D) earthquake
Earthquakes release gases into the atmosphere.
Comparing DNA
Darwin could compare only the anatomy and embryos of living things. Today, scientists can compare their DNA. Similar DNA sequences are the strongest evidence for evolution from a common ancestor. Look at the diagram in Figure 9.3
Red blood cells actually carry the nutrients
Answer:
d. secondary endosymbiosis.
Explanation:
- When a living cell acquires another organism that eventually becomes a part of this cell, this process is known as primary endosymbiosis.
- When an organism that has already undergone primary endosymbiosis engulfs another eukaryotic organism then this process is known as secondary endosymbiosis.
- Secondary endosymbiosis has been known to occur in plastids because of which they are surrounded by two membranes. This bilayer is present because one of the layers is the original outer membrane of the organism and the other membrane is that of the organism that has been engulfed.
