Answer:
They accurately compare the current atmosphere with the previous one, by assessing the amount of atmospheric gases present today, with the amount of atmospheric gases trapped in ice cores that they believe are millennial, that is, they have existed for thousands of years ago.
Explanation:
As we know, it is difficult to compare current characteristics of the planet earth with characteristics that the planet had in the past, thousands of years ago. This is because the ancient characteristics on earth are not fully available to be analyzed, since most of them have been modified over time.
To do this, scientists need to find factors that may have existed thousands of years ago and assess whether these factors have any account of the characteristics of the earth. In the case of atmospheric characteristics, it is common for scientists to compare the current atmosphere with the atmosphere of thousands of years ago, with the assessment of the amount of atmospheric gases trapped in ancient ice cores, with the amount of atmospheric gases present in the atmosphere today.
Chromosomes females have xx and males are xy
Answer:
10
Explanation:
The cell cycle is composed of three states: interphase, cell division and resting.
The interphase is composed of 3 phases: G1, S and G2 (in this order). During this state the cell prepares itself for cell division. As part of the preparation the cell duplicates all its genetic material, that is, all its chromosomes. This duplication is done during the phase S.
During the meiotic cell division (composed of meiosis 1 and meiosis 2) a single diploid mother cell (with duplicated chromosomes) produces four haploid daughter cells. the meiosis 1 produces two haploid cells with duplicated chromosomes, and the meiosis 2 produces 4 haploid cells with normal chromosomes (no duplicated).
If a germ-line cell from a frog contains 10 picograms of DNA during G1, then this cell will have 20 picograms of DNA before the product of the first meiotic division, and will have 10 picograms at the begining of the meiosis 2 (i.e prophase II)
Answer:
The main difference between red brown and green algae is that red algae contain chlorophyll a, chlorophyll d, and phycoerythrin, while brown algae contain chlorophyll a, chlorophyll c, and fucoxanthin and green algae contain chlorophyll a, chlorophyll b, and xanthophylls.