Biology 1 Marks Question

It is the age pyramid which is increasing because the number of organisms in pre reproductive group is more than the reproductive and post reproductive group.

Temperature effects the absolute size of any animal and the relative proportion of various body parts because smaller animals have larger body surface area relative to their volume. That is why small animals in polar regions lose their body heat very rapidly. That's why very few small animals are capable to save their lives in polar regions.

Four adaptations are as follows:
(1) The epidermis of leaves and stem is thickly cutinized.
(ii) Presence of sunken stomata i.e. stomata are in deep pits example nerium.
(iii) Leaves are modified into spines.
(iv) A wax like coating is found on the stem and leaves epidermis which reduces the rate of transpiration.

Mangroves forests are found on the coast of tropical and subtropical regions. Their roots are called pneumatophores and they show viviparous seed germination. Example-Rhizo phora.

Predators keep the prey population under control. If there were no predators, the population density of prey species would become very high and ecosystem would become unstable.

The parasite and predator at benfitted while the host and prey suffer loss.

Burds and mammals.

Oysters and pelagic fishes.

Salmon fish in Pacific ocean and bamboo.

The ability of species to reproduce in the habitat they live in is called Darwinian ability.

The number of individuals in a population who have left their habitat and moved elsewhere during a given period of time is called emigration.

The number of individuals of a species who have arrived into a habitat from somewhere else during a given time period, is called immigration.

Percent cover or biomass is more suitable for measuring population size.

The shape of the pyramid reflects the growth status of the population, whether it is growing, stable or declining.

Biological control methods are based on prey regulating ability of the predator.

Ecological niche is the specific part of habitat occupied by the individuals of a species delimited by the individuals of species delimited by functioning of individuals in that ecosystem.

Predation is used to control the number of preys and to maintain the food chain

In mutualism, organisms living together are benefitted from each other whereas in commensalism one species gets benefitted and the other suffers neither benefit nor harm.