TLS Online TPP Program

#Question id: 9265


To apply parsimony to constructing a phylogenetic tree,

#9. Diversity of Life Forms
  1. choose the tree that assumes all evolutionary changes are equally probable.
  2. choose the tree in which the branch points are based on as many shared derived characters as possible.
  3. choose the tree that represents the fewest evolutionary changes, in either DNA sequences or morphology.
  4. choose the tree with the fewest branch points.
More Questions
TLS Online TPP Program

#Question id: 383

#1. Molecules and their Interaction Relevant to Biology

Three buffers are made by combining a 1 M solution of acetic acid with a 1 M solution of sodium acetate in the ratios shown below

1 M acetic acid              

1 M sodium acetate  

Buffer 1: 10 mL

 90 mL

Buffer 2: 50 mL

50 mL

Buffer 3: 90 mL

10 mL

 Which of these statements is true of the resulting buffers?

TLS Online TPP Program

#Question id: 384

#1. Molecules and their Interaction Relevant to Biology

A solution was prepared by dissolving 0.02 moles of acetic acid (HOAc; pKa = 4.8) in water to give 1 liter of solution. What is the pH? To this solution was then added 0.008 moles of concentrated sodium hydroxide (NaOH). What is the new pH? (In this problem, you may ignore changes in volume due to the addition of NaOH).

TLS Online TPP Program

#Question id: 386

#1. Molecules and their Interaction Relevant to Biology

Which of the following properties of water does not contribute to the fitness of the aqueous environment for living organisms?

TLS Online TPP Program

#Question id: 387

#1. Molecules and their Interaction Relevant to Biology

For a weak acid with a pKa of 6.0, What would be the ratio of acid to salt at pH 5.

TLS Online TPP Program

#Question id: 389

#1. Molecules and their Interaction Relevant to Biology

A weak acid HA has a pKa of 5.0.  If 1.0 mol of this acid and 0.1 mol of NaOH were dissolved in one liter of water, what would the final pH be?

TLS Online TPP Program

#Question id: 390

#1. Molecules and their Interaction Relevant to Biology

What are the properties arising due to varying concentrations of solute in a given solvent, irrespective of the nature of solute with respect to the solvent?