Answer:
Explanation:
Hydrogen bonding is a special type of dipole-dipole attraction between molecules, not a covalent bond to a hydrogen atom. It results from the attractive force between a hydrogen atom covalently bonded to a very electronegative atom such as a N, O, or F atom and another very electronegative atom.
The oxygen level in the garden is higher because plants produce oxygen through photosynthesis. The city has a lower level of oxygen because cars are releasing exhaust containing carbon monoxide.
Answer:
I would say B
Explanation:
To prove Causation you need a random experiment. This could mean D because random experiments entail hidden variables but I think your best bet is B because its what's the use of a hidden variable without an experiment.
Answer:
Vascular Plants have special vessels that help the plant carry water and sunlight/food throughout the plant, making it survive in conditions where the place has enough sunlight and water. Non vascular plants however don't rely on these, as they rely on the moist locations in places like South America and Hawaii, and dont rely on roots for water comsuption.
Explanation:
A) inform the white blood cells of the invader so it can be destroyed. This works because antigens are proteins, and proteins have unique complex structures; the combination of antigens on the surface of a pathogen will each cause an immune response in the body, and ultimately white blood cells are part the immune system responses to destroy this pathogen.