B1.2 Flashcards
1
Q
What is a chromosome?
A
Chromosome:
- Long molecule of DNA
- 46 chromosomes in one cell
2
Q
What is DNA?
A
DNA:
- Deoxyribonucleic acid
- Polymer of repeating units (nucleotides)
- Double helix
3
Q
What are the 4 bases?
A
4 bases:
- Adenine
- Thymine
- Cytosine
- Guanine
4
Q
What is a nucleotide made of?
A
Nucleotide:
- Phosphate
- Ribose sugar
- Nitrogenous base
5
Q
What happens in transcription
A
Transcription:
- Chromosome is unzipped
- Leaving two strands exposed
- One strand is used as a template
- Cytosine binds with guanine
- Uracil binds with adenine (no thymine in transcription)
- Adenine binds with thymine
- DNA zips back
6
Q
What happens in translation?
A
Translation:
- mRNA threads though the ribosome
- Ribosome reads mRNA in groups of 3 (codon)
- Carrier molecules ferry the correct amino acids to the ribosomes
- Links are made between the amino acids
- Carrier molecules leave
7
Q
What are enzymes?
A
Enzymes:
- Biological catalysts
- Speeds up reactions without being used up itself
8
Q
What is an substrate molecule in an enzyme active sight called?
A
Enzyme substrate active sight:
- Enzyme substrate complex
9
Q
What are enzymes used for?
A
Enzymes:
- Used to break down larger molecules into smaller ones
- Used to build large molecules from smaller ones
10
Q
How does substrate concentration increase rate of reaction?
A
Substrate concentration:
- Increasing substrate concentration means more enzyme active sights are occupied
- Once all enzyme active sights are occupied, rate of reaction stays the same as enzymes are all occupied
11
Q
How does temperature increase rate of reaction?
A
Temperature:
- Higher temperature means enzyme and substrate have more kinetic energy to collide
- After optimum is reached, if temperature increases further, enzymes denature
