Question

Where in our environment does our body obtain the oxygen it needs? What two systems are responsible for obtaining the oxygen and delivering it to the cells?
What system provides the nutrients that the cells will convert to energy?

During the process of making energy, our cells produce waste products. What systems are used to expel CO2?

What are the systems that are used to eliminate solid and liquid wastes?

Describe the relationship between the bones and muscles for movement, and the other systems that are necessary for the bones and muscles to function.

What systems are responsible for meiosis and what are the results?

Answer 1

Answer:

We get oxygen from the air i.e. atmosphere. Green plants release oxygen in the atmosphere as a byproduct of photosynthesis. Respiratory system is responsible for obtaining oxygen from the environment. Circulatory system on other hand helps in delivering this oxygen to different cells of the body with the help of blood.

We get nutrients from the food that we eat. Digestive system breaks down all the complex compounds (such as polysaccharides, polypeptides, fats etc) into simpler elements which are easy to absorb.  

$CO_{2}$ produced as a waste product by the cells is carried by the blood to alveoli in the lungs where it gets diffused out and come out of the body as a part of exhale air. Hence, circulatory system helps in he transportation of $CO_{2}$ from cells to the lungs and respiratory system helps in expelling it out from the lungs to the outside environment.

Solid wastes are mainly excreted out of the body from anus which is a part of digestive system. On the other hand, liquid waste (urine) is excreted out of the body with the help of urethra which is the part of excretory system. In addition, excess salts and water can also excrete out of the body through skin.

Muscles and bones together help us in our locomotion. Nervous system is important for proper functioning of bones and muscles.

Meiosis is the type of cell division used to produce haploid cells or gametes from a diploid parent cell. Hence, it is used in reproduction system to produce sperm in males and eggs in females.