Biology Test - 59

Activities of phosphofructokinase is promoted by the accumulation of AMP.

Phosphofructokinase from yeast is effectively activated by AMP and fructose- \(2,6\) bisphosphate by increasing the affinity of the enzyme to fructose-\(6\)-phosphate and the maximum activity toward this substrate. The enzyme is promote by AMP and fructose-\(2, 6\) bisphosphate both at high and at low concentrations of ATP.

AMP (Adenosine monophosphate) effector is produced in increasing amounts from ATP during exercise. It allosterically stimulates PFK-\(1\) in muscle, increasing glycolysis to restore the ATP concentrations to normal.

The rate of total capture of energy or the rate of the total production of organic material is gross primary productivity while the balance or biomass remaining after meeting the cost of respiration of producers is net primary productivity.

So, Gross production (GP) has the highest value in the grassland ecosystem.

DNA has a double-stranded structure that is helical in orientation.In a DNA strand, the nucleotides are arranged in a manner that adenine is always paired with thymine and cytosine is always paired with guanine. Adenine and thymine are joined by two hydrogen bonds and guanine and cytosine are always joined by three hydrogen bonds.The Chargaff’s rule of base pairs states that the base pairs are present in a one to one ratio in a DNA segment. According to this, if there are \(120\) adenine, there have to be \(120\) thymines also present. If there are \(120\) cytosines, there should be \(120\) guanines also present. So there will be \(480\) nucleotides present in the given segment.

In eukaryotes the complete oxidation of a molecule of glucose results in the net gain of\(38\) molecules of ATP.

Complete oxidation of glucose occurs through three steps :

• Glycolysis
• Krebs cycle
• Terminal oxidation

During glycolysis glucose changes to pyruvic acid gaining total energy as \(2\) ATP molecules and \(2\) molecules of \(NADH _{2}\) then later on in Krebs cycle \(30\) ATP molecules and \(2 FADH _{2}\) are produced. One \(NADH _{2}\) produces \(3\) ATP molecules while one \(FADH _{2}\) produces two ATP molecules. Therefore in complete oxidation of one molecule of glucose, a total of \(38\) ATP's are gained.

Protein is the component of food that helps the human body fight infections. Proteins are vitamins and minerals that fight germs. Protein is important for building and repairing body tissues and fighting viral and bacterial infections. Immune system powerhouses such as antibodies and immune system cells depend on proteins. Too little protein in the diet can cause symptoms of weakness, fatigue, apathy and poor immunity.

The Dominions were autonomous communities within the British Empire that were “equal in status” but had an “allegiance to the Crown''.
The Simon commission had promised ‘Dominion Status’ for India in 1929, but the Government of India Act did not confer it.
The Act did not even mention the Dominion status. 

Unmyelinated nerve fiber isenclosed by a Schwann cell that does not form a myelin sheath.

The myelinated nerve fibres contain a myelin sheath surrounding the axons of nerve cells. Unmyelinated nerve fibre is not enclosed by a Schwann cell and hence does not form a myelin sheath around the axon.

Pusa Komal is a crop variety of cowpea. It is resistant to bacterial blight.

All cultivated cowpeas are found within the universally accepted V. unguiculata subspecies unguiculata classification, which is then commonly divided into four cultivar groups: unguiculata, biflora, sesquipedalis, and textiles.

The paradox between the work of Darwin and that of Pasteur was Pasteur’s work posed a challenge to ideas about how life ultimately began.

Pasteur’s publication of his experiments that disproved spontaneous generation came in the same year as Darwin’s Origin of Species. This made for paradox. Darwin’s theory of natural selection explained how complex life forms could arise from simpler organisms. But when scientists carried this idea back to how life started in the first place, the only explanation they had was disproved by Pasteur.

Ovaries are the ova produced and mature from infancy in the female reproductive system.

Ovaries:

• The ova (eggs) are producedin the ovaries. They arematured from folliclesthat arestoredin theovaries of the woman.
• The eggis latertransferred to the uterus through the fallopian tube for fertilization.

Fallopian Tube:

• The Fallopian Tube isabout 10-12 cm long and extends from the periphery of each ovary to the uterus.

Uterus:

• The uterus issingleand it is alsocalled the womb.
• Theshapeof theuterus is like an inverted pear.
• It issupportedbyligaments attached to the pelvic wall.

Labia:

• The Labia are theouter portion of the vulva, there are two pairs of labia.
• One beinglabia majora (larger)and thelabia minor (smaller)theyprotect the entrance to the reproductivesystem.