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TLS Online TPP Program

#Question id: 10205

The xanthophyll cycle, which comprises the three carotenoids violaxanthin, antheraxanthin, and zeaxanthin, establishes an ability to dissipate excess light energy in the leaf, Under high light the conversion of the carotenoids such as

#Unit 6. System Physiology – Plant
  1. antheraxanthin is converted to violaxanthin and then to zeaxanthin
  2. violaxanthin is converted to zeaxanthin as well as in antheraxanthin
  3. violaxanthin is converted to antheraxanthin and then to zeaxanthin
  4. violaxanthin and zeaxanthin both will be converted into antheraxanthin
More Questions
TLS Online TPP Program

#Question id: 14990

#Unit 4. Cell Communication and Cell Signaling

Which smaller group of cells that crawl slowly along blood vessels, and that also  migrate into tissues in response to infection can differentiate into specific tissue macrophages ?
TLS Online TPP Program

#Question id: 5674

#Unit 5. Developmental Biology

Following statements are regarding to the mechanism of migration of pollen tube.

A. The embryo sac is the product of three mitotic divisions of the diploid megaspore; it comprises seven cells and eight haploid nuclei.

B. The two polar nuclei in the central cell will fuse with the second sperm nucleus and produce the endosperm that will nourish the egg. The other six cells, including the egg, contain one haploid nucleus each.

C. After compatible pollen germinates, the pollen tube grows toward the micropyle.

D. The three cells from the pollen are connected to one another at the tip of the tube, and waves of sodium ions play a key role in the growth of the tube.

Which of the following combinations are correct?
TLS Online TPP Program

#Question id: 28772

#Unit 2. Cellular Organization

M6P residues are generated in the cis-Golgi by which of the following Golgi-resident enzymes?
a) N-acetylglucosamine (GlcNAc) phosphotransferase
b) ornithine transcarbamylase 
c) Phosphodiesterase
d) Catalases
TLS Online TPP Program

#Question id: 12988

#Unit 10. Ecological Principles

Population ecologists follow the fate of same-age cohorts to
TLS Online TPP Program

#Question id: 12429

#Unit 10. Ecological Principles

Flycatcher birds that migrate from Africa to Europe feed their nestlings mostly with moth caterpillars. The data presented show the mean dates of egg laying, hatching, and fledging of flycatcher young, and the 1980 and 2000 peak mass of caterpillars.


Which of the following organisms is incorrectly paired with its trophic level?