The basis of the process of Natural selection is the random mutation: some organisms develop random mutations which increase their chance for survival and they survive more likely than other organisms and reproduce.
So the correct answer is:
A) Through random mutations in DNA, some pests developed a resistance to the pesticide.
True! Earth is beginning to become very overcrowded and combined with the amount of people of the planet and the carelessness that they all have for it, the earth is slowly beginning to show it's age. Of course, no one will act on this opinion, because it is quite illegal to just kill people, but it is true!
After crystal violet staining, the Gram-positive bacteria may appear dark blue or violet. The cell wall of gram positive bacteria have thick peptidoglycan layer, thus it retains the crystal violet stain compared to gram negative bacteria.
Hope this helps! Have a good day!
<u>Answer</u>: The answers are matched as follows:
African forests have been hunted to near extinction levels to obtain ivory-------------->human exploitation
The eruption of mount Saint Helens destroyed some populations of conifers------> natural disasters
An infection with a fungus reduced the population of North American Elm trees ----> disease
Increasing global temperatures have altered migration patterns of humpback whales ------>climate change
<u>Explanation</u>:
- <em>Human</em> <em>exploitation</em> is the unethical or selfish use of resources to satisfy their own personal needs or for any profitable activity which harms the resources in such a way that they get limited. Humans have been hunting elephants to obtain ivory for many purposes such as making jewellery etc. and earning profits from it. Due to such extensive hunting they have driven the elephants to a level of extinction and thus, this is a form of human exploitation.
- Mount Saint Helens is a volcano and its eruption which harms the population of the trees in the area is a form of natural disaster since volcanic eruption is a <em>natural</em> <em>phenomena</em>.
- Fungal infection is a <em>disease</em> which is cause by the microorganisms which harms the population of the Elm trees.
- Increase of global temperature is a type of climate <em>change</em> and thus, this effect of alteration of migration pattern is caused by climate change.
Answer:
The excretory system helps the respiratory system by removing carbon dioxide that is produced during respiration (third option).
Explanation:
The lungs are in charge of the breathing process, being the main organ of the respiratory system. Each lung is considered an excretory organ —belonging to the excretory system— since it is capable of eliminating the carbon dioxide (CO₂) produced by the metabolism during expiration.
As a result of the gaseous exchange, the oxygen entering the lungs through the inhaled air passes into the blood, while the CO₂ is removed from the blood. This CO₂ is removed during expiration, which makes the lungs part of the excretory system.
The other options are not correct because:
- <em>The excretory system does </em><u><em>not introduce more oxygen into the lungs</em></u><em>.
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- <em>The </em><u><em>circulation of blood in and out of the lungs</em></u><em> is a function of the circulatory system.
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- <u><em>Urine is not produced by breathing</em></u><em>.</em>
