Biology Answers

Blood being carried towards the heart is always oxygen-depleted.

True

False

What is the key difference between veins and arteries?

A. Veins carry oxygen-rich blood; arteries carry oxygen-depleted blood

B. Veins carry blood towards the heart; arteries carry blood away from the heart

C. Veins carry oxygen-depleted blood; arteries carry oxygen-rich blood

D. Veins carry blood away from the heart; arteries carry blood towards the heart

E. None of these choices is correct

Is it C?

In the sense-integrate-act loop, the brain is always where signals are integrated.

True

False

When the brain integrates signals from different sensory systems, all these signals receive equal weight in determining the actions & forming memories.

When the brain integrates signals from different sensory systems, all these signals receive equal weight in determining the actions & forming memories.

True

False

How is mean arterial pressure (MAP) calculated and why is it useful? ( short answer please)

What is the isoelectric point of each of the following peptides?

1. His-Ala-Tyr

2. Ala-Lys-His-Ala

3. Consider the system, G + H <===> I + J at 25 °C. What is the total free energy change of this system if the total enthalpy change (heat content change) of the system is 2637 J/mol and the total entropy change is -0.78 kJ/mol.K ?

Is the system described in problem #5 endothermic or exothermic? _______________________ 

Is the system described in problem #1 endergonic or exergonic? _________________________

4. Consider the two systems shown below. These systems are coupled such that compound X carrying a phosphate group (X-P) transfers the phosphate to compound Y forming Y-P (that is Y carrying a phosphate group). (Pi represents unbound phosphate.)

Reaction 1: X-P + H2O <===> X + Pi ∆G = -43.0 kJ/mol Reaction 2: Y + Pi <===> Y-P + H2O ∆G = +29.4 kJ/mol

What is the ∆G for the combined system? ___________________________________________ 

Which reaction (system) is driving the other to proceed? _________________________________

1. Consider the system, A + B <===> C + D at 25 °C. What is the total free energy change of this system if the total enthalpy change of the system is -3145 J/mol.K and the total entropy change is +0.47 kJ/mol.K ?

Is the system described in problem #1 endothermic or exothermic?

______________________ 

Is the system described in problem #1 endergonic or exergonic? _________________________

2. If the total free energy change of the system X + Y <===> X-Y at 37 °C is +2618.2 J/mol and the total entropy change is -173.5 J/mol.K , what is the total enthalpy change?

Is the system described in problem #3 endothermic or exothermic? _________________________ 

Is the system described in problem #3 endergonic or exergonic? _________________________

Use diagrams and equations to distinguish between the three general types of allometric relationships.

Explain how gas secretion into the swimbladders of bony fish is possible.