Some statements about cells are listed.

Question

1. All living cells must have a cell wall.

2. All living cells require oxygen for survival.

3. The basic unit of life is a cell.

Which of these ideas are included in cell theory?
Responses
A 1 only1 only
B 1 and 31 and 3
C 2 and 32 and 3
D 3 only3 only

Answer 1

The correct response is D: 3 only.

Cell theory includes the idea that the basic unit of life is a cell (statement 3). However, statement 1 (not all living cells have a cell wall, as animal cells do not) and statement 2 (not all living cells require oxygen; for example, anaerobic bacteria do not) are not part of cell theory.