Biology 1

Large, Complex molecules with a structure based on a carbon atom backbone

Organic molecules

Small, simple molecules with a lack (one or a few) carbon molecules

Inorganic molecules

Name 4 types of bonds in biological molecules

Ionic, Covalent, Hydrogen, Van der Waals interactions

What bond involves transfer of electrons?

Ionic

In an ionic bond, what causes attraction ?

Difference of charges

In water, oxygen is more… than hydrogen.

Electronegative

What bond forms between non polar molecules that are very close together?

Van der waals interactions

In water, there is a partial … charge on oxygen and partial … charge on hydrogen.

negative

positive

Hydrogen bond occurs between…?

molecules

Hydrogen in a hydrogen bond is attracted to electro… atoms like …?

negative

O or N

Why is water a polar molecule if it has no net charge?

Unevenly distributed charges

Attraction between H20 and polar substances is called … force

adhesive

Why does water have a high specific heat

Large amounts of heat energy is required to break H bonds between H20 molecules.

Surface tension produced by attraction between water molecules is called … force

adhesive

What is high heat of vaporization?

the quantity of heat that a liquid must absorb for 1 g of it to be converted from liquid to solid

How does water act as a solvent to dissolve ionic compounds and poler molecules?

water’s partial charges attracts ions

water forms hydrogen bonds around polar molecules

Acid is a substance that (…) H+ concentration in a solution

increases

Base is a substance that (…) the H+ concentration in a solution

reduces

What is a substance that minimizes the changes in pH?

Buffer

Explain how high heat of vaporization of water works

H20 molecules are held by hydrogen bonds

High energy is used to break H bonds so that they can escape as gas

In a solid state, water forms …? (Hint: density, structure)

Crystalline lattice

Explain evaporative cooling

H bonds in the water break

Heat is taken with them

Temperature lowers

In water’s solid state, a crystalline lattice is formed because molecules can bond to a maximum of … neighbours

4

At 4 degrees Celcius, water has it’s … density

highest

How can organisms still live in oceans and lakes during winter?

Water at the surface freezes

Forms an ice sheet at the surface

Ice sheet insulates the water below

Prevents water from freezing solid

State the 6 properties of water

Cohesion, adhesion

High: SHC, Heat of vaporization

Density

Solvent

Viscosity

Water can dissolve … and … substances easily

Ionic

Polar

How does water have low viscosity? (Viscosity- property of being thick or sticky)

Small size

H bonds easily broken (and reformed)

(molecules can slide over each other)

A person cannot survive drastic change in pH of blood. What component in blood prevents this?

Buffer - Carbonic acid

What happens to carbonic acid when pH of blood increases?

H2CO3 → H+ + H Co3-

dissociate to for, H+ and bicarbonate ion

What happens when blood pH decreases?

(Hint: H and bicarbonate ion)

H+ and H CO3- combine to for, H2CO3 (carbonic acid)

What happens to a buffer when pH increases?

accepts H+

What happens to a buffer when pH decreases?

donates H+

What is the role of carbonic acid / buffer in blood ?

Maintains constant blood pH

reveives extra H+ or

What is the function of mineral salts?

Regulate body processes

( Ca and Phosphorous- bones

Ca - muscle contractions

Na and K- nerve impulse transmission

Carbon can form multiple bonds with … (strong bonds)

Hint: 3

C O N

Carbon can form … covalent bonds

4

Carbs / saccharides consist of … at a … ratio

C H O

1:2:1

(CARB) What is the name and property of this functional group?

hydroxyl

polar

(CARB) What is the name and characteristic of this functional group?

methyl

nonpolar

(CARB) What is the name and characteristic of this functional group?

carbonyl

polar

(CARB) What is the name and what are the characteristics of this functional group?

Carboxyl

Charged, acidic (can release H+ ions into solution)

(CARB) What is the name and what are the characteristics of this functional group?

Amino

Charged, basic (can remove H+ from solution)

(CARB) What is the name and what are the characteristics of this functional group?

Phosphate

Charged, acidic (can release H+ into solution

What are the 3 types of isomers?

Structural, geometric, optical

What are polymers?

Long chain molecules

Made of many similar identical units (monomers)

joined by covalent bonds

How are polymers synthesised?

Condensation/dehydration of monomers

Enzymes remove -OH from one molecule and H from another, release water

How are poly,ers broken down?

Hydrolysis

What are the functions of carbohydrates

Energy

Structure component in cells

(monosaccharide)

… ring

Pyranose

(monosaccharide)

… ring

furanose

…-glucose

alpha

…-glucose

beta

(carbohydrates)

properties : sweet tasting, water soluble, can form crystals, reducing sugars

monosaccharide

the carbonyl group at the end is a(n) … and the sugar is a(n)

aldehyde

aldose

this position of carbonyl group is a(n) … amd the sugar is a(n)

ketone

ketose

The ability of sugar to reduce copper valency in benedicts solution

reducing sugar

when the sugar forms a ring, the aldehyde/ketone becomes the … carbon that is … reactive than otjer carbons in the sugar

anomeric

(to open the double bond, a free -OH group is attatched)

all monosaccharides are reducing sugars because of presence of free …

OH

Disaccharides are two monosaccharides joined to together by … bond

glycosidic bond

malt sugar (a reducing sugar)

milk sugar, reducing sugar

table sugar, found in plants, reducing sugar

Is this a reducing sugar? Why?

No

Both anomeric carbons are involved in glycosidic bond

(No free OH)