Vacoule
Cell wall
Cytoplasm
<h3><u>Answer;</u></h3>
C.) The number of differences in a specific DNA sequence of two species is multiplied by a known mutation rate to determine the number of years of evolution that separate the two species.
<h3><u>Explanation</u>;</h3>
- Molecular clocks are used to date origin of species. They are based on the observation that random mutations accumulate in genes at a fairly constant rate
.
- Once a mutation rate is determined it can be used to establish dates of divergence of species.
- Molecular clocks can be used in putting a series of evolutionary events into chronological order, by comparing sequences from different species to determine when they last shared a common ancestor, in effect drawing the family tree.
Answer: zygote
Explanation: A zygote is a single cell created when the sperm and egg are combined.
Answer:
true
Explanation:
<em><u>Some water pollution is caused from “point sources” that is discrete locations, from which pollutants are discharged, e.g., a pipe, ditch, ship, or factory smokestack. Point sources originate in large and easy to trace facilities, hence are easier to control. In contrast, pollution from “nonpoint” sources is cumulative, arising from multiple inputs over larger areas, such as farms, city streets, and residential neighbourhoods. Hence, such sources are harder to precisely identify, and because of this uncertainty, nonpoint source pollution is harder to control than the point source.</u></em>
Synaptic cleft
- A gap between the neurons