Question

Which of the following animal/s exhibit a holozoic mode of nutrition?
A. Amoeba
B. Paramoecium
C. Honey bee
D. All of the above

Answer 1

Holozoic nutrition is a type of heterotrophic nutrition which involves ingestion of liquid or solid food particles. It generally involves five processes - ingestion, digestion, absorption, assimilation and egestion.

Complete answer:
Amoeba engulfs food by the process of phagocytosis. It projects out finger-like projections of its body surface called pseudopodia towards the food particles forming a food vacuole. Complex substances are broken down into simple molecules by the help of digestive enzymes and finally get diffused in the cytoplasm. The unwanted waste products are thrown out from the cell surface. This type of nutrition is holozoic in nature. Hence, ‘option A’ is correct.
Paramoecium uses its cilia to engulf the food particles. Cilia are hair-like structures present on the surface of the body. When the food falls into the oral groove, cilia sweep the food into the gullet along with surrounding water to form a food vacuole. Food is digested inside the food vacuole using digestive enzymes and finally absorbed into the cytoplasm. Thee unwanted waste products are expelled out through anal pore. This type of nutrition is holozoic in nature. Hence, ‘option B’ is correct.
Honey bees collect nectar and pollen as food for the entire colony. Nectars get stored in their stomach known as ‘honey stomach’ or packing them in baskets on their rear legs. They pass down the nectars to one another until all the water is diminished. At this point, the nectar becomes honey and they store it in the cells of the honeycomb. This shows a holozoic mode of nutrition. Hence, ‘option C’ is correct.

Hence, the correct answer is option (D).

Note: Generally, there are three kinds of holozoic organisms depending upon what type of food they consume.
(i) Herbivores: The animals who consume plants as their food source.
Eg, cow, elephant
(ii) Carnivores: The animals who feed on other animals for their food source.
Eg. Lion, wolf
(iii) Omnivores: The animals who consume both plants and animals as their food source.
Eg, Crow, ant