The temperature of the body is regulated almost entirely by nervous feedback mechanisms, and almost all these mechanisms operate through temperature regulating centers located in the hypothalamus. Following statements are as follows:

A. The anterior hypothalamic-preoptic area contains large numbers of heat-sensitive neurons, as well as about one third as many cold-sensitive neurons. These neurons are believed to function as temperature sensors for controlling body temperature.

B. The heat-sensitive neurons increase their firing rate 2- to 10-fold in response to a 10°C increase in body temperature. 

C. The cold-sensitive neurons, by contrast, increase their firing rate when the body temperature increases.

D. Anterior hypothalamus integrates the central and peripheral temperature sensory signals.

Which of the following combination is correct?

TLS Online TPP Program

#Question id: 13193

#Unit 1. Molecules and their Interaction Relevant to Biology

Data, collected from DNAs of a great many different species, led Chargaff to the following conclusions:

A. The base composition of DNA generally varies from one species to another.

B. DNA specimens isolated from different tissues of the same species have the different base composition.

C. The base composition of DNA in a given species changes with an organism’s age, nutritional state, or changing environment.

D. In all cellular DNAs, the sum of the purine residues equals the sum of the pyrimidine residues.

Which of the above statements are INCORRECT regarding Chargaff’s rule?

TLS Online TPP Program

#Question id: 10476

#Unit 1. Molecules and their Interaction Relevant to Biology

Following statements are regarding to gangliosides.

A. They are ceramides with attached oligosaccharides that include at least one sialic acid residue.

B. They are ceramides with attached oligosaccharides that include at least one phasphatidic acid residue.

C. Sialic acid gives gangliosides the negative charge at pH 7 that distinguishes them from globosides.

D. Gangliosides are primarily components of cell-surface membranes and constitute a significant fraction (6%) of brain lipids.

Which of the following combination is correct?

TLS Online TPP Program

#Question id: 10475

#Unit 1. Molecules and their Interaction Relevant to Biology

During the formation of a blood plasma protein The aromatic ring of vitamin K undergoes:

TLS Online TPP Program

#Question id: 10474

#Unit 1. Molecules and their Interaction Relevant to Biology

Lipids differ from other large biological molecules in that they

TLS Online TPP Program

#Question id: 10473

#Unit 1. Molecules and their Interaction Relevant to Biology

Cleavage of beta-carotene by BCMO1 yields two molecules of :

TLS Online TPP Program

#Question id: 10321

#Unit 1. Molecules and their Interaction Relevant to Biology

The human blood groups (O, A, B) are determined in part by the oligosaccharide head groups of these glycosphingolipids. Which of the following is correct?