Practice Flashcards
Flip to reveal answersTrack your progress — Sign up free to save your progress and get smart review reminders based on spaced repetition.
All 7 Flashcards — Gene expression and why cells differ
Sign up free to track progress and get spaced-repetition review schedules.
Question
Define gene expression.
Answer
The **transcription and translation** of a gene to make its **protein** (the gene's product).
Question
What is a gene's 'product'?
Answer
The **protein** that the gene codes for — the end result of expressing it.
Question
Every cell in your body has the same DNA. So why are cells different?
Answer
**Differential gene expression** — each cell type switches on a **different subset** of genes, so it makes different proteins.
Question
What happens to a gene's protein if the gene is switched off?
Answer
The gene is **not transcribed**, so **no mRNA and no protein** are made — even though the gene is still in the DNA.
Question
Define differential gene expression.
Answer
Different cell types expressing **different subsets** of the same genome, so each makes a different set of proteins.
Question
What is cell differentiation, in terms of genes?
Answer
A cell settling into a **stable pattern** of which genes it expresses — a 'cell type' is just a particular set of switched-on genes.
Question
A neuron and a red blood cell both have the haemoglobin gene. Why does only one make haemoglobin?
Answer
The red-blood-cell precursor **expresses** (switches on) the gene; the neuron keeps it **off**, so only the red blood cell makes the protein.
Read the notes
Full study notes for Gene expression and why cells differ
Topic 4.5 hub
Gene expression
More from Topic 4.5
All flashcards in this topic
Biology exam skills
Paper structures & tips
Track your progress with spaced repetition
Sign up free — Aimnova tells you exactly which cards to review and when, so you remember everything before your IB exam.
Start Free