True, This is because they they reproduced itself by spores called Sori so therefore they do grow underground stem
Answer: Natural selection is one of the forces of evolution and the enviroment where the species lives is the selection agent. For example, suppose a mosquitoes population in a environment free from insecticides, in this environment there's a high frequency of non-resistant mosquitoes because the environment is not exerting any pressure on the resistence trait. But when the environment changes and we use a insecticide upon the mosquitoes population, the populations changes because the non-resistant ones die but those resistant survive and beggin to reproduce more effectively. That's natural selection, differences in survival and reproduction between individuals with different phenotypes (traits) and this differences depend of environmental changes.
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.
1.b
2. a
3.c
4. d
5. e
6. j
7. h
8. i
9. f
10 g
