The following table shows some features of animals. Which features would describe a bird?

Here are the solutions to the questions:

Question 3:

• Which features would describe a bird? Birds are characterized by the presence of feathers and wings. They do not have gills (which are for aquatic respiration) or hair (which is a mammalian feature).

  • Feathers: Present (✓)
  • Gills: Not present (X)
  • Hair: Not present (X)
  • Wings: Present (✓) Comparing these features to the table:
  • Row A: X, ✓, ✓, X (Incorrect)
  • Row B: ✓, ✓, X, X (Incorrect)
  • Row C: ✓, X, X, ✓ (Correct)
  • Row D: X, X, ✓, ✓ (Incorrect)

  The correct option is C.

Question 4:

• The diagram shows some animal cells as seen under a light microscope. How many cell walls are visible? The diagram shows several cells with irregular shapes and internal nuclei. These are identified as animal cells. Animal cells do not possess cell walls; cell walls are a characteristic feature of plant cells, fungi, bacteria, and algae. Therefore, no cell walls are visible in the diagram.

  The correct option is A) 0.

Question 5:

• In the table the rows show the number of chloroplasts visible in three different types of cells found in a leaf. Which row shows the most likely numbers in the three types of cells found in a leaf?

  • Epidermis: Epidermal cells primarily function in protection and do not typically contain chloroplasts (except for guard cells, which are specialized). So, the number of chloroplasts should be 0.
  • Mesophyll: Mesophyll cells (palisade and spongy mesophyll) are the primary site of photosynthesis in a leaf and are rich in chloroplasts. So, the number of chloroplasts should be high.
  • Phloem sieve tube: Phloem sieve tube elements are specialized for transporting sugars and lack most organelles, including chloroplasts, to maximize space for sap flow. So, the number of chloroplasts should be 0.

  Let's evaluate the options based on these facts:

  • A: Epidermis (0), Mesophyll (6), Phloem sieve tube (17) - Incorrect, phloem sieve tubes have 0 chloroplasts.
  • B: Epidermis (0), Mesophyll (17), Phloem sieve tube (0) - Correct, this matches the expected distribution.
  • C: Epidermis (17), Mesophyll (6), Phloem sieve tube (0) - Incorrect, epidermis has 0 chloroplasts.
  • D: Epidermis (17), Mesophyll (0), Phloem sieve tube (6) - Incorrect, epidermis has 0 and mesophyll has many chloroplasts.

  The correct option is B.