In general, the hormones that regulate senescence can be divided into two basic categories based on their most commonly observed effects:

I) positive (promoting) senescence regulators and

II) negative (repressing) senescence regulators

a) Hormones involved-Ethylene, Abscisic acid (ABA)

b) Hormones involved-Brassinosteroids (BRs), Salicylic acid (SA), Jasmonic acid (JA)

c) Hormones involved-Cytokinin, Auxin, Gibberellin (GAs)

Select correct combinations from given hormones which are involved in regulators?

#Question id: 11266

#Unit 10. Ecological Principles

Which of the following options lists ecosystems in increasing order of consumption efficiency of herbivore?

#Question id: 11276

#Unit 10. Ecological Principles

Following statement regarding efficiency at different tropic level for secondary production?

A-high production efficiency individual able to survive at little food

B-production efficiency decrease toward increase tropic level 

C-aquatic herbivore is more efficient grazer than terrestrial grazer

D- Carnivore assimilation efficiency appear to average around 10%

Which above combination are correct?

#Question id: 11277

#Unit 10. Ecological Principles

If a species is a keystone predator, then its removal from a community should

(A) Increase population size of the predator’s preferred prey

(B) decrease species diversity in the prey community

(C) decrease productivity of the predator’s preferred prey

(D) increase species diversity in the prey community

#Question id: 11278

#Unit 10. Ecological Principles

Which of the following is true with respect to oligotrophic lakes and eutrophic lakes?

A) Oligotrophic lakes are less subject to oxygen depletion.

B) Rates of photosynthesis are lower in eutrophic lakes.

C) Eutrophic lake water contains higher concentrations of nutrients.

D)Sediments in oligotrophic lakes contain larger amounts of decomposable organic matter.

#Question id: 11279

#Unit 10. Ecological Principles

Ecosystem A: Actual link 10, number of species 15  

Ecosystem B: Actual link 10, number of species 20   

Connectance of ecosystem A and B

#Question id: 11280

#Unit 10. Ecological Principles

Ecosystem services include processes that increase the quality of the abiotic environment. Which of the following processes would fall under this category?