Pure breeding means the same as selective breeding since you take two animals and combine their traits for certain reasons
The functions of the NUCLEUS in the cell resembles the functions of the brain in higher animals. This is because, it is the nucleus that direct all the cell activities and it also contains the genetic material in form of DNA.
Methane is the gas that is strongly correlated with Earth's heating and cooling patterns. Did you know that cow's flatulence is methane gas?! Interesting fact!
The double membrane. It's theorized that chloroplasts used to be their own single-celled organism in the environment (and therefore with its own membrane). Then, the theory states, a larger cell took in the chloroplast by endocytosis, which involves surrounding the chloroplast in the large cell's own membrane. The chloroplast would then have two membranes surrounding it. This is similar to the thinking for mitochondria becoming an organelle as well. Hope this helps! :)
When food is digested, the food is broken down into Glucose, which can get into the bloodstream through the small intestines. It travels around the body in the bloods plasma and is then diffused into the body's cells through the capillaries. Once the Glucose is in the body cells, it can be used for respiration.
The breathing system is used in respiration because we need it to respire aerobically, so that our body gets all the vital oxygen it needs. When we breathe, oxygen is stored in the alveoli in the lungs. From there, it can be diffused into the bloodstream, to be used for respiration.
The products of aerobic respiration is Carbon Dioxide and Water. The Water leaves the body as sweat or waste such as urine. The Carbon Dioxide is carried through the blood to our lungs where we can breathe it out. Where as in anaerobic respiration, the product is Lactic Acid. This ends up being broken by oxygen after exercise (oxygen debt) and is also turned into Carbon Dioxide and Water.
