Biologists recognize five levels of cell organization. The lowest and simplest is the cellular level. Organisms here are either unicellular organisms, like protozoa, or colonial organisms. Colonial organisms are composed of single-celled individuals that stay together to sustain the life of the whole colony. Next on the scale of complexity is the level occupied by tissue. A tissue is a group of similar cells that perform a similar activity. Tissues that are organized around a common function together make up an organ, the third level of complexity. The fourth level of organization is the system, formed by a group of organs that together perform a specific bodily process. The fifth and highest level is the organism level, in which body systems work together in a structure capable of independent life.
Answer:
from precipitation, oceans lakes streams and soil
Answer:
No, cardiac muscle tissue does not exhibit recruitment.
Explanation:
The cardiac muscle tissue does not recruit cells to contract. The reason is that the cardiac muscle contracts all its cells at once and with the same force. It does not have to recruit other cells since it does not have to lift objects of different weights. The heart's contraction aims to pump blood and to do it rhythmically. The heart has a natural peacemaker, the sinoatrial node. The Sinoatrial node transmits an electrical impulse to all the heart to contract it all at the same time and continuously. For these reasons, the cardiac muscle does not need recruitment.
