Week 3/4: Acids/Bases, Organic Chem, Cells Flashcards
Why is maintaining pH important?
Regulates chemical environment necessary for optimal cellular function, vital for health (buffer systems).
What 3 mechanisms are responsible in the acid-base balance?
Buffer system (control of H+ ions), respiratory system (CO2 exhalation), renal system (H+ excretion)
What is the function of buffers and what are three important ones?
Buffers are substances that help stabilize and regulate pH and prevent drastic changes. Important = protein, phosphate, bicarbonate.
Give examples of inorganic/organic molecules.
Water, ammonia, acids/proteins, hormones, lipids
Describe aldehydes.
Contain a terminal carbonyl group (C=O) making this part of the molecule reactive, polar, hydrophilic.
Describe ketones.
Same as aldehydes but not terminal, so less reactive, polar, hydrophilic. Result from protein metabolism.
Describe alcohols.
Involved in fermentation & metabolism, contains a hydroxyl group. Makes polar, hydrophilic, can form hydrogen bonds, soluble.
Describe carboxylic acids.
Found in fatty acids, amino acids. Contains a carboxyl group (combo of carbonyl, hydroxyl). Weak acids, highly reactive, polar, hydrophilic.
Describe aminos.
Found in amino acids, vitamins, neurotransmitters. Contain -NH2 attachment. Reactive, polar, hydrophilic.
Describe the amino acid structure.
Building blocks of proteins, needed to build muscle, make hormones. Humans need 21 amino acids, 9 must be obtained from diet. Contains amino, carboxyl, R-group.
Describe the 5 types of proteins.
Structural = provide structural support ex. collagen, keratin.
Regulatory = hormones, neurotransmitters ex. insulin, substance P
Contractile = MSK ex. actin, myosin
Immunological = protects body from pathogens, ex. antibodies, cytokines
Transport = carry substances ex. albumin, hemoglobin
Catalytic = work as enzymes ex. amylase
Describe the 4 different levels of protein structural organization.
Primary = chain of peptides
Secondary = A-helix, B-sheet
Tertiary = mix of 2/3
Quaternary = mix of tertiary, multiple subunits
Describe carbohydrates.
Organic molecules containing CHO, primary macronutrient. Examples = sucrose, starch, glycogen.
Differentiate between monosaccharides, disaccharides, polysaccharides.
Mono = simplest form of carbs, either pentose (ex. deoxyribose, ribose) or hexose (ex. gluc, fruc, galac)
Di = 2 monos together by dehydration synthesis by glycosidic bond
Poly = long chain of monos, usually insoluble. Ex. glycogen, starches, cellulose
What are the two carbohydrate-induced infant digestive disorders?
Lactose intolerance (lack of lactase), fructosemia (unable to break down fructose, + fructose in blood)
What are some functions and physical properties of lipids?
Functions = protect organs, cell membranes, chemical messengers, store energy in fat cells.
Properties: hydrophobic, non-polar, insoluble
Describe fatty acids.
HC chains with terminal carboxyl (COOH) attachment.
What is the difference between unsaturated and saturated fatty acids?
Saturated = max # of hydrogen attachments
Unsaturated = one or more double bonds. Mono = one, poly = multiple
What is the difference between omega and alpha ends?
Alpha end on a fatty acid = carboxyl attachment.
Omega end = no carboxyl
What are sphingolipids?
Type of lipid found in cell membranes, specifically nerve cells, brain tissue. Have an alcohol and amine attachment.
What are sphingomyelins?
Type of sphingomyelins are found in nerve cell membranes, consist of 25% of lipids in myelin sheaths.
What are eicosanoids?
Fatty acids that signal cell and tissue functions. Derived from unsaturated precursor fatty acid, arachidonic acid.
What are glycerides?
Lipids that contain fatty acids and glycerol. They react with glyceol to form ester bonds.
What are triglycerides?
Most common lipid in body, provide protection, insulation, energy.
What are phospholipids and their three functions?
2 fatty acids and a glycerol/phosphate head. Form membrane structures, act as surfactant, energy transfer in mitocondria
Describe the structure of steroids.
3 cyclohexanes and 1 cyclopentane fused together. Lipophilic, so require a transport protein.
Give examples of steroids. What is the importance of cholesterol?
Sex hormones, mineracorticoids, glucocorticoids. All steroids are derived from cholesterol.
The bicarbonate buffer system occurs _____ in RBC’s and ____ in plasma. Which enzyme speeds up the reaction in RBC’s
Quickly, slowly. Carbonic anhydrase.
Hyperventilation is a sign of ___ pH, hypoventilation is a sign of ___ pH.
High, low
What two acid/base functions occur within the kidneys?
- excretion of fixed acids/H+
- reabsorption of bicarbonate
What occurs in the proximal convoluted tube?
Bicarbonate can return to the blood via a transporter in the membrane of cells. H+ can leave the apical membrane through an Na/K+ pump. Sodium wants to escape.
Name the characteristics of respiratory acidosis (excluding pH).
CO2 = high
HCO3 = normal
Compensation = renal has high H+ excretion, HCO3 reabsorption
Name the characteristics of metabolic acidosis (excluding pH).
CO2 = normal
HCO3 = low
Compensation = hyperventilate
Name the characteristics of respiratory alkalosis (excluding pH).
CO2 = low
HCO3 = normal
Compensation = renal decreased H+ excretion, decreased HCO3 reabsorption
Name the characteristics of metabolic alkalosis (excluding pH).
CO2 = normal
HCO3 = high
Compensation = hypoventilate
Which types of bonds are present in each structure of proteins?
Secondary= H bonds
Tertiary = H, disulphide, ionic bonds
Quaternary = all
Why should aspirin be avoided during pregnancy?
Aspirin decreases synthesis and production of prostaglandins and thromboxane.
What are the three eicosanoids and their functions?
Leukotriene = inflammation/infection
Prostaglandins = contraction
Thromboxane = vasodilation
What are the two main groups of hormones?
Sex/pregnancy, metabolic
Aromatase is an enzyme that catalyzes the final reaction to produce ______. Where is it located, and in which types of cells?
Etradiol. Located in ER of ex. ovarian granulosa cells, testicles, placenta, etc.
Name the acronym “APGAR.”
Appearance, pulse, response to catheter in nostril (grimace), activity, respiration
Nucleic acids are large organic molecules are carry _____ info. Name two examples.
Genetic. DNA, RNA.
Name the three parts of a nucelotide.
Pentose sugar, nitrogenous base, phosphate group.
Name both pyrimidines and purines/their matching. What is different in RNA?
Adenine, thymine = purines, 2 H bonds.
Cytosine, guanine = pyrimidines, 3 H bonds.
Uracil replaces thymine in RNA.
What is the function of RNA? Name some types.
Function is to transmit genetic code for protein creation from the nucleus to ribosomes. Ex. mRNA, transfer, ribosomal.
What are the three steps of DNA replication?
Transcription, translation, polypeptides.
What are mutagens? Name 3 examples.
Anything that cant damage DNA. Oxidizing agents, alkylating agent, UV rays.
What are the three types of mutations of DNA?
point mutations, deletions, chromosomal translations.
Name the function of the nucleus.
Large organelle that contains DNA, main functions are cellular division and control of genetic info.
Name of the functions of the cytoplasm.
Contains organelles between plasma membrane and nucleus.
What do ion channels do? Transporter/carrier proteins?
Ion channels allow specific ions to move through pores.
T/C proteins selectively move substances through membrane.
What are the three forms of transport across the cell membrane? Describe.
Passive = concentration gradient through diffusion.
Hydrostatic pressure = mech. force of water pushing against membranes.
Active = cellular energy used to drive substance against gradient
What do proteasomes do?
Large protease structures within cytosol to remove faulty proteins.
What are the functions of lysosomes? Peroxisomes?
Lysosomes: digest organelles/cells, can do outside body.
Peroxisomes: detoxify drugs/alcohol, found in large quantities in the liver.
