Unit 6 Flashcards
(47 cards)
What are the bases of RNA
A U C G
What are the bases of DNA
A T C G
How many Kj of energy are stored in ATP
30.6kJ
Why is ATP called a universal energy currency
It is used to provide energy for all reactions in all living organisms
Describe 3 ways ATP can be used for
- Releases energy in small usable amounts
- Travels easily to where it may be used for secretion, muscle contraction and active transport
- Only 1 enzyme is needed to release energy from ATP
What is the structure of RNA
Single stranded polynucleotide
Contains Pentose ribose
What is the role of messenger RNA
carries the genetic code from the DNA to the ribosomes in the cytoplasm
Where is mRNA synthesised in
in the nucleus
Where is rRNA found in
Cytoplasm
What is rRNA made from
Ribosomal RNA and protein
What is rRNA the site of
Translation and the genetic code of protein
What does tRNA do
Folds
Why does tRNA fold
So that in places there are base sequences forming complimentary pairs
What is the shape of tRNA described to look like
A cloveleaf
The 3’ end of tRNA what base sequences are located
Cytosine-cytosine-adenine
Are tRNA and rRNA long or short?
Short
What are the 2 main roles of DNA
Replication
Protein synthesis
What is the process of DNA replication
1.Enzyme DNA helicase attaches onto DNA molecule causing the hydrogen bonds to break between the complimentary bases separating the polynucleotides
2. Free nucleotides line up with their complimentary bases and are held in place by hydrogen bonds
3. RNA polymerase attaches onto DNA nucleotide and moves down the molecule forming a phosphodiester bond between the activated nucleotide, condensation reaction happens
4. When the phosphodiester bond is formed, the activated nucleotides lose 2 phosphate groups providing energy
What is the process of transcription
- DNA helicase unzips a section of DNA and breaks hydrogen bond between the complimentary base pairs
- RNA polymerase links to the template coding strand of DNA and attaches mRNA nucleotides to there complimentary base pairs
- This copying stops at stop codon
- The newly made premRNA leaves the DNA
- Post transcription a modifications happens to remove non coding introns
- Mature mRNA leaves nucleus into cytoplasm for translation
What is the process of translation
- Small subunit of ribosomes bind to mRNA at the start codon
- A tRNA molecule with the anticodon complimentary attaches to the start codon held by hydrogen bonds
- 2nd tRNA molecule moves into place and peptide bond is formed between 2 amino acids
- 1st tRNA molecule is released and keeps moving along polypeptide until stop codon is reached
What is the process of inspiration
- Intercostal muscles contract lifting ribs up and out
- Diaphragm contracts and flatterns
- Chest cavity increases in volume and decreases in pressure outside the body, so air is sucked n to equalise the pressure
What is the process if expiration
- Intercostal muscles relax and ribs are moved down and in
- Diaphragm relaxes and comes up
- Chest cavity decreases in volume and increases in pressure, air is forced out
What are 4 ways the alveoli are adapted for gas exchange by
- Good blood supply
- Large surface area
- Thin walls
- Moist lining
What does peak flow measure
Lung function
How fast you can breathe in and out
