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TLS Online TPP Program

#Question id: 5004

Pax-6 usually causes the production of a type of light-receptor pigments. In vertebrate eyes, though, a different gene (the rh gene family) is responsible for the light-receptor pigments of the retina. The rh gene, like Pax-6, is ancient. In the marine ragworm, for example, the rh gene causes production of c-opsin, which helps regulate the wormʹs biological clock. Which of these most likely accounts for vertebrate vision?

#Unit 11. Evolution and Behavior

  1. The Pax-6 gene mutated to become the rh gene among early mammals.

  2. During vertebrate evolution, the rh gene for biological clock opsin was co-opted as a gene for visual receptor pigments.

  3. In animals more ancient than ragworms, the rh gene(s) coded for visual receptor pigments; in lineages more recent than ragworms, rh has flip-flopped several times between producing biological clock opsins and visual receptor pigments.

  4. Pax-6 was lost from the mammalian genome, and replaced by the rh gene much later.

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TLS Online TPP Program

#Question id: 4890

#Unit 8. Inheritance Biology

A strain of Neurospora crassa, unable to synthesize the vitamin thiamine (t), is crossed with a strain that cannot synthesize the amino acid arginine (a). What information can be obtained from the resultant frequencies of ascospore patterns?

 A) The two loci (a) and (t) are independent assortment of each other

B) Both genes are closely linked to their respective centromeres.

C) no crossovers occurred between either gene and its centromere.

D) These two gene may reside on different chromosomes.
TLS Online TPP Program

#Question id: 12640

#Unit 6. System Physiology – Plant

Plant species produce a which type of  defensive proteins that bind to carbohydrates or carbohydrate-containing proteins. After being ingested by an herbivore, that bind to the epithelial cells lining the digestive tract and interfere with nutrient absorption
TLS Online TPP Program

#Question id: 12306

#Unit 7. System Physiology – Animal

 Which of the following is true of the tubular fluid that passes through the lumen of the early distal tubule in the region of the macula densa?
TLS Online TPP Program

#Question id: 13122

#Unit 2. Cellular Organization

Choose the incorrect?
1- COPI vesicles transport proteins from the rough ER to the cis -Golgi; COPII vesicles transport proteins in the reverse s Direction.
2- The KDEL receptor binds more tightly to its ligand ar low pH, and it is thought that the receptor is able to bind KDEL peptides in the cis-Golgi but to release these peptides in the ER because the pH of the Golgi is slightly lower than that of the ER.
3- The KDEL sorting signal is recognized and bound by the KDEL receptor, a transmembrane protein found primarily on small transport vesicles shuttling between the ER and the cis -Golgi and on the cis-Golgi reticulum.
TLS Online TPP Program

#Question id: 23478

#General Aptitude

Such a Network which helps in communicating regional, national and global information’s through large institutions is called