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.
Answer;
a segment of chromosomal DNA
Explanation;
A gene is a hereditary unit consisting of a sequence of DNA that occupies a specific location on a chromosome and determines a particular characteristic in an organism. Genes undergo mutation when their DNA sequence changes.
It is the basic physical and functional unit of heredity. Genes are made up of DNA. Some genes act as instructions to make molecules called proteins. However, many genes do not code for proteins.
Alleles are forms of the same gene with small differences in their sequence of DNA bases. These small differences contribute to each person’s unique physical features.
A. The sun
Abiotic means fake or not living. Trees, grass, and people are living, also know as biotic. The sun is not living, it’s just a ball of hot gas, which is not living.