2a. Biological Molecules: Water & Carbohydrates Flashcards
Water is a _____ ______ of cells.
What is a water molecule made up of?
Does water have an overall charge?
However, the Oxygen atom in Water is _____ _____, while the Hydrogen Atoms are slightly ______
Dipolar meaning?
Is Water Dipolar?
The _____ pole of one water molecule is ______ to the negative ____ of another.
Major Component
2 Hydrogens, 1 Oxygen = H2O
No overall charge
1. slightly negative
2. positive
containing both positive and negative poles
Yes, O (negative) h2 (positive)
1. positive
2. attracted
3. pole
What is a Hydrogen bond?
Is a Hydrogen bond a strong bond?
Attractive force between the opposite charges in water
No it is a relatively weak bond, 1/10th a covalent bond
Why does water have so many unusual properties?
What are the 5 major properties of water?
Although Hydrogen bonds are weak, a huge number of them in water, would have a significant force.
1. High specific heat capacity
2. High latent heat of vaporisation
3. Strong Cohesion and surface tension
4. Solvent
5. Metabolite
What is the biological importance of “high specific heat capacity” in water?
How is this important for aquatic and subcellular activity?
- allows water to act as a buffer against sudden temperature changes
- if water is a buffer against sudden temperature hanged it allows aquatic life to survive in hot temperature and cold temperature external conditions as water wouldn’t have a huge change in temperature.
What is the biological importance of “latent heat vaporisation” in water?
How is this helpful for the human body?
- needs a lot of energy to make water vaporise
- sweating would therefore require more energy to complete, therefore large amounts of energy are transferred from the body as thermal energy which reduces body temperature
What is the biological importance of “strong cohesion and surface tension in water”?
How is this helpful for plants and some insects?
- Large amount of weak hydrogen bonds would create a large force since there are lots of H bonds, this means there would be strong cohesion and surface tension on water
- biologically the creation of surface tension due to the strong collection of Hydrogen bonds, can create a layer of skin, which could allow insects and other lightweight life to live an move on water
- in plants this allows water to be pulled up the Xylem in CONTINUOUS COLUMNS, since large amount of hydrogen bonds keep water molecules together with significant force
What is the biological importance of “Solvent” in water?
- in cells water is a main part of the cytoplasm,
meaning that metabolic reactions can happen in solution - metabolic reactions happen FASTER in solution
which increases efficiency - as well as this substances are easily transported in water around an organism
What is the biological importance of “Metabolite” in water?
- metabolite is used in metabolic reactions such as “photosynthesis and hydrolysis”, as well as being formed in condensation
What is the Specific Heat Capacity Definition?
Amount of energy (Joules), required to change 1kg of substance temperature by 1 degrees Celcius
What is pure waters specific heat capacity?
4190
What is a polymer?
Give two examples of Biological Molecules that are polymers:
How are polymers formed? (hint: type of reaction)
How are Monomers formed from Polymers?
A molecule made up of many monomers (repeating units) joined together
- proteins
- carbohydrates
Condensation Reaction
Hydrolysis Reaction
What are Monosaccharides?
Give two properties of Monosaccharides:
Name 3 Monosaccharides:
What is the general formula of Monosaccharides?
What are the formulas of glucose, fructose and galactose?
monomers/basic molecular units of which carbohydrates are composed
-soluble
-sweet
-glucose
-fructose
-galactose
CnH2nOn
C6H12O6
Glucose is a ____ sugar (hint: numerical value)
What is glucose a product of?
What is glucose a substrate in?
What are the two types of glucose?
What are the differences between Alpha and Beta glucose?
hextose
Photosynthesis
respiration
Alpha Beta
On Carbon-1 of alpha glucose the Hydrogen is facing upwards and the hydroxyl (OH) is facing downwards, but in beta Carbon 1 the Hydroxyl (OH) is facing upwards and the Hydrogen is facing downwards
What is glucose a product of?
Photosynthesis
What is glucose a substrate in?
respiration
What are the two types of glucose?
Alpha
Beta
What are the differences between Alpha and Beta glucose?
On Carbon-1 of alpha glucose the Hydrogen is facing upwards and the hydroxyl (OH) is facing downwards, but in beta Carbon 1 the Hydroxyl (OH) is facing upwards and the Hydrogen is facing downwards
Monosaccharides can be linked to form _____
Polymers
What are disaccharides?
Two monosaccharides joined together (di-meaning 2)
Are disaccharides polymers?
No
What type of reaction is it when two monosaccharides join together?
Condensation
What type of bond is formed when two monosaccharides join together?
Glycosidic
What products are formed when two monosaccharides join together?
Disaccharide + Water
Why is water formed when two monosaccharides join together?
Due to it being a condensation reaction
What type of bond is a glycosidic bond?
Covalent
What are the 3 disaccharides?
- maltose
- lactose
- sucrose
How is maltose formed? (word equation)
glucose + glucose –> maltose + Water
alpha + alpha
How is sucrose formed? (word equation)
glucose + fructose –> sucrose + Water
How is lactose formed? (word equation)
glucose + galactose –> lactose + Water
What is the formula of disaccharides?
Why?
C12H22O11
2 hydrogens 1 oxygen used for water
Reverse reaction of two monosaccharides?
Hydrolysis
What type of glycosidic bond is formed from two monosaccharides forming a disaccharides?
Why?
1-4, the Carbon 1 and Carbon 4 from other molecule both bond to Oxygen
What are Polysaccharides?
Chains of many monomers of A-glucose or B-glucose
How are Polysaccharides formed?
Condensation
What are the 3 Polysaccharides?
- starch
- glycogen
- cellulose
Of the 3 Polysaccharides, which are used in animal cells or plant cells?
- Starch (plant)
- Glycogen (animal)
- Cellulose (plant)
What are Starch and Glycogen monomers made from?
A-Glucose
What are Starch and Glycogen made for?
For energy storage, in plant and animals
What monomers are Cellulose made from?
B-Glucose
What is Cellulose made for?
Makes plant cell walls and are used for STRUCTURE
____ Grains are used for _____ _____ in plants
Starch
Energy Storage
How many polymers is starch made from?
Which polymers is starch made from?
2
-Amylose
-Amylopectin
What is Amylose’s definition and function?
Amylose is a helical (helix) chain used to store large amounts of glucose molecules in a small space since it is compact
What glycosidic bonds do Amylose contain?
What is Amylopectin definition and function?
1-4
Amylopectin is branches, which allows amylopectin to be hydrolysed by amylase enzymes, to form maltose, which can be further broken down into glucose, to be used for quick respiration.
Why does the branching of Amylopectin allow faster respiration?
Since it is branched, this means amylase enzymes can hydrolyse from different branches rather than hydrolysing linearly, which mean that the hydrolysis would be faster.
This allows maltose to be formed quicker, which is further broken down into glucose for fast respiration
What is Amylopectin structure?
What type of glycosidic bond does Amylopectin have?
It is coiled until the branching occurs
1-4 for coils
1-6 for branching
What is the difference between Starch’s structure and Glycogen’s structure?
-Glycogen contains more branches
Both Glycogen and Starch are well suited to being energy storage molecules:
Why? (hint- 4 bullet points)
- Both helical (coiled), meaning they can store large amounts of glucose molecules in a small space, because it is compact
- Both have branched meaning enzymes can hydrolyse them at different “ends” quickly, to break down into glucose for respiration
- Large and insoluble so cannot diffuse out of cells in which they are stored
- Insoluble so have no osmotic effects
When two monomers of cellulose link together what needs to be done to the structure of one of the monomers?
Why?
- Molecule on left (beta glucose) needs to be flipped
- So Hydroxyl (OH) groups are close enough together to join together with a glycosidic bond
Describe Cellulose’s structure:
How does this make Cellulose suited to its function?
- Made up of long straight unbranched chains of Beta-Glucose, due to every other glucose molecule flipping
- These chains run parallel to each other, which allows cross-links between chains through Hydrogen bonds
- Many Hydrogen bonds are COLLECTIVELY strong, and since there are many monomers, this creates high TENSILE strength in the cell wall, which helps strengthen/create rigidity in the cell, as well as prevent osmotic lysis
- These cross linked chains are grouped to form microfibrils, which then group to form macrofibrils, providing even more strength
Which of the 3 polymers are inert?
Which of the 3 polymers are soluble?
All of them
None of them
What bonds are present in glycogen + starch?
What bonds are present in Cellulose?
1-4 glycosidic bonds
1-6 glycosidic bonds
1-4 glycosidic bonds
Hydrogen bonds
Describe the Test for Stach:
- Add iodine solution to sample
- If Starch is present, orange/brown –> blue/black
Describe test for Reducing Sugars:
- Add Benedict’s solution to sample in a test tube
- Shake Test Tube
- Heat in Water Bath to 95 degrees Celcius
- If reducing sugar is present the sample should turn red
- However it could turn Green (very low conc), Yellow (low conc), orange (medium), red (high)
Describe Test for non-reducing sugars:
- Complete Benedict’s test for REDUCING SUGARS, if no colour change reducing sugar could be present
- Boil fresh sample with Dilute Acid e.g HCl
- Neutralise the acid
- Re-heat sample with Benedict’s Solution, if sample now turns red, (or green/yellow/(orange/brown), then non reducing sugar was originally present in the sample
Why should sample be BOILED with dilute acid in non reducing sugar test?
For “Acid Hydrolysis” to occur, where the glycosidic bond between the monomers break, leaving just the monosaccharides
Why should the boiled acidic sample be neutralised in non reducing sugar test?
Since Benedict’s doesn’t work in acidic conditions
What are 3 issues with Benedict’s test?
- non-specific
- subjective
- test is qualitative, (no numerical value produced)
What can be used to find specific sugars?
What can be used to quantify results from reducing/non-reducing sugar tests?
biosensor
colourimeter
___ ____ occur in solution in the ____ and ___ ____ of organisms, some in high ______ and some in low _____
- inorganic ions
- cytoplasm
- bodily fluids
- concentrations
What does the Hydrogen Ion do?
What does the Sodium Ion do?
What does the Phosphate ion do?
What does Iron Ion do?
Affects pH levels
Involved in the absorption of glucose and Amino Acids, in the small intestine
Component of DNA, ATP and Phospholipids
Component of haemoglobin in red blood cells
How to work with Calibration Curves Method?
- Make up a dilation series of solutions of different known concentrations
- Have a set volume of each solution
- Complete benedict’s
- Place sample’s in colourimeter tubes and measure absorbance
- Plot on graph and draw line of best fit (calibration curve
- Then complete Benedict’s and Absorbance test on unknown glucose conc solution and use calibration curve to estimate concentration of the unknown solution
What is the x-axis and y-axis of the Calibration Curve Graph?
x-axis: concentration (independent)
y-axis: Absorbance (dependent)
What is the formula for Calibration Curve values:
C1 x V1 = C2 x V2
C1 = stock solution concentration
V1 = Volume of diluted values
C2 = diluted solution concentration
V2 = V1 + Volume of water
