Chapter 4 - Proteins Flashcards
What are the building blocks of proteins?
amino acids
What are dispensable amino acids?
body makes these from other amino acids
What are indispensable amino acids?
the body can’t make these; needed to obtain from the diet
What are conditionally dispensable amino acids?
we can usually makes these, but sometimes some physiological conditions render us unable
Why is tyrosine a conditionally indispensable amino acid for individuals with PKU?
people with PKU lack the enzyme to turn phenylalanine into tyrosine
Which chemical element do proteins contain and provide to the body that fats and carbohydrates can’t?
nitrogen
What is deamination?
the removal of the amine group from an amino acid so it can be broken down for use
What does nitrogen balance measure?
nitrogen balance measures the intake to output of nitrogen which reflects protein status in the body
What does it mean if someone is in zero nitrogen balance?
the body is balancing nitrogen mass without loss or gain of nitrogen
What does it mean to be in positive nitrogen balance?
you have a greater intake than output of nitrogen
Who do we see positive nitrogen balance in?
people recovering from surgery/trauma/illness or those in growth and devlopment
What is negative nitrogen balance?
nitrogen output is greater than intake
What can cause negative nitrogen balance?
inadequate protein intake, or due to burns, trauma, surgery, or old age
What are the five functions of proteins?
tissue building, water and pH balance, energy, metabolism and transportation, and immune system
Why is protein important in tissue building?
protein makes up our organs, skin, hair, and nails
How do proteins affect water and pH balance?
via oncotic (pulling) pressure exerted by albumin (protein), and a unique surface structure that allows them to act as buffers that resist pH changes
How does protein get used for energy? Under what conditions?
we use protein as a very last resort, some amino acids can be made into glucose gluconeogenesis and other to acetyl coA to enter the citric acid cycle
How do proteins help manage metabolism and transportation?
digestive enzymes like salivary amylase, proteases, and pancreatic lipase control metabolic processes; some proteins carry nutrients (lipoproteins carry fats)
How do proteins influence the immune system?
a compromised immune system is a sign of protein deficiency; lymphocytes and antibodies are types of proteins
What is a complete protein food?
a food containing all the amino acids in a sufficient quantity
What is an incomplete protein food?
food that lacks or is deficient in 1 or more amino acid
What are some complete protein food sources?
meat, dairy, egg yolks (most animal sources)
What two plant foods are complete protein sources?
quinoa and soy
What are complementary proteins? List some examples
pairing plant proteins to get all amino acids
legumes + grain, legumes + nuts/seeds
