Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Biology > Biological Molecules > Flashcards

Biological Molecules Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

Reaction from monomer to polymer

A

Condensation reaction, a water molecule is produced and monomers are left covalently bonded.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Reaction from polymer to monomer.

A

Hydrolysis reaction, requires the addition of a water molecule which splits into OH and H to join with monomer and break their covalent bond

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the 2 isomers of glucose

A

Alpha glucose
Beta glucose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is an isomer?

A

Compound with the same formula but different atomic arrangement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the general formula for monosaccharides?

A

(CH2O)n

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

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

A

Mono= one chain of sugar
Di- two chains
Poly= many chains

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are reducing sugars?

A

Sugars that give up electrons to the reagent used in testing for sugars, causes a colour change

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the test for reducing sugars?

A

Method
1. Crush food sample
2. Add distilled water
3. Add a similar volume of Benedict’s reagent
4. Put into a water bath to heat up
5. Positive result= colour change
Blue= none
Green/ yellow= traces
Orange= moderate amount
Brick red= large amounts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is maltose?

A

2 glucose molecules bonded together (alpha glucose)
Found in food, natural
Cannot be absorbed into blood

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is sucrose?

A

1 glucose, 1 fructose bonded together
Bonded by a glycosidic bond between the two monosaccharides

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is lactose?

A

1 galactose and 1 glucose boned together

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are 5 examples of monosaccharides?

A

Glucose
Fructose
Galactose
Deoxyribose
Ribose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is always released when two monosaccharides are bonded together?

A

H2O, water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are non-reducing sugars?

A

Ones that dont really give up their electrons to reduce the copper sulphate in the Benedict’s solution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the test for non-reducing sugars?

A
  1. Add 2cm3 of your sample to a test tube with 10 drops of HCL
  2. Heat to boiling point for 2 mins (the acid causes the hydrolysis)
  3. Add sodium hydrogen carbonate spatula by spatula until the fizzing stops to neutralise the acid (Benedict’s doesn’t work under acidic carbonate)
    Test with PH paper to confirm it is neutral/ slightly alkaline
  4. Retest with Benedict’s to observe a colour change
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is starch?

A

Store of energy in p;ants and main energy source in humans diet

17
Q

What are the two types of starch?

A

Amylose
Amylopectin

18
Q

What is the structure of starch?

A

Made of alpha glucose monomers bonded through condensation reaction. (h2o emitted)
Glycosidic bonds between oxygen atoms
Helical structure by hydrogen bonds of hydroxyl groups

19
Q

How does the structure of starch lead to its function?

A

-Large molecule= insoluble
Doesn’t affected water potential, doesn’t allow water into the cell (pressure)
Cannot diffuse out of cells (made inside the cell)
- Helix structure= insoluble
Lots can be stored within chloroplasts which is a small place
-Hydrolysed into alpha glucose
Easily transported through the organism
Readily used when needed for respiration
-Branched amylopectin structure= many ends to the molecule
Lots of areas for enzymes to act and hydrolyse the polymer simultaneously and release glucose quickly

20
Q

Test for starch

A

Add food sample to a test tube
Add a few drops of iodine
Contains starch= blue/black colour change

Limitation= doesn’t indicate the amount of starch in the sample

21
Q

Structure of glycogen

A

Similar structure to starch but smaller chains with more branches
Made of alpha glucose monomers bonded through condensation reactions

22
Q

How does the structure of glycogen lead to function?

A

-Large molecule= insoluble
Doesn’t affected water potential, doesn’t allow water into the cell (lysis)
Does not diffuse in and out of cells
-compact
Lots can be stored within a small space (muscles and liver)
-hydrolysed into alpha glucose
Easily transported throughout organism
Readily used when needed for respiration
-highly branched structure- many ends to the molecule
Lots of area for enzymes to act and hydrolyse the polymer simultaneously and release glucose quickly, more important to animals than plants.

23
Q

What is cellulose?

A

Formed of beta glucose where alternating monomers are upside down to facilitate the glycosidic bonds
No coils or branches, it forms long straight molecules that run parallel to each other, held in place with hydrogen bonds
Molecules held together by hydrogen bonds, forming cross bridges

24
Q

What is the structure of cellulose?

A

Linear, unbranching chains are held together with hydrogen bonds
Chains group together to form microfibrils, those are arranges in alternate directions to give strength to cell walls.

25
Q

What are lipids?

A

Contain C, H and O
Insoluble in water
Soluble in organic solvents, such as acetone and alcohol
Fats solid at room temperature, oils liquid at room temp (triglycerides)

26
Q

Main functions of lipids

A

Energy source- oxidised to release more than twice the energy stored in carbohydrates
Insulation- poor conduction of heat to insulate heat and also to insulate electrical impulses in nerve cells (myelin sheath)

Protection- physical protection around certain organs
Waterproofing- insoluble property used in plant waxy cuticles and animal sebaceous glands

27
Q

Triglyceride structure

A

One glycerol molecule bonded to three fatty acid molecules
Ester bond (forms between an alcohol and an acid) forms from a condensation reaction also forming a water molecule from each bond (total of 3)

28
Q

Variation in triglycerides

A

Glycerol molecule is always the same in a triglycerid3
Over 70 different fatty acids
You can form 3 of the same fatty acids forming a simple trig.
Varying properties of trig are a result of the combination of fatty acids

29
Q

What is a saturated fatty acid?

A

No double carbon bonds, bonded to as many H atoms as possible already

30
Q

What is a monounsaturated fatty acid

A

One double bond between carbons

31
Q

What is a polyunsaturated fatty acid?

A

Multiple double bonds between the carbons

32
Q

Properties of lipid structure

A

-high energy source
High ratio of C-H bonds to C atoms
-good storage molecule
Low mass compared to energy stores in bonds means more energy can be stored in a small volume, most beneficial to animals carrying mass.
-insoluble molecules
Large and non-polar, doesn’t affect water potential of cells or osmosis
-important source of water
High ratio of H to O atoms, releasing water when oxidised, especially important for animals in hot environments

33
Q

What is a phospholipid structure?

A

A glycerol backbone attached to only 2 fatty acids with phosphate group bonded to the other end of the glycerol
Hydrophilic head- phosphate and glycerol, is attracted to water, does mix with fat.
Hydrophobic tail- fatty acids, orientates away from water, can mix with fats.

This is a polar molecule (2 poles behave differently`) and wil position themselves relative to water
Triglycerides are extremely hydrophobic

34
Q

Phospholipids properties

A

Polar molecules interacting with water
-hydrophilic and hydrophobic ends of molecules allow a bilayer to form as the cell membrane, the polarity causes a barrier between the inside and outside of the cell

Can form glycolipids
Sugar can bond to the phospholipid molecule to form a glycolipid on the outside of the cell membrane- helps maintain membrane stability and used in cell recognition

35
Q

Test for lipids

A
  1. Label the test tubes suitably for the foods to be tested
  2. Chop solid food on a tile or grind with a pestle and mortar
  3. Add the food to a labelled test tube to a depth of about 1cm. For olive oil add 2 drops.
  4. Add 3cm^3 of ethanol to each test tube
  5. Put a clean bung into each test tube and shake carefully at least 10 times. This will help nah lipids deissolve in the ethanol
  6. Allow time for food particles to settle. You may proceed when the ethanol above the food has cleared.
  7. Use the wash bottle to dispense about 3cm of distilled water into the test tubes.
  8. Observe and note any changes
36
Q

What are monomers

A

Small units which are components of larger molecules

37
Q

What is a polymer

A

Molecules made from many monomers joined together

Biology (7 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions