DNA and RNA Flashcards
What are two ways of identifying different amino acids?
- Two chromotography:
Turning the paper 90 degrees and retesting to obtain a more accurate Rf value - Electrophesis:
Placing the solution in a circuit, it separates based on charge
Chromosome
23 pairs
structure where genes are stored
chromatin
genetic material not during mitosis
Histones
proteins that keep the DNA organised
Uses of mitosis
- Growth in the number of cells present
- Replace dead or non-functioning cells
A sexual reproduction
binary fission
plants eg strawberry
Pros and cons of a-sexual reproduction
Pros
- only requires one organism
- can survive as a species more easily
Cons
- no variation, genetically identical, therefore change in environment could kill the whole species
What is mitosis?
cell division producing two genetically identical
Why is the genetic code described as being universal
The same bases are used across organisms and each codon codes for the same amino acids
What are the two stages of protein synthesis
Transcription and translation
Mitotic index
number of cells in mitosis / Total number of cellls
How do you take a representative sample of mitotic index
view different areas of tissue and then calculate a mean
What does having a high mitotic index mean
- over 0.5
- Either it is actively growing
- Or it is a cancer, excessive growing
Interphase
Cell is actively synthesising proteins. Chromosomes are invisible and DNA replication occurs
Prophase
Chromosomes condense and become visible. nuclear envelope disintegrates
Metaphase
Spindle forms and line up at the equator
Anaphase
Spindle fibres contract and chromatids are pulled towards the poles
Telophase
Chromatids reach poles, unravel and the nuclear envelope forms
