BIOCHEMISTRY: Part 1

What is a Polar Molecule?

It is a covalent compound that shares its electrons unequally between the hydrogen atoms and the oxygen atom. This results in a molecule with a partial positive charge on one end and a partial negative charge on the other.

Water is termed this due to its charged ends

Polar Covalent

What is Universal Solvent

The term given because it can dissolve large number and variety of materials. Both organic and inorganic and as well as polar and ionic, substances due to its polarity.

What is Hydrogen Bond?

An attraction between a positively charged hydrogen atom and a negatively charged atom, which is not a true chemical bond.

What is Cohesion?

When the property of water molecules sticking to one another as they form hydrogen bonds with itself.

What is Adhesion?

When the property of water molecules sticking to other surfaces (ex. such as plant xylem tubes)

Water molecules stick to one another, which allows for?

• Surface Tension

• Transpiration

• Circulation

What is Surface Tension?

The ability of water to support small objects caused by hydrogen bonds between neighbouring molecules forming a “film” at the surface.

What is Transpiration?

The movement of water upward against gravity, facilitated by cohesion and adhesion (ex. in plant xylem tubes)

What is Circulation?

The ability for water to “climb” structures and flow through tubes

What is the term for the amount of energy needed to raise the temperature of 1 kg of a substance by 1°C

Specific Heat Capacity

What is the Specific Heat Capacity of pure water?

_{CH20 = 4200J/Kgºc}

Why is water a good insulator?

Because it does not change easily change the temperatures. It also helps organism maintain a consistent internal temperature

Why does water act like a coolant?

When water evaporates, energy is needed to change state. It also allows organisms can lower their body temperature by sweating or panting

How do organism lower their body temperature?

By sweating or panting

Why is water able to serve as a stable habitat for so many organisms?

• Many organisms live in it for part or all of their lives

• Its Specific Heat Capacity keeps temperatures stable

How do fish and reptiles utilize water temperature?

They depend on it to regulate their body temperature

Why does water remain liquid under an ice cap?

Because has a low density

How does water participate in general biological chemical reaction?

• Most reaction occur in an aqueous environment

• Some reaction produce water as a byproduct

• Other reaction use water directly as a reactant

What is Hydrolysis?

A chemical process in which compounds are cleaved into two parts by the addition of a molecule of water

What happens to the water molecule during hydrolysis?

• One fragment of the broken compound gains a hydrogen ion (H+)

• The other fragment collects the Hydroxyl group (OH-)

The reverse of Hydrolysis

Dehydration Synthesis

What happens during a Dehydration Synthesis reaction?

Two molecules combine to form a larger molecule while removing the a water molecule

What is Dissociation?

A usually reversible process facilitated in water where molecules or ionic compounds are separated into smaller particles

What is a buffer?

A chemical that resists changes in pH, which helps animals maintain an optimal pH

What two ion can water split into?

Hydrogen ions (H+) and hydroxide ions (OH-)

Why is maintaining an Optimal pH critical for living organism?

pH stongly impacts the activity and function of enzymes

Why is the transparency of water biologically important?

It allows sunlight to transmit through it

What process does water transparency permit in aquatic ecosystem?

Photosynthesis

What is an atom?

The basic building blocks of mattter, where all atoms of a given element have the same number of protons and electrons

What do atoms form when they react with one another?

Compounds

All living animals are composed of which two types of compounds?

Organic and Inorganic compounds

What defines an Organic compound?

It contains Carbon, Hydrogen, and usually Oxygen

(ex. C3H6, CH4, an C6H12O6)

What defines an Inorganic compound?

A compound that does not contain both carbon and hydrogen

(ex.H2O, NaCl, and CO2)

What are the four most common elemnts in living things?

Carbon (C), Hydrogen (H), Oxygen (O), and Nitrogen (N)

What percentage of living matter is Oxygen (O)?

65%

What percentage of living mater is Carbon (C)?

18.5%

What percentage of living matter is Hydrogen (H)?

9.5%

What percentage of living matter is Nitrogen (N)?

3.3%

This Element is found in some amino acids and proteins, it is also needed to build and repair DNA

Sulfur (S)

This element is found in ATP, DNA/RNA and cell membrane?

Phosphorus (P)

This element is needed for nerve, bone, and muscle cell functioning?

Calcium (Ca)

This element is found in hemoglobin and is essential for oxygen transport in blood?

Iron (Fe)

This element is needed for nerve and muscle cell function?

Sodium (Na)