Answer:
Evolution is a change in the inheritable phenotypic characters within a population occurs through successive generations.
Explanation:
Evolution is a change in inheritable characters of population during a period of time by means of natural selection. These changes in phenotypic characters brings the formation of new species. Darwin's theory consists of three categories,individuals within a group are variables, variations are inheritable,all individuals with variables survive.
According to Darwin's theory states that survival is based on selective mode like particular phenotypic characteristics or behavior given to some individuals who are able to survive in a particular environment.
Answer:
Similarities: both are chemical messengers, both can have (but don't necessarily have) similar structures (made from amino acids), both can be produced by the central nervous system (hypothalamus produces some hormones), certain molecules can act as both hormones and neurotransmitters (example: norepinephrine).
Differences: neurotransmitters are released by neurons across a synaptic gap, have very short distances to travel, and act very quickly on the neighboring cell. Hormones are released by glands and often have to travel longer distances, which means that they are slower-acting. Also, hormones are typically used for regulation (negative feedback) while neurotransmitters are used for stimulation of a neighboring cell.
Explanation:
The naturally occurring solid mixture of one or more minerals and organic matter is known as a Rock.
A rock is a naturally occurring substances that is a solid mixture of one or more minerals together with organic matter.
<h2>Further Explanation;</h2>
- Rocks are classified based on the chemical composition, texture and the way they are formed. One type of rock may change from one form to another through a rock cycle.
- Rock cycle is the process through each various rocks change from one form to another, normally an interchange between the three major types of rocks.
There are three major classification of rocks:
<h3>Sedimentary rocks </h3>
- Sedimentary rocks are types of rocks that are formed through accumulation of sediments at low temperatures in tectonic layers and sinks. These sediments includes; pebbles, shells, sand and other material fragments.
- The sediments accumulates in layers and then harden into rocks over a period of time.
- Examples of sedimentary rocks include; limestone and conglomerate
<h3>Metamorphic rocks</h3>
- These are types of rocks that are formed as a result of changes that occurs due to intense heat and pressure under the surface of the earth. They result from action of heat and pressure on other rocks that pre-existed.
- These types of rocks are characterized by shiny crystals, ribbon-like layers among other features.
- Examples of metamorphic rocks are marble and gneiss
<h3>Igneous rocks </h3>
- These are types of rocks that are formed as a result hardening and cooling of magma from volcanic eruptions. Magma may cool inside the earth or when on the surface of the earth as a result of volcanic eruptions. The lava from this eruptions cools and hardens to form metamorphic rocks.
- Igneous rocks are glass-like and shiny with no crystals. They may also have tiny spaces and holes due to gas bubbles trapped during the cooling process.
- Examples of igneous rocks include obsidian and basalt.
- The three types of rocks may be further classified in terms of chemical composition, texture and formation.
Key words: Rocks, types of rocks, chemical composition
<h3>Learn more about;</h3>
- Rocks and rock types; https://brainly.in/question/5987245
- sedimentary rocks; https://brainly.in/question/3259075
- igneous rocks; https://brainly.in/question/272012
- metamorphic rocks; https://brainly.in/question/1206219
Level; High school
Subject: Geography
Topic: Rocks
sub-topic: classification of rocks
<span>Only one sperm normally fuses
with an egg because if more than one sperm fuses, through a process
called polyspermy, development of the zygote usually stops.
</span>
<span>Fertilization of one egg by
two sperm is possible, but the resulting zygote is almost never viable
because such a zygote would have three sets of chromosomes instead of
the normal two. This condition, called triploidy, is usually
incompatible with life. Those rare triploid infants that do survive to
term have severe and multiple birth defects and rarely live more than a
few days. </span>
