Answer:
The three parts of the cell theory are: cells are the smallest unit of life; all cells come from preexisting cells; and living thing is made up of one or more cell.
The skin is composed of thin membranous tissue that is quite permeable to water and contains a large network of blood vessels. The thin membranous skin is allows the respiratory gases to readily diffuse directly down their gradients between the blood vessels and the surroundings. When the frog is out of the water, mucus glands in the skin keep the frog moist, which helps absorb dissolved oxygen from the air.
A frog may also breathe much like a human, by taking air in through their nostrils and down into their lungs. The mechanism of taking air into the lungs is however sligthly different than in humans. Frogs do not have ribs nor a diaphragm, which in humans helps serve in expand the chest and thereby decreasing the pressure in the lungs allowing outside air to flow in.
In order to draw air into its mouth the frog lowers the floor of its mouth, which causes the throat to expand. Then the nostrils open allowing air to enter the enlarged mouth. The nostrils then close and the air in the mouth is forced into the lungs by contraction of the floor of the mouth. To elimate the carbon dioxide in the lungs the floor of the mouth moves down, drawing the air out of the lungs and into the mouth. Finally the nostrils are opened and the floor of the mouth moved up pushing the air out of the nostrils.
Frogs also have a respiratory surface on the lining of their mouth on which gas exchange takes place readily. While at rest, this process is their predominate form of breathing, only fills the lungs occasionally. This is because the lungs, which only adults have, are poorly developed.
Answer:
No. They will need to repeat their experiment several times, since the weather and times were different both days.
Explanation:
When a scientific experiment is conducted, one independent variable shall be changed in each experiment at a time so that the results of the experiment are authentic and we can easily determine which independent variable caused a change in the dependent variable.
If more than one independent variable is changed in the same experiment, then it will be difficult to interpret that which variable caused the change.
<u><em>Similarly, Maria and her brother need to repeat their experiment several times with just changing one variable at a time. </em></u>
Answer:
What are some differences between a food chain, web, or energy pyramid? Food chains show a limited feeding relationship between only a few organisms. Energy pyramid is the visual representation of the amount of energy, population, or biomass at each trophic level.
Answer:good because it help plant
Explanation:
