#Question id: 11374
#Unit 9. Diversity of Life Forms
Which of the following use light energy to generate ATP, but do not release oxygen?
#Question id: 11324
#Unit 10. Ecological Principles
Many temperate lakes develop pronounced thermal stratification during the summer months. In which zone of such lakes does temperature change most rapidly with depth?
#Question id: 2584
#Unit 2. Cellular Organization
The polymerization of pure G-actin in vitro proceeds in three phases.
|
Column I |
Column II |
|
A. nucleation phase |
i. G-actin monomers exchange with subunits at the filament ends, but there is no net change in the total length of filaments |
|
B. elongation phase |
ii. marked by a lag period in which G-actin subunits combine into an oligomer of two or three subunits |
|
C. steady-state phase |
iii. the short oligomer rapidly increases in length by the addition of actin monomers to both of its ends |
Which of the following represent correct match?
#Question id: 2515
#Unit 2. Cellular Organization
Which of the following cell types would be the best source of actin?
#Question id: 1370
#Unit 4. Cell Communication and Cell Signaling
H. V. Wilson worked with sponges to gain some insight into exactly what was responsible for holding adjacent cells together. He exposed two species of differently pigmented sponges to a chemical that disrupted intercellular junctions, and the cells of the sponges dissociated. Wilson then mixed the cells of the two species and removed the chemical that caused the cells to dissociate. Wilson found that the sponges reassembled into two separate species. The cells from one species did not interact or form associations with the cells of the other species.
How do you explain the results of Wilson's experiments?