Answer:
Respiratory system and circulatory system.
The respiratory system allow living things to obtain oxygen from the air while the circulatory system allows oxygen to be carried around the body.
Explanation:
Two important ways by which humans have affected the carbon cycle, especially in recent history, are: 1) the release of carbon dioxide into the atmosphere during the burning of fossil fuels, and 2) the clearing of trees and other plants (deforestation) that absorb carbon dioxide from the atmosphere
Answer: when one is lost, one is formed
<h2>Answer:</h2>
Because same base pairs are arranged differently among organisms due to which there are so much variations in organisms.
<h3>Explanation:</h3>
- Variation in the organism is due to the genes.
- Every one have different DNA/genes which describes one's features.
- Genes are various arrangements of these four base pairs.
So same base pairs with different pattern arrangement causes variation among organism.
Answer:prophase----the chromosomes shorten and thicken.the nuclear membrane has open up and the nucleolus has disappeared
Metaphase----the chromosomes migrate to the central plane of the cell and attach to the spindle fibres microtubules
Anaphase---the chromatids of each chromosomes part and move towards opposite poles of the spindle as the spindle fibres shorten
Telophase----the chromatids are in the polar end of the spindle .the spindle breaks down,the centrioles replicate,the nuclear membrane is reformed,the chromosomes gradually uncoil.
Explanation:
