Autotrophs in the aquatic ecosystem, unlike their counterparts in the terrestrial ecosystem are mostly microscopic and very low in indigestible (to the herbivores) matter. Following some observation are given? 

A) Tropic level transfer efficiency is greater in aquatic ecosystem than terrestrial ecosystem  

B) Tropical forest herbivores have higher consumption efficiencies than grassland herbivores

C) Flow of energy and nutrient is rapidly in aquatic ecosystem than terrestrial

D) Production efficiency of higher tropic level is greater than lower tropic level

#Question id: 2237

#Unit 2. Cellular Organization

Glucose enters erythrocytes via a GLUT-1 uniporter. As the levels of glucose in the bloodstream decrease between meals, what happens to the glucose in the cells?

#Question id: 2238

#Unit 2. Cellular Organization

Consider the transport of glucose into an erythrocyte by facilitated diffusion.  When the glucose concentrations are 5 mM on the outside and 0.1 mM on the inside, the free-energy change for glucose uptake into the cell is:  (These values may be of use to you:  R = 8.315 J/mol·K; T = 298 K; 9 (Faraday constant) = 96,480 J/V; N = 6.022×10²³ /mol.)

#Question id: 2239

#Unit 2. Cellular Organization

Consider the transport of K+ from the blood (where its concentration is about 4 mM) into an erythrocyte that contains 150 mM K+.  The transmembrane potential is about 60 mV, inside negative relative to outside.  The free-energy change for this transport process is:  (These values may be of use to you:  R = 8.315 J/mol.K; T = 298 K; 9 (Faraday constant) = 96,480 J/V; N = 6.022×10²³ /mol.)

#Question id: 2240

#Unit 2. Cellular Organization

 In which of the following cases is energy NOT needed for transmembrane transport?

a. Lysine moves into the cell against its concentration gradient via the Na+/lysine symporter.

b. Potassium ions (K+) move out of the cell down the K+ concentration gradient via potassium channels.

c. Glucose moves into the cell down its concentration gradient via a glucose uniporter.

d. Sodium ions (Na+) move out of the cell down the Na+ concentration gradient via sodium channels.

Which of the following are correct?

#Question id: 2241

#Unit 2. Cellular Organization

Which of the following statement(s) is (are) true of V-class proton pumps?

#Question id: 2242

#Unit 2. Cellular Organization

What two features of the structure of cholesterol make it somewhat amphipathic?