MUST LEARN Flashcards
Difference in structure/roles between globular and fibrous proteins
Fibrous: structural roles
-elastic, tough , elongated, flexible, cannot stretch
-insoluble
Globular: metabolic roles
-spherical, tertiary structure, contain prosthetic group
-soluble
What makes a protein conjugated
Contains a prosthetic group
Function of fibrous proteins
Protection- nails, hair skin
Structure- Connective tissue , bone
Elastic- blood vessels
Contraction- muscles, cytoskeleton
Function of gobular proteins
Catalyse reactions hormones e.g. insulin
Antibodies
Transport substances across cell membranes
Transport substances in the blood, haemoglobin
How does co2 move around the body
5% stays in blood plasma
95% diffuses into red blood cells
15-20% binds to hb, forming carbaminohaemoglobin
75-85% forms carbonic acid, catalysed by carbonic anhydrase
Carbonic acid dissociates into h+ and hco3-
Hco3- moves out of the rbc and cl- moves in due to difference in concentration gradients
H+ is removed by buffers, haemoglobin
oxygen dissociates under h+ influence
Process of active transport
Molecule or ion to be transported binds to receptor in the channel of the carrier proteins on the outside of the cell
On inside ATP binds to carrier protein and is hydrolysed into ADP + phosphate
Binding of the phosphate molecule to the carrier protein causes the protein to change shape, opening the inside of the cell
Molecule is realised to the inside of the cell
Phosphate molecule is released from the carrier protein and recombined with ADP to form ATP
carrier protein returns to normal shape
3 domain system
Domains - Bacteria, archea, eukarya
Eubacteria - bacteria
archea bacteria - archea
Protocista, animlia , plantae , fungi - eukarya
Prokaryotae spilt into bacteria and archea
How does
H+ move out of the companion cell
Sucrose move into the companion cell
Sucrose move out
Active transport
Facilitated diffusion
Diffusion
How does amount of h+ effect ph
High concentration of h+ = low ph
Prokaryotae
Unicellular
No nucleus or membrane bound organelles
ring of Naked DNA
Nutrient absorbed through cell wall or photosynthesis
Protoctista
Unicellular membrane bound organelles Chloroplasts Some move by cilia or flagella some don’t Autotrophic- photosynthesis Heterotrophic feeders- ingestion
Fungi - composition
Uni or multicellular Membrane bound organelles Cell wall of chitin No chloroplasts or chlorophyll No locomotion Made from mycelium or hyphae Nutrients from decaying matter, saprophytic feeders Store food as glycogen
Plantae
Multicellular Membrane bound organelles Contain chlorophyll Do not move, apart from gametes Photosynthesis- autotrophic Store food as starch
Animlia
Multicellular Membrane bound organelles Move by cilia or contraction of muscles Heterotrophic feeders Store food as glycogen
What are co factors
Non protien helper component
Transfer atoms or groups from one reaction to another in a multi step pathway
If co factor is organic it is called a co enzyme
Prosthetic groups
Are co factors Tightly bound to certain enzymes, needed to help carry out catalytic function, they form a permeant feature
How does gas exchange take place in insects
Happens through spiracles which are opened and closed by sphincters
When o2 demand is high or co2 levels are high spircales open
Collapsable trachea or air sacs which act as a reservoir, to increase air movement, pumped by the abdomen ( mechanical ventilation)
Interactions in tertiary structure
Further folding or coiling of secondary structures bring different amino acids close enough tighter to interact
Hydrophilic or hydrophobic between r groups - weak
Hydrogen bonds - weakest
Ionic bonds - strong
Disulphides bridges- strongest *( only r groups that contain sulphur)
Quaternary structure
Association of 2 or more or protien subunits
Same interactions as tertiary
Hydrophilic or hydrophobic between r groups - weak
Hydrogen bonds - weakest
Ionic bonds - strong
Disulphides bridges- strongest *( only r groups that contain sulphur)
Diseases caused by viruses
HIV
Influenza
TMV
Diseases caused by fungus
Athletes foot - human
Ringworm- human , patch on skin
Potato blight -plant
Black sigatoka- plant
Diseases caused by protoctist
Malaria- human, spread by female Anopheles mosquito
Diseases caused by bacterium
Tuberculosis
Meningitis
Ring rot
Structures in xylem and phloem
Xylem - lignified, wide lumen , no end walls, no compaion cells, vessels, bordered pits not cytoplasm
Phloem- not lignified ( contain cellulose), lumen not wide, sieve plate elements, companion cells, no vessels , no pits, has cytoplasm
How to observe the gas exchange system of insects or fish
Remove operculum
Cut open exoskeleton
To observe gills or tracheae
Translation
mRNA binds to small unit on ribosome
tRNA molecule with anticodon that is complementary to the start codon carries the corresponding amino acid to the ribosome
Ribosome reads the next triplet of bases on the mRNA
Another tRNA with the complementary rna nucleotides comes and binds with the 3 complementary bases, bring with it an amino acid
RNA polymerase catalyses the formation of peptide bonds between the 2 amino acids
Transcription
DNA helicase unzips the 2 strands of DNA by breaking the hydrogen bonds between the bases
Free rna nucleotides bind the complementary base pairs of the template strand
Thymine is replaced with uracil
Phosphodiester bonds are formed, catalysed by RNA polymerase
mRNA strand detaches from sense strand and leaves the nucleus
