Astudent lifted weights after school and found that his muscles started to burn. he couldn’t continue to lift the weights after prolonged exercising. this muscle fatigue is most likely due to
(1)the heart beating too fast and tiring out
(2)the lungs accumulating oxygen
(3)lack of oxygen and build up of waste in the muscles
(4)lack of carbon dioxide in the muscles

Pls need ! in your opinion, what are the limiting factors that might affect the growth or diversity of our ecosystem? respond to this question in claim, evidence, reasoning format. 1. make your claim (i are the limiting factors that might affect the growth or diversity of our 2. follow the claim with 3 pieces of evidence. evidence may be taken from the reading, the videos, previous lessons, or googled answers. site sources, too. 3. use reasoning to explain why you chose your evidence.

Hairs that clean dirt out of the air in your nasal passages are called: a. sinus b. trachea c. cilia d. mucus

Under which of the following circumstances would natural selection not operate on an organism