Lecture 1

Question 1

Glycolysis Basic Formula

Answer 1

Glucose enters the cell through a glucose transporter,
Hexokinase adds a phosphate group to keep it in the cell- Glucose-6-Phosphate
Eventually forms 2 Pyruvate, 2 net ATP, and hydrogen ion

Question 2

Potential Next Steps After Glycolysis

Answer 2

Lactic Acid Fermentation- Often times in anaerobic organisms or when there is a lack of O2, minimal ATP produced
Oxidative Phosphorylation- Needs O2, produces 34-36 ATP molecules

Question 3

Classification of Diabetes

Answer 3

Type 1- Immune system attacks beta cells leading to absolute immune deficiency
Type 2- Often seen in obese patients, highly genetic, ranges from predominantly insulin resistance to predominantly insulin secretory defects
Mature Onset Diabetes of the Young- Single mutation causes beta cell dysfunction
Gestational Diabetes- During pregnancy, 1/3 leads to Type II diabetes later
Genetic Defects in insulin action: type A insulin resistance

Question 4

Evolution and Obesity

Answer 4

• Food was limited through the hunter gatherer experience
• Human fat more likely for sexual selection and for energy storage, far less likely for warmth
• 12,000 years ago, humans shifted from hunter-gatherer to agriculture
• Obesity only became common 200 years ago
• As societies modernized, rate of obesity increased

Question 5

Humans vs Other Species in Obesity

Answer 5

Humans are the fattest of any species with 10-35 percent of the body made up of fat
Weight gain due to pregnancy was an advantage to a degree- lactation requires 500-1000 kcal per day
Thinness has only recently become the ideal

Question 6

Monosaccharides

Answer 6

Cannot be broken down into simpler sugars
Fructose, Glucose, Galactose
Basic formula of (CH2O)n

Question 7

Galactose

Answer 7

• Found in sugar beets, dairy and other polysaccharides
• Determines the blood type
• Galactosemia- Deadly disease in infants where they cannot process galactose

Question 8

Fructose

Answer 8

Found in fruit
Added to foods because it has the highest sugar index
High Fructose Corn Syrup- Mass produced because it is sweet and cheap- plays a role in the obesity epidemic
Fructose bypasses the phosphofructokinase checkpoint in glycolysis and goes straight to lipid synthesis

Question 9

Oligosaccharides

Answer 9

Long chains or branches made up of monosaccharides
2-10 simple sugar molecules
Disaccharides- two monosaccharides bonded together
3 common disaccharides- Lactose, Sucrose, Maltose

Question 10

Maltose

Answer 10

Made of 2 glucose molecules
Made when amylase breaks down starch, also found in germinating seeds as they break down starch stores
also produced when glucose is caramelized

Question 11

Lactose

Answer 11

Galactose + Glucose
Found in dairy products
Most people in the world are lactase deficient, lactase persistence arose through convergent evolution in multiple regions

Question 12

Sucrose

Answer 12

Table Sugar

Glucose + Fructose

Question 13

Fructose vs Glucose

Answer 13

Fructose metabolism in the liver is twice as fast as glucose metabolism, leading to it synthesis of fats
Fructose does not cause insulin release from the pancreas

Question 14

Taste

Answer 14

Chemical Senses- Gustation and olfaction add up to taste
Chemoreceptors respond to chemicals in aqueous solution
Taste- Molecules dissolved in saliva
Smell- Molecules dissolved in fluid in the nasal membrane

Question 15

5 Basic Taste Sensation

Answer 15

Sweet- Sugar, saccharin, alcohol, and some amino acids
Salt- Metal ions
Bitter- Alkaloids
Sour- Hydrogen Ions
Unami- Elicited by the amino acid glutamate

Question 16

Sodium

Answer 16

Glucose transport requires sodium, described as sodium-glucose co-transport as the mechanism for intestinal glucose absorption