BIOLOGICAL MOLECULES

What are the 4 biological molecules?

carbohydrates, lipids, proteins, nucleic acids

what are the chemical elements that make up the biological molecule carbohydrates?

C, H, O

what are the chemical elements that make up the biological molecule proteins?

C, H, O, N, S

what are the chemical elements that make up the biological molecule lipids?

C, H, O

what are the chemical elements that make up the biological molecule nucleic acids?

C, H, O, N, P

What are nucleic acids?

DNA and RNA

What is cohesion and how does it occur?

water molecules can "stick together". They do this by forming hydrogen bonds

does a water molecule have an overall charge?

no

within a water molecule, the oxygen atom is slightly... what?

electronegative

within a water molecule, the hydrogen atom is slightly... what?

electropositive

the nucleus of the oxygen atom in water tends to pull ——- away from the nucleus of each hydrogen atom

electrons

when the nucleus of the oxygen atom in water pulls electrons aways from the nucleus of each hydrogen atom what is created?

a polar molecule

what is a polar molecule?

it has an uneven distribution of charge

how does the oxygen molecule in water form a hydrogen bond?

the oxygen molecule of a water molecule will attract a hydrogen atom of a different water molecule forming a hydrogen bond

one hydrogen bond is weak, but lots of them are...?

strong

draw a water molecule with hydrogen bond

look at notebook

how many hydrogen bonds can each water molecule form?

4

where do many biochemical reactions take place?

cytoplasm

when chemicals dissolve in water they are free to...?

move around & react

what does water attract?

other polar molecules (e.g. sugar) and ions

is water a good solvent?

yes

does water transport substances?

yes

what are 3 examples of when water transports substances?

- blood plasma

- xylem

- phloem

What does water transport in blood plasma?

blood cells, glucose, hormones, etc.

what does water transport in xylem and where are they found?

in plants, water and mineral ions transport

what does water transport in phloem and where are they found?

in plants, transports dissolved sugars

why do both eukaryotic and prokaryotic cells not like temperature changes?

enzymes only work effectively in narrow temperature ranges

( enzymes will denature at high temps)

(enzymes have insufficient KE, resulting is less frequent successful collisions)

why is a large amount of energy needed to raise the temperature of water?

hydrogen bonds restrict their movement

water has a ......... specific heat capacity

high

why are aquatic habitats stable environments for organisms?

temperature is slow to change

why is ice less dense than water?

fewer hydrogen bonds form and water molecules are held further apart

why does ice float on water?

ice is less dense than water

what is the result of ice having an insulating effect?

water below ice does not freeze

what happens when air meets water?

cohesion causes water molecules to form a "skin"

what insect uses the "skin" formed when air meets water to walk on water without sinking?

pond skaters

all mammals and birds maintain their ___ body temp

own

what is the core body temperature in humans?

37 °C

what is an example of a cooling mechanism the human body has if temperature goes above 37°C?

sweating

what happens during sweating?

water evaporates off the surface of the skin - lots of energy is needed to convert water into water vapour

where does the energy needed to convert water into water vapour come from?

excess heat, carried by the blood

what does removing excess heat do in the human body

lowers body temp

water has a high latent heat of vaporisation. what does this mean?

lots of energy is needed to turn water into water vapour

carbohydrates are compounds that contain the element...?

C, H, O

what is the ratio of C, H, O atoms in a carbohydrate?

the number of C and O atoms is always the same, but the number of H atoms is always double

what are the 3 types of carbohydrate?

monosaccharide, disaccharide, polysaccharide

what is an example of a monosaccharide?

glucose

what is an example of disaccharide?

sucrose

what is an example of a polysaccharide?

starch

what does "mono" "saccharide" mean?

mono = one, saccharide = sugar unit

monosaccharides dissolve easily in water to form a .... what?

sweet solution

what does the name of a monosaccharide depend on?

the number of carbon atoms in the molecule

how many carbons does trios have?

3

what is a monosaccharide with 5 carbons called?

pentose

how many carbons do hexoses have?

6

what is an example of a pentose?

ribose

What is an example of a hexose?

glucose

how many carbons does glucose have?

6

what type of monosaccharide is glucose an example of?

hexose

what is the function of glucose?

releasing energy and building larger carbohydrates

how many carbons does ribose have?

5

what type of monosaccharide is ribose an example of?

pentose

what is the function of ribose?

used to make RNA and ATP

how many carbons does deoxyribose have?

5

what type of monosaccharide is deoxyribose an example of?

pentose

what is the function of deoxyribose?

used to make DNA

what is the molecular formula of a hexose?

C₆H₁₂O₆

what is the structural formula of glucose?

a different hexose (e.g. galactose) will have a different arrangement of ...?

atoms

pentose and hexose sugars are long enough to form a ... what?

ring

ring structure are more...?

stable

ABBA

Alpha Below Beta Above

Where is the OH group of carbon 1 in alpha glucose?

below the ring

Where is the OH group of carbon 1 in beta glucose?

above the ring

what type of biological molecule is glucose?

carbohydrate

what type of monosaccharide is glucose?

hexose

what is the formula of glucose?

C₆H₁₂O₆

what type of ring structure does glucose have?

a six-membered ring structure

how are disaccharides formed?

when 2 monosaccharides are bonded together

what is the bond called when 2 monosaccharides are bonded together?

glycosidic bond

how are disaccharides formed, what is the reaction called when a disaccharide if formed, and why is it called that?

- disaccharides are formed when 2 monosaccharides are bonded together with a glycosidic bond

- this is a condensation reaction

- as this reaction releases a water molecule

what are 3 examples of disaccharides?

sucrose, lactose, maltose

what is the disaccharide, sucrose?

cane sugar

which monosaccharides does sucrose contain?

glucose & fructose

what is the disaccharide, lactose?

milk sugar

which monosaccharides does lactose contain?

glucose & galactose

what is the disaccharide, maltose?

malt sugar

which monosaccharides does maltose contain?

glucose & glucose

what are glucose, fructose, and galactose all examples of?

hexoses

what is the molecular formula of hexose?

C₆H₁₂O₆

what is the molecular formula of maltose?

C₁₂H₂₂O₁₁

What is the effect of maltose being made from glucose + glucose monosaccharides

doubles

what type of reaction is the formation of maltose? why?

condensation reaction - loses water molecule

how is maltose formed?

- 2 alpha glucose molecules are joined by a glycosidic bond

- the bond forms between carbon 1 of the first glucose (molecule) and carbon 4 of the second glucose (molecule)

- the bond is called an alpha 1-4 glycosidic bond

what is hydrolysis

molecule of water is added

what is hydrolysis in a disaccharide?

disaccharides can be broken down (hydrolysed) into monosaccharides

what is a polysaccharide made up of?

lots of sugar units joined together by lots of condensation reactions

what are 3 examples of polysaccharides, do they have alpha or beta glucose units, and where are they found?

- starch, lots of alpha glucose units, found in plants only

- cellulose, lots of beta glucose units, found in plants only

- glycogen, lots of alpha glucose units, found in animals only

what is starch?

a polymer of glucose

what are the 2 types of polysaccharides that make up starch?

- amylase

- amylopectin

how are the glucose units joined in amylase

glucose units in amylase are joined by lots of alpha 1-4 glycosidic bonds