11. Which one of the following statements is not correct? (UPSC Prelims 2002)
[A] All echinoderms are viviparous
[B] Round worm has no circulatory system
[C] In bony fishes, swim bladder is usually present
[D] In cartilaginous fishes, fertilisation is internal
Show Answer
Correct Answer: A [All echinoderms are viviparous]
Notes:
Echinoderm is the common name given to any member of the phylum Echinodermata of marine animals. The adults are recognizable by their radial symmetry, and include such well-known animals as starfish, sea urchins, sand dollars, and sea cucumbers, as well as the sea lilies or “stone lilies”.
The sexes are separate except few echinoderm species. There is no sexual dimorphism. Fertilization is external and few forms are viviparous.
12. Consider the following conditions of sick human body
1. Swollen lymph nodes
2. Sweating at night
3. Loss of memory
4. Loss of weight
Which of these are the symptoms of AIDS? (UPSC Prelims 2003)
[A] 1 and 2
[B] 2, 3 and 4
[C] 1, 2 and 3
[D] 1, 2, 3 and 4
Show Answer
Correct Answer: D [1, 2, 3 and 4]
Notes:
AIDS is a viral disease. In this disease the immune system weakens and the body becomes prone to different type of infection by pathogens. Sweating at night, swollen lymph nodes, loss of memory and loss of weight are also symptoms of AIDS.
13. Which among the following blood groups is referred as the universal donor blood group?
[A] O -ve
[B] O +ve
[C] AB -ve
[D] AB +ve
Show Answer
Correct Answer: A [O -ve]
Notes:
The person with O-ve blood group is considered as the universal donor. Whereas a person with O +ve is not a universal donor as O +ve consists of Rh(Rhesus) factor which makes it incompatible for Rh -ve bloods.
14. Which part of the human body is affected by Alziemer’s disease?
[A] Brain
[B] Lungs
[C] Heart
[D] Kidneys
Show Answer
Correct Answer: A [Brain]
Notes:
Alziemer’s is a disease which attacks the neural system, It results in continuous decline in the number brain cells which leads to loss of memory.
15. Hugo de Vries is related to which of the following theory of biology?
[A] aquatic ape theory
[B] modern anatomy
[C] Mutation Theory
[D] theory of evolution
Show Answer
Correct Answer: C [Mutation Theory]
Notes:
Hugo de Vries is a Dutch botanist and geneticist who pioneered the experimental study of biological evolution. His rediscovery of Gregor Mendel’s principles of heredity and his theory of biological mutation in 1900.
16. Protein is made up of which of the following?
[A] Sugar
[B] Amino acid
[C] Carbohydrate
[D] Fatty acid
Show Answer
Correct Answer: B [Amino acid
]
Notes:
All proteins are linked by a peptide link and are polymers of amino acids. Amino acid is the building block of protein.
17. Which disinfectant is effective against viruses?
[A] Hydrogen peroxide
[B] Hypochlorite
[C] Formaldehyde
[D] All of these
Show Answer
Correct Answer: D [All of these]
Notes:
Hydrogen peroxide, Hypochlorite and Formaldehyde are disinfectants is effective against viruses.
18. Which bacteria do not have a cell wall and are therefore resistant to penicillin?
[A] Cyanobacteria
[B] Mycoplasmas
[C] Bdellovibrios
[D] Spirochetes
Show Answer
Correct Answer: B [Mycoplasmas]
Notes:
Mycoplasma is a genus of bacteria that do not have a cell wall surrounding the cell membrane.
19. Where is teichoic acid commonly found?
[A] cell walls of gram positive bacteria
[B] outer membranes of gram positive bacteria
[C] cell walls of gram negative bacteria
[D] outer membranes of gram negative bacteria
Show Answer
Correct Answer: A [cell walls of gram positive bacteria]
Notes:
Teichoic acid is found within the cell wall of most Gram-positive bacteria. It appears to extend to the surface of the peptidoglycan layer, and species in the genera Staphylococcus, Streptococcus, Bacillus, Clostridium, Corynebacterium and Listeria.
20. A bryophyte that has nitrogen-fixing blue-green algae in its thallus is__?
[A] Pogonatum
[B] Riccia
[C] Marchantia
[D] Anthoceros
Show Answer
Correct Answer: D [Anthoceros]
Notes:
A bryophyte that has nitrogen-fixing blue-green algae in its thallus is Anthoceros. Species of Anthoceros have a small to medium-sized green thallus.
