Answer:
Groundwater is transported through aquifers because of two main reasons: gravity and pressure. In unconfined aquifers, which we concentrate on because they are more likely to be contaminated, water always flows from high points to low points because of gravity.
Explanation:
the answer is moon. the name tells you what you can't see. since in a solar eclipse you can't see the sun that means that the moon is in between us on earth and the sun. which is why we can't see it
The total volume of the gas-exchanging region in the lung is called alveolar volume.
The alveolus is an air sack-like organ in the end of the respiratory airway. The alveolus is the site where gas-exchanging happens, so only air inside alveolus that will undergo actual exchange. Air in bronchus or trachea wouldn't do exchange
Answer: Substances that are protein based cannot cross the lipid cell membrane, but can exert their effect by binding to the proteins based receptors present on the lipid bilayer.
Explanation:
Hormones such as calcitonin , Parathyroid hormone and pituatry horomones are proteins and water soluble.They cannot cross lipid bilayer but can bind to ligand binding protein receptors.
These receptors are protein macromolecules that are specific in nature for specific hormones.
After binding to the receptors, these hormone-recpetor complexes activate second messengers and regulate the downstream effects.
Answer:
What was the first hominid ancestor?
The first early hominid from Africa, the Taung child, as it was known, was a juvenile member of Australopithecus africanus, a species that lived one million to two million years ago, though at the time skeptical scientists said the chimpanzee-size braincase was too small for a hominid.