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Flip to reveal answersWhat is a 'typical' cell?
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All 12 Flashcards — Atypical cell structure
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Question
What is a 'typical' cell?
Answer
A cell that fits the standard description: **one nucleus**, **microscopic** size, and its **own sealed membrane** (and wall in plants/fungi).
Question
What does 'atypical cell' mean?
Answer
A cell that **does not fit the typical description** — e.g. it lacks a nucleus, has many nuclei, is unusually large, or shares its cytoplasm.
Question
What does 'anucleate' mean?
Answer
Having **no nucleus**. ('a-' = without.)
Question
What does 'multinucleate' mean?
Answer
Having **many nuclei** inside one cell or fibre. ('multi-' = many.)
Question
What does 'aseptate' mean?
Answer
Having **no cross-walls (septa)**, so the cytoplasm is **continuous** — seen in some fungal hyphae.
Question
Name two anucleate (atypical) cells.
Answer
A **mature mammalian red blood cell** and a **phloem sieve tube element** — both lose their nucleus.
Question
Which atypical cell is multinucleate, and why?
Answer
A **skeletal (striated) muscle fibre** — many cells **fuse** into one long fibre with many nuclei.
Question
Why does a red blood cell lose its nucleus?
Answer
To leave **more room for haemoglobin**, so it can **carry more oxygen**.
Question
Why is a giant single-celled alga atypical?
Answer
It breaks the rule that cells are microscopic — a **single cell** can be **several centimetres long**.
Question
What is unusual about an aseptate fungal hypha?
Answer
It has **no cross-walls**, so the **cytoplasm is continuous** and **many nuclei are shared** along the thread.
Question
Are atypical features faults or adaptations?
Answer
**Adaptations** — each unusual feature usually helps the cell do a **specific job**.
Question
How can counting nuclei help spot an atypical cell?
Answer
**Zero** nuclei = anucleate; **many** nuclei = multinucleate; **one** nucleus = typical.
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Cell specialization
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