The horizontal axis of the cladogram depicted below is a timeline that extends from 100,000 years ago to the present; the vertical axis represents nothing in particular. The labeled branch points on the tree (V-Z) represent various common ancestors. Let's say that only since 50,000 years ago has there been enough variation between the lineages depicted here to separate them into distinct species, and only the tips of the lineages on this tree represent distinct species.

 In Darwin's tree of life, each fork in the tree represents ________.

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#Question id: 1232

#Unit 1. Molecules and their Interaction Relevant to Biology

Which of the following mutations might confer a competitive advantage to an athlete by raising his or her hematocrit?

a. excess production of erythropoietin                       

b. decreased production of erythropoietin

c. EpoR that cannot bind STAT5                  

d. EpoR that cannot bind SHP1

e. EpoR that cannot bind JAK2

TLS Online TPP Program

#Question id: 27070

#Unit 1. Molecules and their Interaction Relevant to Biology

Which of the following statements is correct regarding the stereochemistry of Thr, Ile 

1. Thr, Ile is special case because of two chiral center exist in L-Ile in 2R,3S and L-Thr in 2R,3S configuration 

2. Thr, Ile is special case because of two chiral center exist in D-Ile in 2R,3S and D-Thr in 2R,3S configuration 

3. Thr, Ile is special case because of two chiral center exist in L–Ile in 2S,3R and L–Thr in 2S,3R 

4. Thr, Ile is special case because of two chiral center exist in D–Ile in 2S,3R and D–Thr in 2S,3R

TLS Online TPP Program

#Question id: 27069

#Unit 1. Molecules and their Interaction Relevant to Biology

Choose the correct option regarding the stereochemistry of given compound 

TLS Online TPP Program

#Question id: 27068

#Unit 1. Molecules and their Interaction Relevant to Biology

Isoleucine and Threonine have two chiral carbons so exists in multiple RS configuration, choose the correct option regarding the given fig.

1. a is D-threonine is (2S, 3S) threonine

2. b is L-threonine is (2R,3S) threonine

3. a is L-threonine is (2S, 3R) threonine

4. b is D-threonine is (2R,3S) threonine

TLS Online TPP Program

#Question id: 27067

#Unit 1. Molecules and their Interaction Relevant to Biology

Choose the correct statement regarding the stereochemistry of amino acid

1. 16 amino acid except (Thr, Ile, Cys, Gly) L Fischer projection is equal to S and D is equal to R configuration 

2. Thr, Ile is special case because of two chiral center exist in L – Ile/Thr – 2S,3R and D-Ile/Thr–2R,3S configuration  

3. Cys exiest in L- Cys – R & D- Cys – S configuration 

4. Gly is optically inactive 

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#Question id: 744

#Unit 1. Molecules and their Interaction Relevant to Biology

In a DNA molecule, deoxyribonucleotides are joined into a polymer by the covalent linkage of a phosphate group. The covalent link termed as: