Cell specialisation and organisation (cells → tissues → organs)
Understand cell differentiation, learn key specialised cells, and use the organisation hierarchy confidently.
Teach (quick)
Cell differentiation
Cell differentiation is when a cell changes to become specialised for a particular function.
- Animals: most differentiation happens early.
- Plants: many cells can still differentiate later.
Specialised cells (learn the adaptations)
- Sperm cell: tail for swimming; lots of mitochondria for energy.
- Nerve cell: long axon to carry electrical signals.
- Muscle cell: can contract (many mitochondria).
- Root hair cell: large surface area to absorb water/minerals.
Organisation levels
- Cells → tissues → organs → organ systems
Example: muscle cell → muscle tissue → heart → circulatory system.
Stem cells
Stem cells can divide and then differentiate into other cell types.
Practice
MCQ
- A tissue is…
- A a group of organs working together
- B a group of similar cells working together
- C a single specialised cell
- D a group of different organ systems
- Which is an adaptation of a sperm cell?
- A chloroplasts
- B tail
- C cell wall
- D large vacuole
- Which statement about plant cells is correct?
- A plant cells never differentiate
- B plant cells can only differentiate before birth
- C plant cells can differentiate throughout life
- D plant cells have no specialised cells
- Which sequence is correct?
- A organ → tissue → cell → organ system
- B cell → tissue → organ → organ system
- C cell → organ → tissue → organ system
- D tissue → cell → organ → organ system
Short answer
-
Define cell differentiation. (1)
-
Explain one adaptation of a root hair cell. (2)
-
Give one benefit and one ethical issue of using embryonic stem cells. (2)
Mark scheme (condensed)
- Differentiation: cell becomes specialised
- Root hair: large surface area / thin cell wall / many mitochondria (for active transport)
- Benefit: treat disease / replace damaged cells
- Ethical: embryo destroyed / moral/religious objections