DUAL CREDIT BIOLOGY — Semester One Exam Review

What charge does oxygen have in a water molecule?

Partial negative (6-)

What charge does hydrogen have in a water molecule?

Partial positive (6+)

How many covalent bonds can carbon make?

4

What atom has 11 protons?

Sodium (Na)

What atoms are most likely to form chemical bonds?

Atoms with incomplete valence shells

What is the basic structure of an amino acid?

Central carbon bonded to amino group (NH₂), carboxyl group (COOH), hydrogen, and R group

How can you tell if an amino acid is nonpolar?

The R group is mostly carbon and hydrogen

What charge does a cation have?

Positive (+)

What charge does an anion have?

Negative (-)

What type of bonds are found in unsaturated fats?

Double covalent bonds between carbon atoms

What is the role of a buffer?

Maintains stable pH by absorbing acids or bases

What is homeostasis?

Maintaining stable internal conditions

What is adhesion?

Attraction between different substances

What are the three parts of the cell theory?

All living things are made of cells; the cell is the basic unit of structure and function; all cells come from pre-existing cells

Which part of a phospholipid is hydrophobic?

Fatty acid tails

Which part of a phospholipid is hydrophilic?

Phosphate head

What structures are found in prokaryotes?

Cell membrane, cytoplasm, ribosomes, cell wall, nucleoid region

What is the function of carbohydrates?

Quick energy and short-term energy storage

What is the function of lipids?

Long-term energy storage, insulation, and cell membranes

What is the monomer of proteins?

Amino acids

What is one function of proteins as enzymes?

Speed up chemical reactions

What structural role do proteins have?

Provide support such as muscle, hair, and skin

How do proteins help with transport?

They carry substances like oxygen

What happens to a cell in a hypertonic solution?

Water leaves the cell and it shrinks

What happens to a cell in a hypotonic solution?

Water enters the cell and it swells

What happens to a cell in an isotonic solution?

The cell stays the same size

How are active and passive transport the same?

Both move substances across the cell membrane

During active transport, molecules move in which direction?

From low concentration to high concentration

What is cellulose?

A structural carbohydrate in plant cell walls

What is the major difference between light-dependent and light-independent reactions?

Light reactions require light; the Calvin cycle does not directly

Why do mitochondria have a double membrane?

To increase surface area and separate reactions for ATP production

What is a carotenoid?

An accessory pigment that absorbs light and gives red, orange, and yellow colors

What are the products of the light reactions?

ATP, NADPH, and oxygen

How does ATP synthase make ATP?

Uses a proton (H⁺) gradient to produce ATP

What is required for the Calvin cycle?

CO₂, ATP, and NADPH

What is the function of the light reactions?

Convert light energy into chemical energy

What product of photosynthesis is used in cellular respiration?

Glucose

What molecules are formed during the Krebs cycle?

ATP, NADH, FADH₂, and CO₂

What is the net gain of ATP during glycolysis?

2 ATP

What molecules are electron carriers sent to the ETC?

NADH and FADH₂

What is the final electron acceptor in cellular respiration?

Oxygen

Where does glycolysis occur?

Cytoplasm

Where does the Krebs cycle take place?

Mitochondrial matrix

Where does the electron transport chain occur?

Inner mitochondrial membrane

What part of cellular respiration occurs without oxygen?

Glycolysis

Where are H⁺ ions pumped during the ETC?

Intermembrane space

What is the sequence of electrons in cellular respiration?

Glucose → NADH/FADH₂ → ETC → Oxygen

What happens to enzymes over time?

They can denature but are not used up

What molecules are produced during yeast fermentation?

Ethanol and carbon dioxide

Why do muscles become fatigued and painful?

Lactic acid buildup

What process occurs when oxygen is not present?

Fermentation