I would say the answer is C
Galaxy
- It is a collection of billions of stars.
- Resembling human beings or animals.
- There are billions of galaxies in the Universe.
- There are not many galaxies, which are visible to the naked eyes.
Constellation
- It is a collection of only a few stars.
- Stars in the constellation are arranged in patterns resembling human beings or some animals.
- There are only about 88 constellations.
- There are many constellations, which can be observed with the help of naked eyes.
<u>Answer:</u>
Free-living flatworms have developed a nervous system which helps them to sense the food. They have a head at one end of the body and each side of the head has sensory cells. These cells help them to sense chemicals and other movements around them.
While Parasitic flatworms don't have any nervous or digestive system as they live on the food digested by the host. They have special hooks attached to their head which help them to attach a host. They have developed some covering called 'teguments' which protect them from digestive liquids.
Answer: There are two possible effective choices
A. Start contour plowing on the slopes where landslides happen.
E. Reduce the slopes where landslides occur.
Explanation:
Plowing can help flow water through the slopes instead of it all building up in one area all at once. But reducing the slopes can slow landslides due to the smaller incline, but will not completely get rid of them.
Answer and Explanation:
To promote a good DNA extraction through the Chelex extraction protocol, it is important to follow some measures, which are essential for the entire process to take place efficiently.
The most important measure is to avoid contamination. In this case, all surfaces, container and substances used must be properly sterilized, preventing unnecessary elements from coming into contact with the DNA sample or the protocol reagents.
It is important that the researcher is wearing clean, appropriate clothing and gloves when using this protocol. This avoids impurities and contamination with the researcher's DNA.
Another precaution must be taken with the DNA sample and the reagents that will be used during the extraction. All must be stored correctly, preventing their degradation, especially the DNA, which is a very unstable molecule.
Finally, the researcher must strictly follow all the steps of the protocol as indicated.
Answer: cumulus
Explain: cumulus clouds are clouds with flat bases are often described as puffy, cotton-like, or fluffy on appearance.
Cumulus clouds often precursors of other types of clouds, such as cumulonimbus, when influenced by weather factors such as instability, moisture, and temperature gradient.
