Unit 1: Chemistry of Life (copy)

Elements are substances that cannot be broken down into simpler substances by __ means.

chemical

The four main elements used to build biological molecules are __, __, __, and __.

oxygen, carbon, hydrogen, nitrogen

Some elements, like iron (Fe) and iodine (I), are called __ elements because they are required only in very small quantities.

trace

Atoms are the unit of life and are the __ of the physical world.

building blocks

Protons are positively charged (+) particles, while __ are uncharged particles.

neutrons

A __ bond is formed between two atoms when one or more electrons are transferred from one atom to the other.

ionic

If electrons are shared equally between the atoms, the bond is called a __ covalent bond.

non-polar

Hydrogen bonds are weak chemical bonds that form when a hydrogen atom is __ bonded to another atom.

covalently

The ability of water to rise up the roots and trunks of trees is called __ action.

capillary

A solution is considered __ if it contains a lot of hydrogen ions (H+).

acidic

The pH scale ranges from 1 to 14, with 7 being considered __ pH.

neutral

Molecules that contain carbon are referred to as __ molecules.

organic

Polymers are chains of building blocks in __.

macromolecules

Polysaccharides are made up of many repeated units of __.

monosaccharides

When two monosaccharides are joined, the bond is called a __ linkage.

glycosidic

Proteins are important for structure, function, and __ of your tissues and organs.

regulation

The bond between two amino acids is called a __ bond.

peptide

The most common examples of lipids are triglycerides, phospholipids, and __.

steroids

Phospholipids have two fatty acid tails and one negatively charged __ head.

phosphate

Cholesterol is a four-ringed molecule that is found in __.

membranes

Nucleic acids contain carbon, hydrogen, oxygen, nitrogen, and __.

phosphorus

DNA contains the hereditary __ of all life.

blueprints