Answer:
unicellular life first
Explanation:
it arose billions of years ago while multicellular life forms around at least 600 million years ago
Your answer should be options 4, 5, & 6.. correct me if I’m wrong !
B. the intensity o stimulus and the observer's criteria.
Answer:
excretory system and circulatory system
Explanation:
Blood is part of circulatory system and as it move through various organs it exchanges the gases i.e give oxygen to the cell and take carbon dioxide from them. After taking CO2, the blood becomes impure and hence it passes through the kidney before going to the heart. Kidney is part of excretory system which removes carbon dioxide from blood and thus purifies it.
Gene editing involves the change of genotype