Answer:
Atmosphere refers to the thin blanket of air that surrounds the earth.
It serves many important functions such as:
- It contains a mixture of gases that are essential for the existence of life on earth. For example, carbon dioxide is essential for photosynthesis and oxygen is essential for cellular respiration.
- It also serves as the reservoir of water in the form of water vapor. Thus, it forms an important constituent for the water cycle.
- It maintains the temperature of the earth. Through the greenhouse effect, it maintains the temperature of the earth in limited ranges.
- It protects the earth from harmful rays of the sun. For example, ozone inhibits the entry of most of the UV rays of the sun into the earth environment.
This answer would be all of the above
Answer:
b. 2N meiosis 1N fertilization 2N
Explanation:
In eukaryotic organisms, gamete mother cells are diploid (2N) and have two complete sets of chromosomes. Meiosis in male and female gamete mother cells form haploid male and female gametes (N) respectively. This occurs since meiosis reduces the number of the chromosome to half in the daughter cells. The fusion of haploid male and female gametes during fertilization restores the diploid chromosome number of the species and forms diploid zygote (2N). Repeated mitotic divisions in the diploid zygote form the diploid organism.
B, hormones that serve as chemical messengers im not 100% sure though
Answer: Ice cores.
Explanation: Ice cores are commonly studied by scientists to find out what the climate was like decades and centuries ago.
