11. The viruses in an attenuated vaccine?
[A] have no genome
[B] continue to replicate
[C] are usually larger than bacteria
[D] is altered with chemicals
Show Answer
Correct Answer: B [continue to replicate]
Notes:
The viruses in an attenuated vaccine continue to replicate. Attenuated vaccines do not usually cause disease like those caused by the wild form of the organism.
12. The lysogenic state is controlled by the activity of the regulatory region of the lambda phage genome, this region is called?
[A] immunity repressor
[B] immunity operon
[C] operon repressor
[D] none of these
Show Answer
Correct Answer: B [immunity operon]
Notes:
The lysogenic state is controlled by the activity of the regulatory region of the lambda phage genome, this region is called immunity operon.
13. Which is not an exception in angiosperms?
[A] Double fertilization
[B] Secondary growth
[C] Presence of vessels
[D] Autotrophic nutrition
Show Answer
Correct Answer: A [Double fertilization]
Notes:
Angiosperms are plants that produce flowers. They hold their seeds in the fruits. They are the largest and most diverse group within the Plantae kingdom, with approximately 300,000 species. Double fertilization is a characteristic of angiosperms in which both a diploid zygote and a triploid endosperm are formed in this process of green fertilization.
14. The cell wall of Spirogyra contains__?
[A] Cellulose
[B] Chitin
[C] Lignin
[D] Suberin
Show Answer
Correct Answer: B [Chitin]
Notes:
Chitin is used to build the cell wall. Each cell of Spirogyra is surrounded by a two-layered cell wall.
15. Cooci which are mostly single or in pairs are called?
[A] Streptococci
[B] Diplococci
[C] Tetracocci
[D] None of these
Show Answer
Correct Answer: B [Diplococci]
Notes:
A diplococcus is a round bacterium (a coccus). It usually occurs as two joined cells.
16. Which of the following occurs in Bryophytes?
[A] Great economic value
[B] No value at all
[C] Great ecological importance
[D] A lot of aesthetic value
Show Answer
Correct Answer: C [Great ecological importance]
Notes:
They are called pollution indicators. These prevent soil erosion by running water.
17. What is the pollination medium in Malacophilous?
[A] bats
[B] water
[C] air
[D] snails
Show Answer
Correct Answer: D [snails]
Notes:
Snails are the pollination medium in Malacophilous. Pollination is the process in which the pollens are transferred from anther to stigma.
18. Which is the innermost tissue and gives rise to the xylem and phloem?
[A] Protoderm
[B] Procambium
[C] Ground Meristem
[D] Promeristem
Show Answer
Correct Answer: B [Procambium]
Notes:
Procambium is the innermost tissue and gives rise to the xylem and phloem. It helps in transporting water and nutrients to different parts of the plant.
19. A structure in the plant’s male reproductive organ where the development of pollen takes place is called__.
[A] Microsporangium
[B] Somatic hybridization
[C] Sporulation
[D] Apomixis
Show Answer
Correct Answer: A [Microsporangium]
Notes:
A structure in the plant’s male reproductive organ where the development of pollen takes place is called Microsporangium. It is surrounded by four layers: Epidermis, Endothecium, Middle layers, Tapetum.
20. Late blight of tomato is caused by __.
[A] Phytophthora cactorum
[B] Phytophthora cambivora
[C] Phytophthora infestan
[D] Phytophthora citrophthora
Show Answer
Correct Answer: C [Phytophthora infestan]
Notes:
Tomato late blight is caused by the pathogen Phytophthora infestans. Late blight can occur at any time during the growing season when the weather is cool and wet.
