Biology Answers

The net productivity of the different trophic levels in the food chain are as follows:

Grass: 13,883kJ m-2 yr-1
Arctic hare: 2345 m-2 yr-1
Arctic fox: 137 m-2 yr-1

Explain why the net productivity of the Arctic hare is less than the net primary productivity of the grass.

In a vegetable section of a particular supermarket, Aling Nena noticed that every 10 minutes the fresh produce were sprinkled with water by a sales clerk. Can you explain the concept of tonicity in this situation? What is the importance of the discovery of aquaporin in humans?

1. Mang Nestor has a poultry farm. Every morning, he collects eggs and sell it in the market. Those are unsold, he made it as salted egg. In doing this, the eggs were soaked in a container having one liter of water with 1 kg dissolved salt solution. After 18 days, Mang Nestor collected salted eggs for his everyday consumption. What transport mechanism/concepts can be applied in salted egg making? Explain

How do communication signals participate in reproductive isolation? Give one example of a signal that is species-specific. Why are some signals individually specific?

In birds, how does the amount of parental care required by the offspring affect the evolution of a species’ mating system?

1. Consider a liver cell carrying out the oxidation of glucose under aerobic conditions. Suppose that we added a very potent and specific inhibitor of the mitochondrial ATP synthase, completely inhibiting this enzyme. Indicate whether each of the following statements about the effect of this inhibitor is true or false; explain in a sentence or two why. [10 pts]

____ (A) ATP production in the cell will quickly drop to zero.





____ (B) The rate of glucose consumption by this cell will decrease sharply.





____ (C) The rate of oxygen consumption will increase.





____ (D) The citric acid cycle will speed up to compensate.

In humans, diabetes is a sex-linked recessive trait. If a homozygous normal woman and a man, whose mother is a diabetic, have children, what will be the phenotypes and genotypes of their children?

A reaction mixture includes hexokinase, glucose isomerase and 0.0001 mol / l glucose. Hexokinase (KM value = 10-5 mol / l) converts glucose to glucose-6-phosphate, glucose isomerase (KM value = 3.3 x 10-3 mol / l) to fructose. Which main product am I expecting?

How does DNA create parts of an organism?

Using the data below, create a line graph that shows change in solute concentrations (mOsm/l) as you move through the nephron. You may draw this graph on a piece of paper and attach as a photo. Ensure all axes are labelled and data points are clearly included.

Kidney structure

Osmolarity in milliosmoles per litre (mOsm/l)

Glomerulus

300

Proximal Convoluted Tubule

300

Descending Loop of Henle

800

Bottom of Loop of Henle

1200

Ascending Loop of Henle

600

Top of Loop of Henle

100

Distal Convoluted Tubule

300

Collecting Duct

1200