21. In which there are two forms of polyp or medusa?
[A] Cnidaria
[B] Platyhelminthes
[C] Aschelminthes
[D] Ctenophora
Show Answer
Correct Answer: A [Cnidaria]
Notes:
In Cnidaria, there are two forms of polyp (sessile and cylindrical) or medusa.
22. Excretion in flatworms is done by__
[A] protonephridia
[B] flame cells
[C] green glands
[D] malpighian tubules
Show Answer
Correct Answer: B [flame cells]
Notes:
Excretion in flatworms is done by flame cells. A flame cell is a specialized emitting cell. It is found in most simple freshwater invertebrates, including flatworms, rotifers, and nemertians.
23. How many chambers are there in the heart of fish?
[A] 1
[B] 2
[C] 3
[D] 4
Show Answer
Correct Answer: B [2]
Notes:
Fish have a two-chambered heart. The heart has one atrium and one ventricle.
24. Frogs and toads are examples of which of the following amphibians?
[A] Anura
[B] Urodela
[C] Apoda
[D] None of these
Show Answer
Correct Answer: A [Anura]
Notes:
Frogs and toads are examples of Anura amphibians. There are about 3400 species of Anura in the world.
25. Ruminants belong to which of the following order?
[A] Proboscida
[B] Artiodactyla
[C] Marsupials
[D] Edentata
Show Answer
Correct Answer: B [Artiodactyla]
Notes:
Ruminants belong to Artiodactyla order. Artiodactyla together with whales make up the order Cetartiodactyla. Artiodactyla includes omnivores and herbivores.
26. Which is the heaviest organ of the human body?
[A] skin
[B] liver
[C] brain
[D] bone
Show Answer
Correct Answer: A [skin]
Notes:
Skin is the heaviest organ of the human body. Its weight is around 4.5 kg.
27. What is the speed of nerve impulses?
[A] 60 m/s
[B] 0.5 – 130 m/s
[C] 10-30 m/s
[D] 50 -150 m/s
Show Answer
Correct Answer: B [0.5 – 130 m/s]
Notes:
The speed of nerve impulses is 0.5 – 130 m/s. A nerve impulse or action potential is an electrical signal. It travels through the membranes of neurons.
28. The auditory nerve carries:
[A] Smell information
[B] Taste information
[C] Balance information
[D] Sound information
Show Answer
Correct Answer: D [Sound information]
Notes:
The auditory nerve carries Sound information. The acoustic nerve is a sensory nerve essential for hearing. It is also called the cochlear nerve.
29. Apart from the brain, what does the skull protect?
[A] the lungs
[B] the diaphragm
[C] the body’s cells
[D] the sense organs
Show Answer
Correct Answer: D [the sense organs]
Notes:
The skull, or cranium, also protects the eyes, nose, ears and mouth. There are holes in the skull that allow these senses to pick up light, sound and smell.
30. Which of the following is one of the innermost and thinnest layers of arteries and veins?
[A] Tunica Media
[B] Tunica Intima
[C] Tunica Externa
[D] None of these
Show Answer
Correct Answer: B [Tunica Intima]
Notes:
Tunica Intima is one of the innermost and thinnest layers of arteries and veins. It contains endothelial cells. They are in direct contact with the bloodstream.
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