Genes And Health Flashcards
What removes mucus in the lungs
Cilia on epithelial cells
What is ficks law
Rate of diffusion is directly proportional to
surface area x difference in concentration
———————————————————-
Thickness of exchange surface
Is cystic fibrosis recessive or dominant
Recessive
What effect does the mucus in cystic fibrosis have
Larger diffusion distance
Removes folds - surface area decreases
Trapped pathogens can cause infections
What effect does the mucus in cystic fibrosis have
Larger diffusion distance
Removes folds - surface area decreases
Trapped pathogens can cause infections
Where is mucus created in the lungs
Goblet cells
Describe the structure of phospholipids
Head is hydrophilic so can be exposed to water and tail is hydrophobic so can’t be. This causes the bilayer.
Describe the fluid mosaic model
Fluid - phospholipid bilayer is constantly moving because of the unsaturated fatty acids
Mosaic - proteins scattered through the bilayer
What does cholesterol do in cell membranes
Provides stability
What are glycoproteins and glycolipids for
Communication
Have receptors to detects chemicals from other cells like hormones
How do carrier proteins work
They let substances in - binds and changes shape (energy required) - let’s out the other side
How do Endocytosis and exocytosis work
Vesicles attach to the membrane to transport large bulky molecules in and out of cells
What is the difference between validity, reliability and accuracy
Validity - control variables
Reliability - repeating three times to remove anomalies
Accuracy - method and how close results are to the true value
What is the structure of a protein
Amino group, r group, carboxyl group
What bond joins two proteins
Peptide bonds
What are the four types of bonding in proteins
Hydrogen, disulphide, ionic, hydrophobic interactions
What are the differences and similarities between globular and fibrous proteins
Globular - spherical • fibrous - strands
Globular - soluble because of hydrophilic groups on outside • fibrous - insoluble because they’re hydrophobic on outside
Both are sequences of amino acids joined by peptide bonds
Both have hydrogen bonds
What is a nucleotide made up of
Pentose sugar, nitrogenous base, phosphate
What bonds join two nucleotides together
Phosphodiester bonds
Differences and similarities between RNA and DNA
both have a Penrose sugar
DNA - deoxyribose sugar • RNA - ribose
DNA - ATCG • RNA - AUCG
Both have a phosphate
DNA - double stranded • RNA - single stranded
Describe the process of transcription
• RNA helicase breaks hydrogen bonds and unzips DNA
• free RNA nucleotides line up against template strand via complementary base pairing
• temporary H bonds form
• condensation reactions form phosphodiester bonds between RNA mononucleotides - catalysed by RNA polymerase
• mRNA detaches and exits through nuclear pore into the cytoplasm
Describe translation
• ribosome attaches to start codon on mRNA
• a tRNA molecule carrying a specific amino acid and a complimentary anticodon attaches to the ribosome
• temporary H bonds form
• ribosome moves along to the next codon
• peptide bonds form between new amino acids
• ribosome continues to move along until stop codon is reached
Describe a process carried out my meselson and stahl
• E-coli fed N15 heavy nitrogen
• DNA extracted in a centrifuge
• moved to N14 light nitrogen
• DNA extracted in a centrifuge
• let replicate for one more generation and then extracted again
What are the four types of mutations
Deletion, insertion, substitution, inversion
What is it called when some codons code for the same amino acid
Degenerate code
How does CF affect the digestive system
Pancreatic duct blocked by mucus
Less enzymes in small intestine - nutrients aren’t absorbed - malnourishment
More enzymes in pancreas - break it down - diabetes
How does CF affect the reproductive system
Mucus plug in cervix - sperm cannot reach egg
Sperm duct blocked - sperm can’t leave
What are the similarities and differences between amniocentesis and CVS
Amniocentesis - 15-20 weeks in • CVS - 8-12 weeks in
Both use a needle
Amniocentesis - 1% chance of miscarriage • CVS - 1-2% chance
