Certain unicellular eukaryotes, including diatoms and some yeasts, have mechanisms of nuclear division that may resemble intermediate steps in the evolution of mitosis. Which of the following is a characteristic feature of nuclear division in these organisms?

#Question id: 11265

#Unit 10. Ecological Principles

Approximately how many kg of carnivore production can be supported by a field plot containing 2000 kg of plant material?

#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