Chemical factors: This is due to internal stimuli. Changes in the blood such as decrease in O2, increase in CO2 and decrease in PH cause impulse in the carotid artery which stimulates the respiratory centers in the medulla and cause breathing.
Mechanical factors: also called external stimuli. Compression of the fetal chest during delivery forces small amount of lung fluid out of the lungs. This increase in pressure in the chest draws air into the lungs.
Answer: differences in reproducti<span>ve systems
</span>Fat in normal women is between 18% and 20% of body weight, and in normal men it represents 10% to 15%.
Women are ready to nourish a
fetus and then a baby from their own reserves, so women have to stock more
energy and the best way is in the form of fat in anticipation of future pregnancies.
There are many facts about arachnids.
Here are some:
1. Arachnids are invertibrates (No backbone)
2. Arachnids include spiders, mites, harvestmen, and pseudoscorpions.
The scientific name is Arachnida, and the higher classification name is Chelicerata.
Answer:
Explanation:
The cells in our bodies need oxygen to stay alive. Carbon dioxide is made in our bodies as cells do their jobs. The lungs and respiratory system allow oxygen in the air to be taken into the body, while also letting the body get rid of carbon dioxide in the air breathed out.