Answer:
A cell is the smallest unit of a living thing.
Answer:
P wave
Explanation:
Electrocardiogram records the strength and timing of electrical activity in heart. As various regions of heart contract at different times and for different duration, the electrical activity is not constant and shows a series of rise and fall. There are three main components of ECG: P wave, QRS complex and T wave.
P wave indicates the beginning of electrical signal in the right atrium. The signal spreads in both right and left atria which leads to their contraction. As a result, blood is pumped into the ventricles and rest of the process occurs.
Answer:In the nucleus of each cell, the DNA molecule is packaged into thread-like structures called chromosomes. Each chromosome is made up of DNA tightly coiled many times around proteins called histones that support its structure.
Chromosomes are not visible in the cell’s nucleus—not even under a microscope—when the cell is not dividing. However, the DNA that makes up chromosomes becomes more tightly packed during cell division and is then visible under a microscope. Most of what researchers know about chromosomes was learned by observing chromosomes during cell division.
Each chromosome has a constriction point called the centromere, which divides the chromosome into two sections, or “arms.” The short arm of the chromosome is labeled the “p arm.” The long arm of the chromosome is labeled the “q arm.” The location of the centromere on each chromosome gives the chromosome its characteristic shape, and can be used to help describe the location of specific genes.
Answer:
The logistic population growth happens as the growth rate declines as the population exceeds the carrying power. The highest number of people in a community that the ecosystem can sustain is carrying capacity.
Explanation: