Short type Questions with Answers from Invertebrate

(1) What is Cytopharynx ?

(Ans) :- In some Protozoan cells, a short passage like region through which food passes after being ingested at the cytostome.

(2) What is Pseudocoelom & where it is found ?

(Ans) :- A small second body cavity (the first being the gut) which occupies a space between the mesoderm of the body wall & the endoderm of the gut. There are no mesentaries suspending the internal organs & no muscular layers around the gut.
Found in Nematohelminthes.

(3) What is Amoeboid movement ?

(Ans) :- Movement in the fashion of Amoeba i.e. by Pseudopodia.

(4) What is contractile vacuole? Mention its function ?

(Ans) :- An organelle which appears to function in removal of excess water from the cells of Protozoa. The contractile vacuole expands as it fills with water from the cytoplasm & contracts as this water is emptied to the extertior.

Function :- They are responsible for osmoregulation, i.e. maintenance of a constant water potential inside the body.

 

(5) What is Tracheoles ? Where they are found ?

(Ans) :- One of the circular tubes that make up the respiratory system of an insect. The tracheae ramify throughout the body, terminating in fine, intracellular branches called Tracheoles.

(6) What is stone canal ? Where it is found ?

(Ans) :- In Echinoderm a canal with walls strengthened by calcarious matter that connect the madriporite with water vascular system.

(7) In which animal group Choanocytes are found ? Mention their function.

(Ans) :- One of the flagellated collar cells that line cavities & canals of sponges are called choanocytes.
In Poriferan animal Choanocytes are found.

Functions :- (a) Flagella of choanocytes maintain a current of environmental water through the canals(keep the water moving). (b) Trap & phagocytize food particles that are carried in the water.

(8) What is Medusa ?

(Ans) :- Medusa are usually free swimming stage in the life cycle of Cniderians. Medusa have bell shaped or umbrella shaped bodies & tetramerous symmetry, the mouth is usually centered on the concave side & tentacles extend from the rim of the umbrella.

(9) Name the different types of gills found in crustaceans?

(Ans) :- (a) Podobranch- attached with coxopodite of the thoracic appendage.
            (b) Arthrobranch- Attached with arthroidal membrane.
            (c) Pleurobranch- Attached with the lateral wall of the thorax.

(10) What is Radial Symmetry ? give example.

(Ans) :- Radial symmetry applies to the forms that can be devided into similar halves by more than two planespassing through the longitudinal axis.

Example :- Spongs, Hydra, Jellyfish etc.