An open circulatory system simply
means that the blood flows out of vessels and into the spaces or sinuses. Invertebrates,
insects and crustaceans has an open circulatory system where pump blood goes
into a hemocoel and diffusing back to the circulatory system between cells. In
other animals, the heart pumps the blood into the body cavities, spaces or
sinuses, where the blood surrounds the tissues.
It is also assists in creating body chemicals like hormones and enzymes that are needed for normal function. It provides energy (like carbohydratesdo) and keeps the immune system strong. Proteins are made up of amino acids, and dogs require 22 amino acids to make necessary proteins.
<span>the student could identify the catalyst by noticing the substance that makes a chemical reaction go faster. It will be written in a chemical equation.
Example of Catalyst :
- A corosion process of an iron will be faster if it exposed to Oxygen
- A burning process will be a lot of faster if it mixed with oil.</span>
Answer:
D. build them up and breaks them down
hope this will help :)