biological molecules Flashcards
What should be identified in strange enzyme diagrams?
Prosthetic groups/cofactors, competitive inhibitors, noncompetitive inhibitors, required materials (i.e: ATP), and conditions needed, justifying all of these.
What do fatty acids contain?
A carboxylic group, so they have oxygen atoms present.
How do you measure lactose concentration using a colorimeter?
Set the colorimeter to 0 using a blank and a red filter, then use known concentrations of lactose produced via serial dilution to construct a calibration curve. Test the unknown sample using the same method and read from the calibration curve to determine the lactose concentration of the unknown solution.
Why can galactose be used as a respiratory substrate?
Its bonds contain energy, which can be broken by respiratory enzymes. Galactose is also soluble, allowing it to move within the cell as the H/OH groups can form H bonds with water.
Why can’t lactose pass through cell membranes?
It is too big to pass between phospholipids and there is only a small concentration gradient. It needs a carrier protein/pump to pass through.
How do polysaccharides form?
They are formed by condensation reactions that create glycosidic bonds between monomers, releasing a molecule of water.
What is the advantage of glycogen as an energy storage molecule?
Glycogen is insoluble, metabolically inactive, compact, and highly branched, allowing for rapid breakdown and release of glucose when needed.
What affects the melting points of fats?
Fats with more double bonds have lower melting points , as they are more kinked , so molecules less uniformly packed together , so lower temp needed for melting
How are DNA nucleotides and ATP similar?
Both have a pentose sugar, adenine as a base, a phosphodiester bond between the sugar and the phosphate, an OH group on carbon 3 of the sugar, and a phosphate group.
ATP has two additional phosphates, deoxyribose replaced by ribose, and an OH group on carbon 2 of the sugar (ribose).
How do you estimate glucose concentration using a calibration curve?
Find the absorbance of the sample using a colorimeter, then from the graph, find the concentration that corresponds to this absorbance by following the absorbance value on the y-axis across to the line of best fit and down to the concentration on the x-axis.
What do glucose and cholesterol have in common?
Both contain carbon atoms, hydrogen atoms, oxygen atoms, and have hydroxyl groups.
Why is cellulose suitable for plant cell walls?
It is insoluble, unreactive/inert, has high tensile strength, and is flexible.
What are the similarities and differences between chitin and glycogen?
Both are polysaccharides composed of 6 carbon sugar monomers with 1-4 glycosidic bonds and CH2OH side groups.
Chitin has -glycosidic bonds, contains nitrogen, has no 1-6 glycosidic bonds, and is not branched.
What is mycoprotein’s fat content compared to animal protein?
Mycoprotein has less fat and less saturated fat than animal protein.
What does a color change from blue to purple indicate in the biuret test?
It suggests that the solution contains protein, as enzymes can be detected by this test since they are globular proteins and water soluble, so can be in solution since their hydrophilic r- groups are on the outside + vice versa
How should a hydrogen bond be represented?
As a horizontal/vertical dashed line between the O on one water molecule and the H on the adjacent water molecule, with the Hs labeled delta positive and the Os labeled delta negative.
What color change does glucose produce in Benedict’s test?
A positive color change is seen as it is a reducing sugar.
What can lead to an overestimation of reducing sugar concentration by Benedict’s reagent?
The presence of other reducing sugars in the sample.
How do you get a 0% transmission reading with a colorimeter for a solution w/ no glucose in?
Use a solution that the Benedict’s test has been done on that has no reducing sugar to calibrate the colorimeter to zero.
Why is using a colorimeter better than a color chart for estimating glucose concentration?
It is more objective/quantifiable, as the instrument has greater precision than a chart.
Why does ice float on water?
Ice is less dense than water as the molecules spread out to form a crystal lattice, providing insulation for the water below.
How do ions interact with water?
Ions are polar charged, and water is also polar, allowing ions to be attracted to and bind with water
tak up minerals+ nutrients from water
What is the significance of plants in yogurt production?
Dairy animals use plants for food, making plants the base of this food chain. Some yogurts also contain fruit and plant flavoring.
What contributes to water’s temperature stability?
Many hydrogen bonds between molecules require a lot of energy to break, resulting in high specific heat capacity (maintain temp) and high latent heat of vaporization.(evaportation)
How does water provide a stable environment for aquatic organisms?
- Water is a thermally stable environment for aquatic organisms,
- so aquatic organisms use less energy on temperature control and the internal temperature of organisms changes only slowly so their enzymes and thus their metabolism functions correctly
What roles does water play in living organisms?
It acts as a medium for reactions, a transport medium, and can dilute toxic substances, allowing for oxygen uptake and waste product removal.