Biology Multiple Choice Questions on “Organisms and Populations – Responses to Abiotic Factors – 1”.
1. What is the organism in which body temperature and the osmotic concentration of the body fluid changes with the ambient temperature and change with that of the ambient water osmotic concentration respectively called?
a) Regulators
b) Conformers
c) Migratory
d) Hibernating
Answer: b
Clarification: Conformers are the poikilotherms that are the organisms in which body temperature changes with the ambient temperature and in aquatic animals, the osmotic concentration of the body fluid change with that of the ambient water osmotic concentration. Some examples are Insects, lizards, fishes, etc.
2. What organisms are able to maintain homeostasis which ensures a constant body temperature, constant osmotic concentration, etc., are called?
a) Regulators
b) Conformers
c) Migratory
d) Hibernating
Answer: a
Clarification: The warm-blooded animals are those who are able to maintain homeostasis by physiological (sometimes behavioral also) means which ensure constant body temperature, constant osmotic concentration, etc. They are also called as regulators. Some examples are mammals, birds, etc.
3. Which of the following organisms are capable of osmoregulation as well as thermoregulation?
a) Cactus
b) All mammals
c) Bryophytes
d) Angiosperms
Answer: b
Clarification: All mammals are capable of thermoregulation and osmoregulation. Thermoregulation is the ability to maintain constant body temperature under changing environmental temperatures while osmoregulation is the ability to maintain a constant osmotic concentration of body fluids under high solute concentrations.
4. According to evolutionary biologists why mammals are successful?
a) Expression of thoughts
b) Constant osmotic concentration
c) Right of speech
d) Constant body temperature
Answer: d
Clarification: According to evolutionary biologists mammals are successful because they have the ability to maintain constant body temperature. They are warm-blooded animals and also called as endotherms or regulators.
5. For which of the following organisms thermoregulation is energetically expensive?
a) Large animals
b) Elephants
c) Humming birds
d) Man
Answer: c
Clarification: Thermoregulation is energetically expensive to humming birds because of their small size. The smaller is the animals; more is the heat loss from the body. Thermoregulation is energetically expensive for small animals and shrews.
6. In which of the following organisms various kinds of thick-walled spores which help them survive unfavorable conditions and germinate on the availability of suitable environment found?
a) Humans
b) Fungi
c) Banyan
d) Mango
Answer: b
Clarification: Fungi produce various kinds of thick-walled spores that help to survive unfavorable conditions and germinate on the availability of a suitable environment. Along with these such spores are also produced by bacteria, lower plants, and algae.
7. Which structure in higher plants serves as a means to overcome a period of dormancy, stress and then helps in dispersal?
a) Spores
b) Petals
c) Sepals
d) Seed
Answer: d
Clarification: Seeds in higher plants serve as a means to tide over a period of stress and also helping in dispersal. A seed is an embryonic plant, a viable offspring that is enclosed in the protective outer covering.
8. In which state do zooplankton species in lakes and ponds enter under unfavorable conditions?
a) Diapause
b) Aestivation
c) Hibernation
d) Speciation