14. Dermis
15. Chemical
17. Virus
18. Antibodies
19. Gas exchange
20. Ligament
Hope this helps!
Trace fossil because a trace fossil is a fossil of a footprint, trail, burrow, or other trace of an animal rather than of the animal itself.
Answer: It's not blocked
https://www.khanacademy.org/science/high-school-biology/hs-human-body-systems/hs-body-structure-and-homeostasis/a/tissues-organs-organ-systems
The correct answer is a structure that would differentiate the hollow heart into chambers to separate oxygenated blood.
The heart has four chambers: two ventricles and two atria. The right atrium gets oxygen-poor blood from the body and pumps it to the right ventricle. The right ventricle pumps the oxygen-deficient blood to the lungs.
The left atrium gets oxygen-enriched blood from the lungs and pumps it to the left ventricle, and the left ventricle pumps the oxygen-enriched blood to the body. The right and left atrium are distinguished by a wall of tissue known as the atrial septum, and the left and right ventricles are separated by the ventricular septum.
Answer:
A
Explanation:
insecticides are safe to use
