Oxygen.
Oxygen was fatal when organisms started using photosynthesis, this event was known as the Great Oxidation Event.
Answer:
Heliotropism
Explanation:
it's a type of tropism which is when a plant moves to where the sun is at because something is blocking it from getting sunlight which is why it moves to the sun
Answer:
Astrocytes.
Explanation:
Astrocytes are the star shaped cells that are present in the brain and spinal cord. The exact constitution of astrocytes in the brain is not known and almost 20% to 40% astrocytes are present in brain.
The astrocytes acts as the blood brain barrier and involved in the process of brain scarring. Astrocytes also regulate ions concentration by propagating the calcium ion channels in response to the stimulus. Astrocytes also generate a response by the calcium dependent release of glutamate.
Thus, the correct answer is option (B).
Respiratory system= breathing system
To keep our Respiratory system healthy we should:
1- never breathe in front of polluted areas
2- never pollute our areas
3- try to make our environment normal
Answer:
Mitochondria are double membrane bound cytoplasmic organelles present in most eukaryotic cells. They are responsible for aerobic respiration.
Explanation: