Answer:
-The moon orbits the Earth
-The Earth orbits the Sun
-The Moon orbits the Earth but not the sun
An atom will usually form either an ionic bond or covalent bond with another atom but not both.
Ionic bonds are the kind of bonds that result when one atom transfers or gives up electrons and another atom receives them and adds them to its own energy shells.
An example is sodium metal and chlorine gas. Sodium gives up two of its electrons and Chlorine receives them and the two elements form an ionic bond to create sodium chloride, a new compound.
Covalent bonds are the kind of bonds formed when two atoms decide to share electrons. No atom gives up any electrons and neither does the other atom receive any. An example is water. An oxygen atom shares two of its electrons with two hydrogen atoms to form a molecule of water (H2O).
Answer:
Repolarization
Explanation:
Repolarization refers to the phase during which the resting potential is restored after depolarization. This means that the inside of the axon membrane becomes negative again compared to the outside.
Repolarization is obtained by the functioning of K+ ion channels. The opening of K+ ion channels allows the K+ to move outside of the axon. Movement of positively charged ion (K+) outside of axon makes the inside negative again and the resting potential is restored.
Answer;
C) A positive feedback loop.
Explanation;
-Biological systems operate on a mechanism of inputs and outputs, each caused by and causing a certain event. A feedback loop is a biological occurrence in which the output of a system amplifies the system (positive feedback) or inhibits the system (negative feedback)
-Oxytocin is controlled by a positive feedback mechanism where release of the hormone causes an action which stimulates more of its own release. When contraction of the uterus starts, for example, oxytocin is released which stimulates more contractions and more oxytocin to be released.
Answer:
The correct answer is A. pollen.
Explanation:
Pollen is a very efficient way to colonize and reach further. It's believed that this adaptation is the main reason why land plants could colonize so many environments. The fact that pollen is little and easily transported also was very important.
