NCERT Solutions for Class 9th Science Chapter 2 Activity 2.4: Let us study — The Cell Interior
Book page 14 Updated on2026-09-19
Q1.
Study the given diagrams of a bacterial cell, a plant cell, and an animal cell (Fig. 2.10a, b and c). Observe the different structures present in each of them. Record your observations in Table 2.1.
Fig. 2.10 — (a) a typical bacterial cell, (b) a typical plant cell, and (c) a typical animal cell.
Table 2.1: Comparison of different kinds of cells based on their structure
S. No.
Cell structures
Bacterial cell
Plant cell
Animal cell
1.
Cell membrane
2.
Cell wall
3.
Cytoplasm
4.
Well-defined nucleus (genetic material enclosed by a membrane)
5.
Primitive nucleus or nucleoid (genetic material without membrane around it)
6.
Membrane-bound organelles
Answer
Here is Table 2.1 completed from Fig. 2.10.
S. No.
Cell structures
Bacterial cell
Plant cell
Animal cell
1.
Cell membrane
Present
Present
Present
2.
Cell wall
Present
Present
Absent
3.
Cytoplasm
Present
Present
Present
4.
Well-defined nucleus (genetic material enclosed by a membrane)
Absent
Present
Present
5.
Primitive nucleus or nucleoid (genetic material without membrane around it)
Present
Absent
Absent
6.
Membrane-bound organelles
Absent
Present
Present
Two more structures are visible in Fig. 2.10 and worth noting: the bacterial cell has an appendage for locomotion and free ribosomes; the plant cell alone has chloroplasts and a large central vacuole.
Why it happens: the pattern in the table is not a list of random differences — it splits cells into two kinds. Rows 4, 5 and 6 all move together: a cell either encloses its DNA in a nuclear membrane and has membrane-bound organelles, or it does neither. That is because both features depend on the same ability, namely to build internal membranes. Bacteria lack it, so their DNA lies free in the cytoplasm as a nucleoid and all their chemistry happens in one open compartment. Rows 1 and 3 are in every column because no cell can exist without a boundary and a fluid interior.
Tip: row 2 is the row that separates plants from animals, and rows 4–6 are the rows that separate bacteria from both. Read the table by rows, not by columns, and the logic appears.