Q: Hormones, ions, and neurotransmitters are all types of what? Choices: - nutrients - pathogens - proteins - chemical signals A:
chemical signals

(Question)
Q: What is considered to be a unique feature of echinoderms? Choices: - oil vascular system - air vascular system - iron vascular system - water vascular system A:
(Answer)
water vascular system

Ques: Q: What is it called when breaks in bone occur that is usually caused by excessive stress on the bone? Choices: - fragments - faults - ruptures - fractures A:
Ans: fractures

(Q).
Q: Most members of the animal kingdom have differentiated tissues of four main classesnervous, muscular, connective, and this? Choices: - neural - crystalline - digestive - epithelial A:
(A).
epithelial

Ques:Q: What are plastids that contain other pigments? Choices: - chloroplasts - lucoplasts - cytoplasm - chromoplasts A:

Ans:chromoplasts

Question: Q: Scientists think the solar system formed from a big cloud of gas and dust called what? Choices: - comet - supernova - Oort cloud - nebula A:
Answer:
nebula