. actin and myosin
• made up of amino acids (monomer of P)

Question 20

Draw and label an amino acid

Answer 20

H\ |R //O
N - C - C
H/ |H \OH

Question 21

what bond is formed when 2 amino acids are joined

Answer 21

peptide bond

Question 22

process of joining amino acids

Answer 22

condensation polymerisation

Question 23

Primary structure of a protein

Answer 23

sequence of amino acids, joined by peptide bonds

Question 24

primary structure bond/s

Answer 24

peptide bonds

Question 25

Secondary structure of a protein

Answer 25

the folding of the primary structure into alpha helix, beta-pleated sheets or randomly folded.

Question 26

secondary structure bond/s

Answer 26

Hydrogen bonds Ionic bond Disulphide bridges

Question 27

Tertiary structure of a protein

Answer 27

A 3D structure composed of a folded secondary structure

Question 28

tertiary structure bond/s

Answer 28

Hydrogen bonds Ionic bonds Disulphide bridges

Question 29

Quaternary structure of a protein

Answer 29

two or more polypeptide chains joined together

Question 30

Fibrous proteins

Answer 30

STRUCTURAL collagen - strength/ in skin, tendons + bones elastin - stretch/arteries to vaso/c/d in ^ pressure

Question 31

Globular proteins

Answer 31

FUNCTIONAL enzymes - specific + compl. active site to bind w sub hormones

Question 32

functions of proteins

Answer 32

P-protection...antibodies M-movement...actin/myosin ``` C-cell recognition...antigens/receptors H-hormones...insulin E-enzymes...amylase S-structure...collagen/elastin/keratin T-transport...haemoglobin/protein channel ```

Question 33

nucleus

Answer 33

DNA transcribed into mRNA during transcription

Question 34

ribosome

Answer 34

translates mRNA code into a polypeptide

Question 35

rough endoplasmic reticulum

Answer 35

folding and transport of polypeptide into transport vesicles

Question 36

golgi apparatus

Answer 36

final modification and packaging of proteins into secretory vesicles

Question 37

secretory vesicles

Answer 37

allow protein to leave the cell via exocytosis

Question 38

Order of the PPP

Answer 38

Nucleus - Ribosome - Rough ER - Transport vesicle - golgi apparatus - secretory vesicle

Question 39

Promoter region

Answer 39

where RNA polymerase attaches

Question 40

operator region

Answer 40

where transcriptional factors attach to either repress or activate transcription

Question 41

Translation

Answer 41

- Ribosomes read the mRNA code. - tRNA brings the correct and specific amino acids to the ribosome. - tRNA anticodons are complementary and specific to mRNA codons. - Amino acids are joined together by a peptide bond, in a condensation polymerisation reaction, and a polypeptide is formed.

Question 42

Start instructions

Answer 42

the point in a gene after the promoter region, where transcription begins

Question 43

Stop instructions

Answer 43

in the form of a transcription terminator, which causes RNA polymerase and transcriptional factors to dissociate, as there mRNA formed from this gene will have no complementary and specific tRNA to attach here

Question 44

Gene regulation

Answer 44

the cellular control of the amount and timing of appearance of the functional product of a gene (proteins.)

Question 45

Regulatory genes

Answer 45

controls another gene, by coding for a transcriptional factor like a repressor protein

Question 46

Structural genes

Answer 46

a gene that codes for a protein that becomes part of the structure or function of an organism. eg. enzyme or protein channel