Module 2 Flashcards
(83 cards)
Three components of the cytoskeleton
Microfilaments- contractile fibres formed from actin, responsible for cell movement
Microtubules- globular tubular proteins used to form a scaffold-like structure that determines the shape of the cell
Intermediate fibres- give mechanical strength to cells
Differences between prokaryote and eukaryote
Pro=no nucleus, circular DNA, non membrane bound organelles, peptidoglycan cell wall
Euk= nucleus, linear DNA, membrane and non membrane bound organelles, chitin (f) cellulose (p) cell wall, no cell wall (a)
What elements do carbohydrates have
C H O
What elements do lipids have
C H O
What elements do proteins have
C H O N S
What elements do nucleic acids have
C H O N P
Describe ice
(less dense) so molecules spread out Lattice Ice forms insulating layer Water below doesn’t freeze Many hydrogen bonds between molecules High specific heat capacity
Describe the structure of ice
Between O and H (of adjacent molecules)
Between electropositive and electronegative
Water molecule is polar
Explain the importance of water being a solvent
medium for (metabolic) reactions Transport in the xylem and phloem Organisms can absorb minerals Able to dilute toxic substances *NOT NUTRIENTS*
Describe the test for reducing sugars using colorimeter
Use known concentration of reducing sugars Heat with Benedict's solution Changes to brick red Reading of transmission Calibration curve
Describe amylose
1-4 glycosidic bonds
Helix
More compact
Less soluble
Describe amylopectin
1-4 and 1-6 glycosidic bonds
Branched (lots of free ends)
More compact
Less soluble
Describe glycogen
1-4 and 1-6 glycosidic bonds
Highly branched and free ends
More compact
Less space needed for it to be stored
Describe cellulose
1-4 glycosidic bonds (beta glucose molecules)
Alternate beta glucose molecules are turned upside down
Straight chain
Strong and insoluble
Bond of triglyceride
ester
Saturated fatty acids
no double bonds
Unsaturated fatty acids
double bonds
Roles of lipids in living organisms
thermal insulation, energy store, protects vital organs, buyout, water proofing
Roles of lipids in cells
electrical insulation in myelin
hormones
Describe the primary structure of. a protein
Peptide bonds between amine and carboxyl group
H combines with OH
Condensation reaction
Covalent bond
Describe the secondary structure of a protein
hydrogen bonds form causing either an alpha helix or beat pleated sheet
Describe the tertiary structure of a protein
Some R groups attract/repel
Disulphide bonds between cysteine
Hydrogen bonds
Ionic bonds between oppositely charged R groups
Hydrophilic R groups on the outside of the molecule
Hydrophobic R groups on the inside of the molecule
Describe the quaternary structure of a protein
same interaction in tertiary, but between protein molecules
Describe globular proteins
compact, water soluble, normally spherical