Regulation of transcription and translation

Question 1

What are transcriptional factors?

Answer 1

Proteins that control the rate of protein synthesis by switching genes on or off

Question 2

Where are transcriptional factors found and where do they move to?

Answer 2

Found in the cytoplasm and move to the nucleus

Question 3

What type of structure do transcriptional factors have?

Answer 3

Tertiary structures

Question 4

What is the promoter region?

Answer 4

Short sequence of DNA at the start of a gene and it is the part where RNA polymerase attaches to

Question 5

What are the 2 types of transcriptional factors?

Answer 5

Activators - help bind RNA polymerase so gene is transcribed
Repressors - prevents RNA polymerase from binding so gene is not transcribed

Question 6

How does the usage of transcriptional factors allow cell specialisation?

Answer 6

Some genes are turned off or on which results in certain proteins being transcribed which leads to specialisation

Question 7

What is oestrogen?

Answer 7

A steroid hormone which is both lipid soluble and non-polar so can diffuse through the phospholipid bilayer of a cell surface membrane

Question 8

How does oestrogen work and what does it do?

Answer 8

• Oestrogen can initiate transcription by binding to a receptor on a transcriptional factor.
• When this binding happens, it changes the tertiary structure of the binding site, making it complementary to the DNA.
• The transcriptional factor can now bind to the DNA which enables DNA polymerase to bind so the gene can be transcribed.