You breathe in oxygen, you exhale carbon dioxide.
It is safe but you shouldn't breathe in carbon dioxide all the time.
Answer:
Populations have variation in traits due to random mutation, crossing over and environmental conditions.
The answer is; E
This shows that these organelles were once free-living organisms with their own mechanisms for reproduction which they have retained even after years of symbiotic relationship with the higher organisms. During their duplication, they also replicate their own DNA. Their DNA does not have histones (as opposed to the DNA in the nucleus of their host eukaryotic cell) similar to that of simple organisms such as bacteria.
Answer:
The correct answer is - they lack a nucleus, DNA, and organelles like the endoplasmic reticulum or mitochondria
Explanation:
Red blood cells are considered as the cells, carry oxygen with the help of hemoglobin protein present in it to the various parts of the body from the lungs and carry CO2 back to the lungs.
These cells are different from the normal cell as they do not participate in the protein synthesis due to the fact that they lack various cell organelle and cell components required. Nucleus and DNA are major components or organelle missing from these cells. In addition to these two, endoplasmic reticulum and mitochondria also missing from RBCs.
I think homologous structures is a great example and idea that supports the theory of evolution. Homologous structures shows us how our futures evolved by natural selection.