An ecologist conducts<span> a </span>greenhouse experiment<span> to </span>study<span> the </span>effect<span> of nitrogen </span>concentration<span> on the</span>productivity<span> of </span>sunflower seedlings<span>. What is the </span>independent variable<span> in this </span>experiment<span>? make predictions about how nature works</span>
They breathe through their skin. Air dissolves on the mucus of their skin, so they MUST stay moist to breathe.
If worms dry out, they suffocate. As fresh air is taken in through the skin, oxygen is drawn into the worm's circulatory system, and the worm's hearts pump the oxygenated blood to the head area.
Answer:
The first person to observe cells was Robert Hooke. Hooke was an English scientist. He used a compound microscope to look at thin slices of cork.
Explanation:
Sorry if I am wrong let me know if I am.
Answer:
Protists are a diverse collection of organisms that do not fit into animal, plant, bacteria or fungi groups. While exceptions exist, they are primarily microscopic and made up of a single cell (unicellular), according to the educational website CK-12.
Answer:
Vertebrates contain nervous system which is highly specialized organ.
Explanation:
The nervous system is the complex system in the vertebrate body which is composed of central nervous system that contain brain,spinal cord and peripheral nervous system which contain cranial nerve, spinal nerve,involuntary nerve etc.
The nervous system contain neurons that mainly transmit signal to the different parts of the body.
The peripheral nervous sytem contain somatic and visceral part.
The grey matter and white matter are the 2 areas in vertebrate nervous system.
