Answer:
Exosphere -The exosphere layer is mainly composed of extremely low densities of hydrogen, helium, and several heavier molecules including nitrogen, oxygen, and carbon dioxide closer to the exobase. The atoms and molecules are so far apart that they can travel hundreds of kilometers without colliding with one another.
Thermosphere - The aurora (Northern Lights and Southern Lights) mostly occur in the thermosphere. The thermosphere is a layer of Earth's atmosphere. The thermosphere is directly above the mesosphere and below the exosphere. ... Temperatures in the upper thermosphere can range from about 500° C (932° F) to 2,000° C (3,632° F) or higher.
Mesosphere- Most meteors burn up in the mesosphere. A type of lightning called sprites sometimes appears in the mesosphere above thunderstorms. Strange, high-altitude clouds called noctilucent clouds sometimes form in this layer near the North and South Poles.
Stratosphere-The stratosphere is the second major atmospheric layer above the troposphere, extending in altitude from about 8 to 30 miles high. No weather occurs in the stratosphere. The statosphere contains over 15% of the total mass of the atmosphere, and is where the ozone layer is located.
Troposphere-The troposphere is the lowest layer of Earth's atmosphere, and is also where nearly all weather conditions take place. It contains 75% of the atmosphere's mass and 99% of the total mass of water vapour and aerosols.
i hope this helps, good luck :)
Answer:
D
Explanation:
DNA stands for deoxyribonucleic acid, while RNA is ribonucleic acid. Although DNA and RNA both carry genetic information, there are quite a few differences between them. This is a comparison of the differences between DNA versus RNA, including a quick summary and a detailed table of the differences
The right answer is metaphase II.
The process is performed in two nuclear and cytoplasmic divisions, called first and second meiotic division or simply meiosis I and meiosis II. Both include prophase, metaphase, anaphase, and telophase. First division prophase is long and consists of 5 stages: leptotene, zygotene, pachytene, diplotene, and diakinesis. It is at this point that genetic recombination takes place at the level of chiasmus.
During meiosis I, the members of each homologous pair of chromosomes are paired during prophase, forming bivalents. During this phase, a protein structure, called synaptonemal complex form, allows recombination between homologous chromosomes. Subsequently, a large condensation of the bivalent chromosomes occurs and go to the metaphase plate during the first metaphase, resulting in the migration of n chromosomes to each of the poles during the first anaphase. This reduction division is responsible for maintaining the number of chromosomes characteristic of each species.
In meiosis II, as in mitosis, the sister chromatids comprising each chromosome are separated and distributed between the nuclei of the daughter cells. Between these two successive steps, there is no DNA replication. The maturation of the daughter cells will result in the gametes.
Around 4.1 billion years ago the first single celled organism appeared
