64
All the following organelles have membranes except
- A. nucleus
- B. vacuole
- C. cell membrane
- D. cell wall
65
The hydra has two body layers of cells called
- A. ectodermis and enteron
- B. ectoderm and endoderm
- C. endodermis and dermis
- D. epidermis and dermis
66
Which of the following best describes a colony of volvox?
- A. Asexually reproduced cells held together in a mass, but independent of each other
- B. Sexually reproduced cells held together in a mass, and dependent on each other
- C. Single free-living acellular units irrespective of their parental origin
- D. Several units of cells, held together by cytoplasmic strands and dependent on each other
67
Amoeba obtains its oxygen requirements
- A. from oxidising food substances
- B. from air trapped in vacuoles
- C. through diffusion of air into its body
- D. through an air cavity in the ectoplasm