Biochemistry Study

Question 1

What are the different parts of an atom? Where is each part located and what are their charges?

Answer 1

• Proton: positive charge, located in the nucleus
• Neutron: no charge, located in the nucleus
• Electron: negative charge, orbits around the nucleus

Understanding the structure of an atom is fundamental in chemistry.

Question 2

List the three types of bonds discussed and give an example of each.

Answer 2

• Covalent bond: water, H2O
• Ionic bond: sodium chloride (salt), NaCl
• Van der Waals: geckos sticking to a wall

These bonds are essential in understanding molecular interactions.

Question 3

How does each of the different types of bonds form?

Answer 3

• Covalent: formed when atoms share electrons
• Ionic: formed through the attraction of 2 oppositely charged atoms
• Van der Waals: attractive force between positive and negative regions on atoms/molecules

Each bond type has unique characteristics and formation processes.

Question 4

What is the difference between a compound and a molecule?

Answer 4

• Compounds: formed when 2 or more atoms bond together using ionic or covalent bonds
• Molecules: specific types of compounds formed by covalent bonds

Examples include NaCl as a compound and H2O as a molecule.

Question 5

What is the charge of an atom that has given up an electron? One that has accepted an electron?

Answer 5

• Atom that gives up an electron: positive charge
• Atom that gains an electron: negative charge

This concept is crucial for understanding ionic bonding.

Question 6

What is a polar molecule? Explain why it’s polar.

Answer 6

A molecule is polar because hydrogen has a partial positive charge and oxygen has a partial negative charge

This occurs because oxygen attracts electrons more strongly due to its higher number of protons.

Question 7

How do hydrogen bonds form? Are they strong bonds?

Answer 7

Hydrogen bonds form when slightly positive hydrogens are attracted to slightly negative oxygens on another water molecule

They are weak bonds but strong enough for water striders to walk on water.

Question 8

How many hydrogen bonds can a water molecule form?

Answer 8

4

This property contributes to water’s unique characteristics.

Question 9

Know the difference between a covalent bond and a hydrogen bond.

Answer 9

• Covalent: atoms share electrons
• Hydrogen: attraction between positive and negative regions on different molecules

Covalent bonds are stronger than hydrogen bonds.

Question 10

What are the 5 properties of water discussed in class?

Answer 10

• Cohesion
• Adhesion
• Less dense as a solid
• High heat of vaporization
• High specific heat

Each property has significant implications for life on Earth.

Question 11

What is the difference between cohesion and adhesion?

Answer 11

• Cohesion: water binds to itself
• Adhesion: water binds to other things

Both involve hydrogen bonding.

Question 12

Describe capillary action. How do plants use it?

Answer 12

Plants use adhesion and cohesion to move water up against gravity without using energy

Process: 1) Cohesion: water forms a column. 2) Adhesion: water sticks to vessel. 3) Transpiration: water evaporates from leaf.

Question 13

What does an acid release when placed in water? A base?

Answer 13

• Acid: releases H+ (hydrogen ions)
• Base: releases OH- (hydroxide ions)

This is fundamental in understanding acid-base chemistry.

Question 14

What is pH a measure of?

Answer 14

pH is a measure of the amount of H+ (hydrogen ions)

pH scale is crucial for understanding acidity and basicity.

Question 15

List the pH range for things that are acidic, basic, and neutral.

Answer 15

• Acid: 0-6.9 (e.g., lemon, pineapple)
• Base: 7.1-14 (e.g., soap, bleach)
• Neutral: 7 (e.g., water)

Understanding pH is essential in various scientific fields.

Question 16

What are the general characteristics of an acid? A base?

Answer 16

• Acid: sour, corrosive
• Base: bitter, slippery

These characteristics help identify substances in everyday life.

Question 17

Would an acid that has a pH of 1 have more or less hydrogen ions in solution than an acid that has a pH of 4?

Answer 17

A pH of 1 has more hydrogen ions than pH 4

As pH decreases, acidity increases.

Question 18

What are some examples of common household acids and bases?

Answer 18

• Acids: battery acid, stomach acid, lemon juice
• Bases: seawater, baking soda, household ammonia

These substances are commonly encountered in daily life.

Question 19

Do acids and bases become stronger or weaker as they move away from neutral?

Answer 19

As they move away from neutral (pH 7), they become stronger

The strongest acid has a pH of 0 and the strongest base has a pH of 14.

Question 20

How much more acidic is a pH of 2 compared to a pH of 4?

Answer 20

100x more acidic

Each pH unit represents a tenfold change in acidity.

Question 21

What are buffers and why are they important?

Answer 21

Buffers are mixtures of chemicals that can react with acids or bases to keep pH in a particular range

They are crucial for maintaining homeostasis in biological systems.

Question 22

What is the pH of blood? What happens if the pH goes above or below it?

Answer 22

pH of blood is 7.4; if it goes above 7.8 or below 7.0, you die

This highlights the importance of pH regulation in the body.

Question 23

How do you write a chemical equation?

Answer 23

Reactants are on the left and products are on the right

This format is essential for understanding chemical reactions.

Question 24

Why do equations have to be balanced?

Answer 24

Law of conservation of mass states that matter cannot be created or destroyed

This law necessitates that both sides of the equation have the same number of each type of atom.

Question 25

What is **activation energy**?

Answer 25

The minimum amount of energy required for a chemical reaction to occur ## Footnote This concept is vital in understanding reaction kinetics.

Question 26

What is the difference between **exothermic** and **endothermic reactions**?

Answer 26

* Exothermic: releases energy * Endothermic: absorbs energy ## Footnote These reactions have different energy profiles.

Question 27

What is the **lock and key** model used to describe?

Answer 27

A chemical reaction that uses an enzyme, where a substrate fits into an enzyme's active site ## Footnote Lock: enzyme active site; Key: Substrate (reactant).

Question 28

Can **enzymes** be reused after they’ve been used in a chemical reaction?

Answer 28

Yes ## Footnote This property makes enzymes efficient catalysts.

Question 29

How can an enzyme become **denatured**?

Answer 29

By an increase or decrease in temperature or pH away from optimal ## Footnote A denatured enzyme cannot be used or repaired.

Question 30

What is an enzyme’s **role** and how does it function?

Answer 30

To speed up chemical reactions by lowering activation energy ## Footnote Enzymes are crucial for metabolic processes.

Question 31

What can influence an enzyme’s **activity**?

Answer 31

* Speed it up: Increase enzyme concentration, increase substrate concentration, optimal temperature, optimal pH * Slow it down: Decrease enzyme concentration, decrease substrate concentration, increase or decrease temperature from optimum, increase or decrease pH from optimum ## Footnote These factors are essential for enzyme regulation.

Question 32

What makes a molecule **organic**?

Answer 32

All organic molecules contain carbon ## Footnote This definition is fundamental in biology.

Question 33

How many bonds can a **carbon atom** form with other atoms?

Answer 33

4 covalent bonds ## Footnote This property allows for diverse organic compounds.

Question 34

Know the function and examples of **carbohydrates**, **lipids**, **proteins**, and **nucleic acids**.

Answer 34

* Carbohydrates: quick energy and structural support (e.g., glucose, starch) * Lipids: long-term energy storage (e.g., fats, oils) * Proteins: structural support and enzymes (e.g., enzymes, muscles) * Nucleic acids: hereditary material (e.g., DNA, RNA) ## Footnote Each macromolecule plays a unique role in biological systems.

Question 35

What atoms are present in each of the **macromolecules**?

Answer 35

* Protein: C, N, O, H, S * Lipid: C, H, some O * Carbohydrate: C, H, O (in a 1:2:1 ratio) * Nucleic acid: C, N, O, H, P ## Footnote Understanding the composition of macromolecules is essential in biochemistry.

Question 36

Which atom is unique to **nucleotides**? **Amino acids**?

Answer 36

* Amino acids: Sulfur (S) * Nucleotides: Phosphate (P) ## Footnote These unique atoms are key to the structure of these macromolecules.

Question 37

What ratio are carbon, hydrogen, and oxygen found in **carbohydrates**?

Answer 37

1:2:1 ## Footnote Example: C6H12O6 shows the typical ratio in simple sugars.

Question 38

What is the difference between a **monosaccharide**, **disaccharide**, and **polysaccharide**?

Answer 38

* Monosaccharide: One sugar ring (e.g., Glucose) * Disaccharide: Two sugar rings (e.g., Sucrose) * Polysaccharide: Multiple sugar rings (e.g., Plant: cellulose, starch; Animal: glycogen, chitin) ## Footnote These classifications are important in understanding carbohydrate structure and function.

Question 39

What is the difference between a **saturated** and an **unsaturated fatty acid**?

Answer 39

* Saturated: only single bonds between carbons (from animal sources) * Unsaturated: one or more double bonds between carbons (from plant sources) ## Footnote This distinction affects the physical properties of fats.