Answer:
D. They find more things that are not understood
Explanation:
After discovering something, scientist tend to find something related that sparks their curiousity.
External respiration (correct answer) involves the exchange of oxygen and carbon dioxide within the environment.
The exchange of wastes through the skin is just called excretion by sweating.
There is no exchange of nutrients that occur in the lungs but rather absorption of nutrients is the function of the gastrointestinal tract.
The exchange of oxygen and carbon dioxide within the cell is called cellular respiration and involves carrying oxygen from the blood to the cell then the cell uses it as the final electron acceptor in the electron transport chain. The metabolic wastes of the cell, primarily carbon dioxide, goes now to the bloodstream to be exchanged for oxygen in the lungs.
Fire is not a living thing, and abiotic factors are the factors in an ecosystem that are non-living. So, fire is an abiotic factor in an ecosystem, though its not mentioned alot.
Answer:
The four organelles that contribute to the synthesis, transport, packaging, and export of proteins to the extracellular environment are Nucleus, RIBOSOMES, rough endoplasmic recticulum and Golgi apparathus.
Explanation:
The nucleus is the organelle that produced RIBOSOMES.
RIBOSOMES are organelles responsible for protein synthesis production of proteins.
The protein produced by the RIBOSOMES are then gathered in the rough endoplasmic recticulum . It then export and transport the protein to Golgi apparatus. The Golgi apparatus modifies and package the protein.
Filling of the heart and needing to pump the blood back out at an also increased rate
