Protists obtain food in 3 ways. They produce their own organic molecules, ingest, and absorb. Ingestive protists ingest food, or engulf bacteria. These protists extend their cell wall and cell membrane forming a food vacuole around the food item. Inside the food vacuole, enzymes digest the food. Absorptive protists on the other hand, absorb food molecules across their cell membrane which takes place through diffusion. Absorptive protists play a key role in decomposition. They are considered as important decomposers. Major producers like photosynthetic protists use light energy to manufacture their own food.<span>
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Emperor penguins have the ability to 'recycle' their own body heat. The arteries and veins lie close together so that blood is pre-cooled on the way to a penguin's feet, wings and bill and warmed on the way back to the heart. Emperors' feet are adapted to the icy conditions
<u>Answer:</u>
An example situation of artificial selection is "More African elephants today naturally lack tusks compared to the elephant populations 100 years ago, because big game hunters sought elephants for ivory".
<u>Explanation:</u>
- The process of breeding animals to acquire the desired characteristics by the external means other than natural selection and behavior of animal itself is called as artificial selection.
- The first artificial selection was carried out by Darwin when he mated penguins that would have a higher chance of breeding.
- The practice of artificial selection was existing in human civilization a long time ago.
- This process was used to use wild animals and domestic animals in battles and other household works.
Answer:
Contact the Centers for Disease Control and Prevention (CDC).
Explanation:
When stress becomes long-term and is not properly addressed, it can lead to a number of more serious health conditions, including depression. It's high blood pressure.
