Practice Questions

TLS Online TPP Program

#Question id: 7200

Following statements are regarding to Reaction-diffusion mechanism for proximal-distal limb specification. Which of the following statement is incorrect?

#Unit 5. Developmental Biology

In the inhibitory domain immediately outside the AER, cells are kept dividing by FGFs and Wnts and are prevented from forming cartilage.
In the active domain, each cell secretes but can not respond to activating paracrine factors of the TGF-β family (TGF-β, BMPs, activin) and cell adhesion factors such as galectin-1. These factors stimulate their own synthesis as well as that of the extracellular matrix and cell adhesion proteins that promote aggregation.
The activating cells also stimulate the synthesis of diffusible inhibitors of aggregation (including Noggin and galectin-8), preventing cell adhesion in neighboring regions.
A third domain, the “frozen zone” well beyond the influence of the AER, contains the formed cartilage primordia of the skeleton at proximal regions of the developing limb.

More Questions

TLS Online TPP Program

#Question id: 3554

#Unit 8. Inheritance Biology

The diploid cell with 6 pairs of chromosomes can divide. How many possible different combinations of maternal and paternal chromosomes in metaphase?

TLS Online TPP Program

#Question id: 11243

#Unit 10. Ecological Principles

Which of the following would be a hermaphrodite?

TLS Online TPP Program

#Question id: 11643

#Unit 7. System Physiology – Animal

Rapid changes to skin color in many vertebrates is under the control of ________.

TLS Online TPP Program

#Question id: 10806

#Unit 6. System Physiology – Plant

HCN is a fast-acting toxin that inhibits

TLS Online TPP Program

#Question id: 12100

#Unit 10. Ecological Principles

Prairie dogs once covered the expanses of the Great Plains. Their grazing made the grass more nutritious for the huge herds of bison, and a variety of snakes, raptors, and mammals preyed on the rodents. In fact, the black- footed ferret (now endangered) specialized in prairie dog predation. Today, growing housing and agricultural developments have covered many prairie dog towns. Which of the following statements about prairie dogs is true?