Answer:
Coughing, Skin to skin contact, kissing, sneezing, touching something others have touched.
There are four major classes of biological macromolecules:
carbohydrates.
lipids.
proteins.
nucleic acids.
Answer:
Amino acids are molecules used to build proteins. All amino acids have a central carbon atom surrounded by a hydrogen atom, a carboxyl group (COOH), an amino group (NH2), and an R-group. It is the R-group or side chain that differs between the 20 amino acids.
1= Cerebrum.
2=Ventricles (fluid-filled spaces)
3.Cerebellum.
4.Brain stem (Pons and Medulla)
5.Spinal cord.
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