Answer:
b.burning of fossil fuels
Explanation:
Burning fossil fuels has been considered controversial since it produces tons and tons of CO2 and CO2 is considered a green house gas which is contributing to climate change.
Photosynthesis and planting trees actually sucks Carbon dioxide out of environment. Perspiration doesn't produce CO2.
When a pathogen comes in contact with your body, it has to breach the first line of defense to get inside. Your skin and mucus membranes are the main barrier here. Mucus traps the pathogens, and then is forced out of your body when you cough or blow your nose. Your skin also secretes chemicals that have antiviral properties, killing viruses on contact. If the pathogens get through that defense, the next line is non-specific immunity cells that patrol your tissues engulfing pathogens. There are other cells that do this, like macrophages, but the dendritic cells are most important for activating the third line of defense in your body.
Dendritic cells reside in your tissues, waiting for an invader to arrive. When they do find one, they engulf it and digest it. After they do this, they select pieces of the invader called antigens and put them on their surfaces. The dendritic cells migrate back to lymph nodes, key locations in your body filled with immune cells. There, they show the antigens, called antigen presentation, to two types of lymphocytes, T-cells and B-cells, activating them for a full immune response.
Answer:
D.
Explanation:
The first two options, A and B, can be eliminated because we know that the growth rate must be negative — more people are dying than are being born!
The term "per capita" means per person. Which answer makes more sense, losing 1.2 people per person or 0.12 people per person? While both might be a little confusing, you can't lose more than one person per person! Therefore, the answer is D.
3. Decreased variation in the shades of red because no form of the trait is advantageous.
