Biology

Created by: jatyization
Created on: 30-04-15 17:33

How does oestrogen effect gene transcription in a target cell?

Oestrogen binds to complimentary receptor molecule on the transcriptional factor; This changes shape and causes inhibitor to be released; Transcriptional factor then binds to DNA promoter; Stimulates transcription of DNA

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Explain why the percentage of bases from the middle par to the chromosome and the end part are different.

Different genes; Different base sequence; Pre-mRNA transcribed from different DNA

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Suggest how they can use electrophoresis to estimate the number of base pairs in the separated fragments.

Smaller fragments move further and faster; Compare distance moved by fragments of known size; DNA ladder

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Plants grown for seeds have highly variable yields, explain why.

Meiosis; Independent assortment; Random fusion of genetically different gametes

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What is the degenerate code?

Amino acids have more than one codon

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What is meant by stop codons?

Codons which do not code for any amino acid and mark the end of a polypeptide chain

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What is meant by universal code?

Same codons for the same amino acid in all organisms

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What are the roles of proto-oncogenes?

Receptor protein on the cell-surface membrane can be permanently activated; Cell division switched on in absence of growth factors; Oncogene may code for growth factor that is produced in excessive amounts = cancer develops due to rapid cell division

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What are the roles of tumour suppressor genes?

Inhibit cell devision

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Other cards in this set

Card 2

Front

Explain why the percentage of bases from the middle par to the chromosome and the end part are different.

Back

Different genes; Different base sequence; Pre-mRNA transcribed from different DNA

Card 3

Front

Suggest how they can use electrophoresis to estimate the number of base pairs in the separated fragments.

Back

Card 4

Front

Plants grown for seeds have highly variable yields, explain why.

Back

Card 5

Front

What is the degenerate code?

Back

View more cards

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Biology