Question

Thigmotaxis does not occur in
(a)Hydra
(b)Paramaecium
(c)Ascaris
(d)Amoeba

Answer 1

Hint: This is an intestinal parasite of humans. It is the most common human worm infection. The larvae and adult worms live in our small intestine and may cause intestinal disease.

Complete answer:
Thigmotaxis is defined as a phenomenon of touch, in which the organism feels stimulus within the organism when it touches a rock or sand or anything. It is not exhibited by the Ascaris.

Additional Information: -Both male and female Ascaris elongated cylindrical bodies that taper at both ends, but only in males, the tail is curved ventrally.
-Ancylostoma duodenale also known as intestinal hookworm. The larva matures into an adult within the intestine (jejunum mainly), where they attach to the villi, and feminine worms can lay 25,000 eggs per day. The eggs are released with the faeces and reside on soil; when soil becomes warm, moist, a larva rapidly develops within the egg and hatches after 1 to 2 days.
-Enterobius vermicularis is also known as human pinworm. The eggs of pinworm measure 50—60 µm by 20—30 µm. They are transparent, elongate to oval in shape, and slightly flattened on one side.
-Necator Americans are a species of hookworm. They are associated with blood loss and anaemia. Patients who are infected with around 25 to 100 worms experience symptoms like fatigue, weight loss, and slight headaches.
So, the correct answer is, ‘Ascaris.’

Note: Ascariasis is an infection of the small intestine seen in humans, caused by Ascaris lumbricoides, which is a species of roundworm. Roundworms are a kind of parasitic worm. Infections caused by roundworms are common. Ascariasis is the most common roundworm infection seen in all types of ages. In mild or moderate ascariasis, the intestinal infestation can cause Vague abdominal pain, nausea and vomiting diarrhoea or bloody stools.