Ques: Answer the following question given this paragraph: Almost all fungi have a single common ancestor. The earliest fungi may have evolved about 600 million years ago. Fungi colonized land at least 460 million years ago. By 250 million years ago, they may have been the dominant life forms on Earth. Q: Evolving from a single common ancestor, what group of organisms was perhaps the dominant life form on earth 250 million years ago? Choices: - acids - atoms - proteins - fungi A:
Ans: fungi

Ques: Answer the following question given this paragraph: Sympatric speciation While the logic and mechanisms of allopatric speciation are relatively easy to grasp (we hope), there is a second type of speciation, known as sympatric speciation, which was originally more controversial. It occurs when a single population of organisms splits into two reproductively isolated communities within the same physical region. How could this possibly occur? What stop (or inhibits) the distinct sub-populations from inbreeding and reversing the effects of selection and nascent speciation? Recently a number of plausible mechanisms have been identified. One involves host selection.143 In host selection, animals (such as insects) that feed off specific hosts may find themselves reproducing in distinct zones associated with their hosts. For example, organisms that prefer blueberries will mate in a different place, time of day, or time of year than those that prefer raspberries. There are blueberry- and raspberry-specific niches. Through a process of disruptive selection (see above), organisms that live primarily on a particular plant (or part of a plant) can be subject to different selective pressures, and reproductive isolation will enable the populations to more rapidly adapt. Mutations that reinforce an initial, perhaps weak, mating preference can lead reproductive isolation - this is a simple form of sexual selection (which we will discuss soon).144 One population has become two distinct, reproductively independent populations, one species has become two. Q: Sympatric type of what occurs when a single population of organisms splits into two reproductively isolated communities within the same physical region? Choices: - biodiversity - extraction - accumulation - speciation A:
Ans: speciation

Ques: Answer the following question given this paragraph: Mineralocorticoids Mineralocorticoids are hormones synthesized by the adrenal cortex that affect osmotic balance. Aldosterone is a mineralocorticoid that regulates sodium levels in the blood. Almost all of the sodium in the blood is reclaimed by the renal tubules under the influence of aldosterone. Because sodium is always reabsorbed by active transport and water follows sodium to maintain osmotic balance, aldosterone manages not only sodium levels but also the water levels in body fluids. In contrast, the aldosterone also stimulates potassium secretion concurrently with sodium reabsorption. In contrast, absence of aldosterone means that no sodium gets reabsorbed in the renal tubules and all of it gets excreted in the urine. In addition, the daily dietary potassium load is not secreted and the retention of K+ can cause a dangerous increase in plasma K+ concentration. Patients who have Addison's disease have a failing adrenal cortex and cannot produce aldosterone. They lose sodium in their urine constantly, and if the supply is not replenished, the consequences can be fatal. Q: Mineralocorticoids are hormones synthesized by the adrenal cortex that affect what balance, by regulating sodium and water levels? Choices: - blood pressure - homeostasis - equilibrium - osmotic A:
Ans: osmotic

Ques: Answer the following question given this paragraph: Nutrients the body needs in relatively small amounts are called micronutrients . They include vitamins and minerals. Vitamins are organic compounds that are needed by the body to function properly. Several vitamins are described in Table below . Vitamins play many roles in good health, ranging from maintaining good vision to helping blood clot. Vitamin B12 is produced by bacteria in the large intestine. Vitamin D is synthesized by the skin when it is exposed to UV light. Most other vitamins must be obtained from foods like those listed in Table below . Q: What is the term for nutrients the body needs in relatively small amounts, including vitamins and minerals? Choices: - minor nutrients - insignificant nutrients - trace nutrients - micronutrients A:
Ans:
micronutrients