The main reason for the difference in the mass extinction occurring today and previously is the pace of the current extinction. The extinction is taking place globally and involves hundreds of species at the same time. In less than 50 years, we have lost numerous species. In contrast to this, previously during the mass extinction, only a few species were lost, and other managed to survive. But, not the status is opposite due to the magnitude of the extinction.
Answer: B - People with two copies of the mutated gene have sickle-cell anemia. People with one copy of the mutated gene have both healthy and misshapen red blood cells and are carriers of the disease.
Explanation:
Co-dominance is when both the alleles of a gene in a heterozygote show. In the case of sickle cell anemia (since it is a co-dominant trait) even if the person only has one sickle cell allele, symptoms of sickle cell will still show up in that person. That's why the person in this example has both misshapen and healthy red blood cells.
Answer:
In 1928, Sir Alexander Fleming was studying Staphylococcus bacteria growing in culture dishes. He noticed that a mold called Penicillium was also growing in some of the dishes. A clear area existed around the mold because all the bacteria that had grown in this area had died. In the culture dishes without the mold, no clear areas were present.
Fleming thought that the mold must be producing a chemical that killed the bacteria. He decided to isolate this substance and test it to see if it would kill bacteria. Fleming transferred the mold to a nutrient broth solution. This solution contained all the materials the mold needed to grow. After the mold grew, he removed it from the nutrient broth. Fleming then added the nutrient broth in which the mold had grown to a culture of bacteria. He observed that the bacteria died. He also added the same type of broth that had not been exposed to the mold, to a culture of the same type of bacteria. Nothing happened to the bacteria.
Explanation:
n 1928, Sir Alexander Fleming was studying Staphylococcus bacteria growing in culture dishes. He noticed that a mold called Penicillium was also growing in some of the dishes. A clear area existed around the mold because all the bacteria that had grown in this area had died. In the culture dishes without the mold, no clear areas were present.
Fleming thought that the mold must be producing a chemical that killed the bacteria. He decided to isolate this substance and test it to see if it would kill bacteria. Fleming transferred the mold to a nutrient broth solution. This solution contained all the materials the mold needed to grow. After the mold grew, he removed it from the nutrient broth. Fleming then added the nutrient broth in which the mold had grown to a culture of bacteria. He observed that the bacteria died. He also added the same type of broth that had not been exposed to the mold, to a culture of the same type of bacteria. Nothing happened to the bacteria.
Begins to decline and die off, because other organisms are competing for those same resources
Answer:
They concluded that the cell is eukaryotic cell.
Explanation:
Prokaryotic and eukaryotic cells are the two types of organisms. Prokaryotic organisms are the organisms made up of prokaryotic cells and eukaryotic organisms are made up of eukaryotic cells.
Prokaryotic cells do not have a nucleus and other membrane-bound organelle and eukaryotic cells have a nucleus and other membrane-bound organelles like mitochondria.
Therefore if the cell has mitochondria they must conclude that the cell is eukaryotic because the prokaryotic cell does not have mitochondria as it is a membrane-bound organelle.
