When the population density reaches the carrying capacity, the logistic growth curve is said to be in:

1. Lag phase

2. A phase of acceleration

3. A phase of deceleration

4. Asymptote

In general, which of the following is not an adaptation seen in parasites in accordance with their life style?

1. Loss of unnecessary sense organs

2. Presence of adhesive organs

3. Low reproductive capacity

4. Loss of digestive system

I. Organisms living in oceans, lakes and rivers face water-related problems.
II. Euryhaline can tolerate a wide range of salinities
III. Stenohaline are restricted to a narrow range of salinities
IV. No fresh water animals cannot live for long in sea water but sea animals can live in fresh water for long time because of osmotic balance
V. The salt concentration is less than 5% in inland water, 30-35% in sea and >100% in some hypersaline lagoons.

(1) All are correct                     

(2) All are false

(3) Only IV is wrong                 

(4) Only I, III, V are correct

Which of the following term implies the maintenance of relatively constant physical and chemical conditions with organisms?

(1) Homeostasis   

(2) Adaptation      

(3) Isometry         

(4) Acclimation

Human can get homeostasis through:

(1) Only physiological means

(2) Only physical means

(3) Both physiological and physical means

(4) Neither physiological nor physical means

Which of the following statement is false?
(1) Osmoconformors are able to maintain homeostasis by physiological means or sometimes behavioural means also which ensure constant body temperature, constant osmotic concentration etc
(2) All birds and mammals, and a very few lower vertebrates and invertebrates are capable of osmoregulation and thermoregulation
(3) Thermoregulation is the major reason of the success mammals
(4) Sweating and shivering are the means of thermoregulation by humans

Why small animals are not found in polar area mostly?

(1) Because they have a smaller surface area relative to their volume

(2) Because they have a larger volume relative to their surface area

(3) Because they have a smaller metabolic rate

(4) Because they have a larger surface area relative to their volume

Kangaroo rats:

(1) Have a generalized diet               

(2) Avoid eating fats

(3) Do not need to drink water          

(4) Are insensitive to heat

Find out false one:
(a) Mammals from colder climate generally have shorter ears and limbs to minimise heat loss
(b) All organisms have behavioural adaptations that allow them to respond quickly to a stressful situation
(c) Some organisms possess adaptations that are physiological which allow them to respond quickly to a stressful situation
(d) A large variety of invertebrates and fish live at great depths in the ocean where the pressure could be > 100 times than the normal atmospheric pressure

Which of the following statement is false with respect to adaptations?
(1) Many xerophytic plants have thick cuticle on leaf epidermis, sunken stomata
(2) Some xerophytic plants have special photosynthetic pathway (CAM) that enables their stomata close during day
(3) Opuntia has spines (modified leaves), photosynthetic phylloclade (stem)
(4) All adaptations are genetically fixed all organisms