Which of the following is correct about nematocyst?
It can be re-used.
It is excretory organ in arthropods.
It is ejected on contact and pierce the prey.
None of these.
C.
It is ejected on contact and pierce the prey.
Nematocysts are the stinging cells and are the organs of offence and defence of coelenterates. They contain a poisonous proteinaceous fluid hypnotoxin, alongwith the tube that injects the fluid into the victim. Nemaocysts are activated in response to chemicals secreted by prey. They explode after coming in contact with the prey.
Assertion : Salamander, Sphenodon are classified as amphibians.
Reason : Sphenodon is regarded as living fossil.
If both Assertion and Reason are true and Reason is the correct explantion of Assertion
If both Assertion and Reason are true and Reason is not the correct explanation of Assertion
If Assertion is true but Reason is false
If Assertion is false but Reason is true
Functional systems for specific physiological functions are not seen in
Annelids
Molluscs
Arthropods
Echinoderms
Echinoderms
Match Column I with Column II and choose the correct answer
Column I | Column II |
i. Incomplete digestive system | A. Sponges |
ii. Cellular level of organization | B. Coelenterates |
iii. Radial symmetry | C. Annelids |
iv. Pseudocoelomate | D. Platyhelminthes |
v. Metamerism | E. Aschelminthes |
i - C; ii - D; iii - A; iv - B; v - E
i - D; ii - E; iii - B; iv - C; v - A
i - D; ii - A; iii - B; iv - E; v - C
i - A; ii - B; iii - C; iv - D; v - E
i - A; ii - B; iii - C; iv - D; v - E
Which of the following statement/s regarding coelenterates is/ are wrong?
I. Cnidocytes are present on the tentacles and on the body
II. Diploblastic with cellular level of organization
III. Polyp forms are free swimming
IV. Exhibits metagenesis
V. Polyps produce medusae sexually and medusae form polyps asexually
II and IV only
III and V only
I, II and III only
III only
III only
Choose the wrong statement
Teeth in Chondrichthyes are modified ctenoid scales
Air bladder in fishes regulates buoyancy
In amphibians, the tympanum represents the ear
Long bones in birds are pneumatic
Long bones in birds are pneumatic
Match the following and choose the correct combination from the options given.
Column I | Column II |
A. Saprophytic protists | 1. Trypanosoma |
B. Golden algae | 2. Plasmodium |
C. Malarial parasite | 3. Desmids |
D. Sleeping sickness is caused by | 4. Slime moulds |
A - 1; B - 2; C - 3; D - 4
A - 2; B - 3; C - 4; D - 1
A - 4; B - 3; C - 2; D - 1
A - 3; B - 4; C - 2; D - 1
A - 3; B - 4; C - 2; D - 1
Flame cells of flatworms help in
(i) osmoregulation
(ii) digestion
(iii) reproduction
(iv) excretion
(v) bioluminescence
(ii) only is correct
(i) and (iv) are correct
(iii) only is correct
(i) and (v) are correct
(i) and (v) are correct
Read the statements regarding echinoderms and choose the correct option
(1) All are marine with organ system level of organisation.
(2) Adults are bilaterally symmetrical.
(3) They are dioecious.
(4) Fertilisation is internal and indirect development is observed.
(5) Triploblastic and acoelomate animals.
(1) and (3) are correct
(5) alone is correct
(1), (3) and (5) are correct
(1) and (5) are correct
(1) and (5) are correct
This class of animals are all ectoparasites on some fishes
Amphibia
Osteichthyes
Reptilia
Cyclostomata
Cyclostomata