Answer:
Mature pollen grains contain two cells: a generative cell and a pollen tube cell. The generative cell is contained within the larger pollen tube cell. Upon germination, the tube cell forms the pollen tube through which the generative cell migrates to enter the ovary.
Explanation:
Oil, oil is made from things that has died thousands/millions of years ago.
Answer:
b. transitions
c. transversions
second
A. Crossing over between homologous chromosomes.
The scientific method is an empirical method of acquiring knowledge that has characterized the development of science since at least the 17th century. It involves careful observation, applying rigorous skepticism about what is observed, given that cognitive assumptions can distort how one interprets the observation. It involves formulating hypotheses, via induction, based on such observations; experimental and measurement-based testing of deductions drawn from the hypotheses; and refinement (or elimination) of the hypotheses based on the experimental findings. These are principles of the scientific method, as distinguished from a definitive series of steps applicable to all scientific enterprises.
Option A, at mid-ocean ridges, is the correct answer.
The topmost layer of the nautical share of a tectonic plate is known as the Oceanic crust. The Ocean Ridge is created as an effect of raising up of magma from the asthenosphere. Mid-ocean ridges are a large, seismically activated submarine elevation system located in the center of the basin of an ocean and considering the situation of the up-welling of magma connected with seafloor expanding. Thus they are as thick as 6 Km at the mid-ocean ridges.
