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TLS Online TPP Program

#Question id: 23141

Resolution of a light microscope is 0.42nm at 300 wavelength of light. If the specimen is viewed under oil what is the refractive index?

#Unit 13. Methods in Biology

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TLS Online TPP Program

#Question id: 15150

#Unit 8. Inheritance Biology

In this problem we will explore some of the many ways that mutations in two different genes can interact to produce different Mendelian ratios. Consider a hypothetical insect species that has red eyes. Imagine mutations in two different unlinked genes that can, in certain combinations, block the formation of red eye pigment yielding mutants with white eyes. In principle, there are two different possible arrangements for two biochemical steps responsible for the formation of red eye pigment. The two genes might act in series such that a mutation in either gene would block the formation of red pigment. Alternatively, the two genes could act in parallel such that mutations in both genes would be required to block the formation of red pigment.

Further complexity arises from the possibility that mutations in either gene that lead to a block in enzymatic activity could be either dominant or recessive. If the crosses is made between a wild type insect with red eyes and a true breeding white eyed strain with mutations in both genes. Such considerations yield the Pathways in series with recessive mutations in both genes, the F1 progeny shows will have red eye, what is the expected phenotypic ratio of red to white eyed insects in the F2.

TLS Online TPP Program

#Question id: 12991

#Unit 1. Molecules and their Interaction Relevant to Biology

Choose the correct statements

a. Secondary structures are stabilized by hydrogen bonds.

b. Hydrogen bond always formed between non bonded atoms.

c. the folded length of an amino acid in α-helix reduced almost 3 times than linear structure.

d. Only dihedral angle changes during the formation of secondary structure while bond length remains unchanged

TLS Online TPP Program

#Question id: 31133

#Unit 2. Cellular Organization

The main glucose transporter in the cells of skeletal muscle, cardiac muscle, and adipose tissue, called:

TLS Online TPP Program

#Question id: 9619

#Unit 9. Diversity of Life Forms

A common ancestor for both species C and E could be at position number

TLS Online TPP Program

#Question id: 1253

#Unit 4. Cell Communication and Cell Signaling

Following statements are regarding to the wnt signalling.

A. Wnt proteins interact with several cell-surface proteins and activate multiple downstream signal transduction pathways. The principal signaling receptor for Wnt proteins is Frizzled (Fz), which contains seven transmembrane α helices.

B. The palmitate attached to the Wnt protein binds to a specific site on the Fz intracellular domain and stabilizes the Wnt-Fz complex.

C. “canonical” Wnt signaling pathway uses a second transmembrane protein, LRP, that associates with Frizzled in a Wnt signal– dependent manner.

D. In the resting state, two kinases in the complex, casein kinase 1 (CK1) and GSK3, sequentially phosphorylate β-catenin on multiple tyrosine residues.

Which of the following statements are correct?