Ch:3 Anatomy CLASS Notes

What elements make up 96% of the human body?

Oxygen, carbon, hydrogen, and nitrogen.

Why is the balance of elements essential to life?

Each element is essential for various biological processes.

What is matter?

Anything that takes up space and has mass.

What are elements?

Pure substances that cannot be broken down into smaller substances.

What are compounds?

Combinations of two or more elements through bonding.

How many of the 92 naturally-occurring elements are found in the human body?

24 elements.

What are the major elements found in the body?

Oxygen, carbon, hydrogen, nitrogen, calcium, and phosphorus.

What is the role of trace elements in the body?

They constitute a small percentage of body weight but are essential for certain functions.

What defines an atom?

Atoms are made of subatomic particles: protons, neutrons, and electrons.

What is the charge of protons, neutrons, and electrons?

Protons are positive, neutrons are neutral, and electrons are negative.

What are isotopes?

Atoms with the same number of protons but different numbers of neutrons.

What is a radioisotope?

An unstable isotope that emits radiation.

How do chemical bonds form?

Atoms bond by using their valence electrons to achieve stability.

What are ionic bonds?

Bonds formed when one atom transfers an electron to another atom.

What are electrolytes?

Compounds that ionize in water and create solutions that can conduct electricity.

What are covalent bonds?

Bonds formed when two atoms share one or more pairs of electrons.

What are hydrogen bonds?

Weak attractions between hydrogen atoms in one molecule and oxygen atoms in another.