Measuring photosynthesis via the production of oxygen. Oxygen can be measured by counting bubbles evolved from pondweed, or by using the Audus apparatus to measure the amount of gas evolved over a period of time.
Answer:
A) Proportion of females with the trait is less than 8%
B) Proportion of females that would be carriers is greater than 8%
Explanation:
Only the 8% male sufferers can give their diseased X-chromosome for the female XX to be formed. hence, the proportion of the female carriers is most likely greater than 8%
On the other hand, the proportion of female sufferers will be definitely less than 8%, for 92% of the remaining male population are neither carriers nor sufferers; and the 8% male sufferers are strictly needed to give the disease X-chromosome for a female to have the trait XX.
Answer:
humans had more developed 'social' brains than Neanderthals, which enabled us to colonize new habitats and adapt to climate fluctuations
Explanation:
A more developed brain is considered to be an adaptive advantage that enabled early humans to leave Africa and colonize new habitats. Modern humans are able to adjust to new environments, situations, and socialize with other humans because the brain is a social organ. Although Neanderthals were able to occupy an important area of Europe, H. sapiens could colonize faraway lands, migrating into tropical forests, deserts, and glacial lands (colder areas than those colonized by Neanderthals). These early humans formed social groups which enabled them to find food more easily, thus greatly increasing their chances for survival.
Lithium, Boron, Florine, Silicon, Vanadium, Chromium, Manganese, Zinc, Copper, Nickel, Cobalt, Iron, Arsenic (yes, but in very small amounts), Selenium, Bromine, Strontium, Molybdenum, and Iodine.
Calcium levels in the body are maintained by hormones. If the blood calcium level rises above a set point, calcitonin is secreted by the thyroid gland and sets into motion responses to lower the blood calcium back to the set point. If the blood calcium level falls below a set point, the parathyroid gland secretes parathyroid hormone that sets into motion responses to raise the blood calcium. These homeostatic responses are examples of:
a. positive feedback
b. effectors
c. sensors
d. negative feedback
Answer:
d. negative feedback
Explanation:
Negative feedback responses are the ones that counteract the change. Any alterations in the internal body conditions such as blood calcium levels are sensed by receptors. The information is sent to the brain which in turn commands the effectors such as endocrine glands to secrete the required hormones to restore the normal conditions. Here, changes in the calcium levels are counteracted by the secretion of calcitonin and parathyroid hormones and the calcium is maintained within a narrow range. This represents negative feedback.