Biology Multiple Choice Questions on “Animals Structural Organisations – Earthworm – 1”.
1. Earthworm is a(n) ______
a) terrestrial vertebrate
b) aquatic vertebrate
c) aquatic invertebrate
d) terrestrial invertebrate
Answer: d
Clarification: Earthworm is a long cylindrical worm belonging to class Annelida. It does not have a backbone and hence it is an invertebrate. It is terrestrial and inhabits the upper layers of the soil.
2. Which of the following statements about earthworms is true?
a) They are vertebrates
b) They do not live in burrows
c) They can be traced by fecal deposits
d) They inhabit the lower layers of the soil
Answer: c
Clarification: Earthworms can be traced by fecal deposits or worm castings. They are invertebrates as they lack a backbone and a bony skeleton. They live in burrows in the upper layers of the soil.
3. What are the common Indian earthworms?
a) Lacertilia, Pheretima
b) Periplaneta, Lumbricus
c) Pheretima, Lumbricus
d) Periplaneta, Pheretima
Answer: c
Clarification: Pheretima and Lumbricus are the common Indian earthworms. It is a terrestrial invertebrate with a long cylindrical body. Periplaneta is a genus of the cockroach family, while Lacertilia is the genus of the lizard family.
4. What is the median mid dorsal line present along the length of an earthworm?
a) Dorsal blood vessel
b) Dorsal root ganglion
c) Prostomium
d) Clitellum
Answer: a
Clarification: The dorsal blood vessel is present along the length of the earthworm’s body. It is seen as a dark median line. Prostomium covers the mouth while clitellum is a band of glandular tissue covering the 14th to 16th segments.
5. Which of the following statements is true about prostomium?
a) It is present in the posterior end of the earthworm
b) It acts as a wedge to open cracks in the soil
c) It is the mouth of the earthworm
d) It does not have a sensory function
Answer: b
Clarification: The prostomium is located in the anterior end of the earthworm. It is a covering of the mouth and has a sensory function. It also acts as a wedge to open cracks in the soil. It is the first segment of the body of the earthworm.
6. The first body segment of the earthworm is the _____
a) male genital aperture
b) female genital aperture
c) peristomium
d) clitellum
Answer: c
Clarification: Peristomium or buccal segment is the first body segment of the earthworm. It is the mouth part. The genital apertures and clitellum are located towards the middle of the body of the earthworm.
7. Clitellum is a ______
a) glandular tissue
b) muscular tissue
c) neural tissue
d) connective tissue
Answer: a
Clarification: Clitellum is a glandular tissue. It appears as a prominent dark band. The clitellum covers the 14th to 16th segment of the body of the mature earthworm. This glandular tissue contains secretory cells.
8. What is present on the 5th to 9th segments of the earthworm’s body?
a) Clitellum
b) Peristomium
c) Female genital pore
d) Spermathecal apertures
Answer: d
Clarification: On the sides of the intersegmental grooves of the 5th to 9th segment, spermathecal apertures are present. They are eight in number. The peristomium is the first segment while the clitellum is the glandular tissue covering the 14th to 16th segment.
9. Where is the female genital pore present in earthworm?
a) 16th segment
b) 18th segment
c) 14th segment
d) 9th segment
Answer: c
Clarification: The female genital pore of the earthworm is present in the mid – ventral line of the 14th segment. It is a single pore. The male genital pores are two in number. It is present on the 18th segment. Earthworms are hermaphrodites.
10. Where are the male genital pores present in earthworm?
a) 16th segment
b) 18th segment
c) 14th segment
d) 9th segment
Answer: b
Clarification: The male genital pores of the earthworm are present on the ventral lateral sides of the 18th segment. They are two in number. The earthworm also contains a female genital pore as it is a hermaphrodite.
11. What is the main role of setae in earthworm?
a) Storage of food
b) Respiration
c) Reproduction
d) Locomotion
Answer: d
Clarification: The principal role of setae in earthworm is locomotion. It is present in every body segment except the first, the last and the clitellum. Reproduction is carried out by the female and male genital pores present at other segments.
12. What are the pores present on the surface of the body of the earthworm called?
a) Polypore
b) Exospore
c) Nephridiopore
d) Zoospore
Answer: c
Clarification: Nephridiopore is present on the surface of the earthworm’s body. They are numerous in number. They are minute in size. Polypore, exospore and zoospore are not associated with earthworm but with fungi.
13. Identify the part of earthworm shown in the picture below.
a) Female genital pore
b) Male genital pore
c) Anus
d) Clitellum
Answer: c
Clarification: The anus is the last segment of the earthworm. Since the mouth segment peristomium is shown, it implies that the segment at the opposite end should be the anus. The female and male genital pores and the clitellum are located in the middle of the body.
14. The epidermal pits in the middle of each segment of the earthworm contains _____
a) setae
b) clitellum
c) nephridiopores
d) typhlosole
Answer: a
Clarification: The location of setae is mid – segmental in the epidermal pits. They are S – shaped and present in rows. The main function of the setae is to help with locomotion. They are extendable and retractable.
15. Which of the following statements is true about setae present in earthworm?
a) They are used for reproduction
b) They are retractable
c) They are L – shaped
d) They cannot be extended
Answer: b
Clarification: Setae are both extendable and retractable. They are S – shaped and present in the epidermal pits in the mid – segmental region of every segment. The principal function of the setae is locomotion.