Answer:
The correct answer will be option-E.
Explanation:
The papillary muscles are the small muscles which arise in ventricles of the heart. These muscles are attached to the atrio-ventricular valves of the heart through chordae tendineae made up of fibrous tissues.
These muscle help prevent the backflow of the blood to the atria during ventricular systole or contraction. These muscle gets activated before the contraction which pulls the chordae tendinae attached to the cusps of the valve, thus closes the leaflets.
Thus, option- E is the correct answer.
Jellyfish, corals, and hydras belong to the group of animals called cnidarians.
The main characteristic of this group is that all of its members possess specialized cells called cnidocytes which often produce venom and have a role in capturing the animals prey.
Chemotherapy and/or stem cell transplant
