BIO 1810 Chapter 2 prep guide

What are the three major subatomic particles? and charges?

Protons (+), neutrons (0), and electrons (-).

Valence Shell

The outermost electron shells of atoms that determine chemical reactivity and bonding properties.

Ions

Charged atoms or molecules that perform critical elemental functions within the human body.

pH

A measure of acidity or alkalinity that forms a fundamental basis for biochemical reactions in the body.

Energy and Work

Core physics concepts that describe the capacity to perform activity and drive biochemical processes in the human body.

Proteins

One of the primary organic macromolecular building blocks of the human body.

Carbohydrates

A primary class of organic compounds serving as essential building blocks of the body.

Lipids

A major category of biological macromolecular building blocks in the human body.

Enzymes

Biological molecules that act as biochemical catalysts to regulate and drive chemical reactions in the body.

ATP

Adenosine triphosphate, a critical molecule vital to human physiology for driving biochemistry and cellular work.

Sodium-Potassium Pump

A vital biological transport mechanism in human physiology that utilizes energy to move sodium and potassium ions.

DNA & RNA

The basic nucleic acid components that carry and process genetic information in the body.

Where are protons and neutrons located?

nucleus

Atomic number

number of protons

Why are valence electrons important?

They largely determine an atom's chemical reactivity and bonding behavior.

When is an atom generally most chemically stable?

When its outer electron shell is filled.

What happens when an atom's outer shell isn't full?

It tends to gain, lose, or share electrons to become more stable.

What is a covalent bond?

A bond formed when atoms share electrons. Very strong

What is an ionic bond?

transfer of electrons, intermediate in strength

What are hydrogen bonds?

sharing of electrons with H, weak

What does pH measure?

The acidity/basicity of a solution, related to its hydrogen ion (H⁺) concentration.

What pH is neutral?

7

What pH is acidic?

Below 7

What pH is basic/alkaline?

Above 7

Which has more H⁺: pH 3 or pH 6?

pH 3. Lower pH = higher H⁺ concentration.

A solution changes from pH 7 to pH 6. What happened?

It became more acidic, and the H⁺ concentration increased 10-fold.

What is energy?

The capacity to do work.

What four elements make up most of the human body's mass?

Oxygen, carbon, hydrogen, and nitrogen (O, C, H, N).

What is oxygen (O) important for?

Water and aerobic cellular respiration/ATP production.

What is calcium (Ca²⁺) important for?

Bones/teeth, muscle contraction, cell signaling, and blood clotting.

What is potassium (K⁺) important for?

Membrane potentials, nerve signaling, and muscle function. It is a major intracellular cation.

What is chloride (Cl⁻) important for?

Fluid/electrical balance and acid-base physiology; it is a major extracellular anion.

What is phosphorus/phosphate important for?

ATP, DNA/RNA, phospholipids, and bones/teeth.

Which ion is found at a higher concentration outside most cells: Na⁺ or K⁺?

Na⁺

What percentage of the body is made up by C.H,O,N?

96%

What are the basic building blocks of carbohydrates?

Carbohydrates are made up of simple sugars called monosaccharides, which can combine to form polysaccharides. (carbon, hydrogen, oxygen)

What is a major function of carbohydrates?

They are an important source of readily available energy.

What are proteins building block?

Amino acid (Carbon, hydrogen, oxygen, nitrogen)

What are the building block for lipids?

fatty acids +Glycerol (C,H,O)

What are major functions of lipids?

Long-term energy storage, insulation/protection, membranes, and some signaling molecules/hormone

1g CHO (carbohydrates) is how many kcal?

4

1g fats/lipids is how many kcal?

9

1g protein is how many kcal?

4

Are enzymes consumed during the reactions they catalyze?

No. They can be reused.

How do enzymes speed up reactions?

They lower activation energy.

What is a substrate?

The molecule an enzyme binds to and acts upon.

Where does the substrate bind?

The enzyme's active site.

What can happen if an enzyme is exposed to extreme temperature or pH?

Its structure can change (denaturation), reducing or destroying its function.

An enzyme makes a reaction occur faster. Did it increase or decrease activation energy?

Decrease

What is oxidation?

Loss of electrons.

What is reduction?

Gain of electrons

Why is ATP important?

It is a major immediate energy-transfer molecule used to power cellular work.

What happens when ATP is hydrolyzed?

ATP → ADP + Pi, with energy becoming available for cellular processes.

What are the three major categories of cellular work powered by ATP?

Chemical, transport, and mechanical work.

What type of transport is the Na⁺/K⁺ pump?

Primary active transport.

What three components make up a nucleotide?

• Phosphate group

• 5-carbon sugar

• Nitrogenous base

What sugar is found in DNA?

Deoxyribose

What sugar is found in RNA?

Ribose

What is RNA's general role?

RNA has several roles in gene expression and protein synthesis.