CHAPTER 10 Flashcards
What is the essential component of all biological structure and processes?
Proteins
What are some processes of proteins?
impacts cell structures, metabolic reactions, hormonal responses, cell to cell signaling, gene expression, and immune ststem
What results in a nonfunctional or partial functional protein?
DNA mutations
what do genes that encode proteins do?
act as growth hormones, receptors, and transport molecules
What happens if there is a mutation in encode proteins?
can cause dwarfism (lack of protein or non functional protein)
What are the roles of enzymes?
they catalyze cellular biochemical reactions and when linked they form metabolic pathways
Chained reactions of enzymes convert substrate molecules into products. What are substrate and product?
Substrate: specific compound acted on by an enzyme
Product: specific compound that results from enzymatic action and serves as the substrate for the next reaction in the pathway
What happens when a mutation stops the activity of a particular enzyme?
All subsequent reactions in the pathway are shut down
What is a result of a blocked pathway?
Accumulation of compound can be toxic and lead to genetic disorder like PKU and it’s stopped from making essential product
What is the function of PKU.
It is an essential amino acid and a starting point for a network of metabolic pathways.
How does PKU mutation affect an enzyme?
PKU is blocked and phenylalanine hydroxylase convert it to tyrosine which makes PKU accumulate which can lead to intellectual disabilities, jerky movements, epileptic seizures in newborns
What is the treatment for PKU?
Reduction in intake of phenylalanine. Lifelong diet change
What are carbohydrates
Simple sugars and more complex molecules like monosaccharides, disaccharides, polysaccharides
What happens if there is a mutation in the GALT gene?
GALT catalyzes a step in the lactose metabolism pathway so inability to break down galactose means there will be a blocked reaction. It can result in blindness and autosomal recessive disorder
What is the allele for galactosemia?
Allele G+ (100% functional)
Allele g (0% functional)
Allele G^D (50% functional)
An individual needs a total of 0% functionality for galactosemia (2 g allele)
What is lactose
Sugar found in milk. Metabolism begins with breakdown into glucose and galactose, catalyzed by lactase
What happens to activity of lactase as you grow older?
Activity decreases to less than 10% of newborn level in older children and adults
What causes lactose intolerance?
Individuals with low levels of lactase cannot digest the lactose in milk and other dairy products. This is due to a variation in gene expression not a genetic mutation.
What were the first examples of inherited variation in protein structure?
Variations in hemoglobin
What is the effect of the mutant hemoglobin in sickle cell anemia?
It was the first direct proof that mutations result in a change in amino acid sequence in proteins ( cause a genetic disorder)
What is a hemoglobin molecule made up of?
Made up of 4 proteins called globins and each carries an iron containing heme group that binds to oxygen
Sickle cell anemia mutations
Fibers distort and harden the red blood cell membrane, twisting it into a sickle shale
What are the treatments for anemia?
There is no cure but there are medications and procedures to alleviate symptoms (pain relieves and blood transfusions)
How can protein variation affect the body?
It can result in genetic disorders of metabolism and also affect how individuals react to food, anesthetic, prescription drugs, and chemicals in the environment
What is pharmacogenetics?
The study of genetic variations that underlie the differences in individuals responses to drugs
What is eco genetics?
The study of how genetics is related to an individual’s response to environmental substances
