Updated Midterm study guide

What is the normal fasting blood glucose range?

70–100 mg/dL

What is hypoglycemia?

Blood glucose <70 mg/dL

What is hyperglycemia?

Blood glucose >100 mg/dL (fasting)

Which hormone lowers blood glucose?

Insulin

Which hormone raises blood glucose?

Glucagon

Where is insulin secreted from?

Pancreas (beta cells)

Where is glucagon secreted from?

Pancreas (alpha cells)

What is the main message of insulin?

“Take glucose into cells for energy or storage”

What is the main message of glucagon?

“Release glucose from liver into blood”

What is the storage form of glucose in liver and muscle?

Glycogen

What is the difference between Type 1 and Type 2 diabetes?

Type 1 = autoimmune, no insulin; Type 2 = insulin resistance

What are typical symptoms of diabetes?

Excess thirst, frequent urination, fatigue, blurred vision

What is gluconeogenesis?

Making glucose from non-carbohydrate sources

Why can an overweight person feel hungry after a few hours even with high fat stores?

Brain primarily uses glucose, not fat

Which organ first receives carbohydrates absorbed from the intestine?

Liver

Where are glycogen stores primarily located?

Muscle and liver

About how long do glycogen stores last during continuous exercise?

A few hours

What happens when glycogen stores are full and glucose is still available?

Excess glucose is converted into fatty acids

Which organ metabolizes alcohol primarily?

Liver

Which enzyme converts ethanol into acetaldehyde?

Alcohol dehydrogenase (ADH)

What byproduct of alcohol metabolism causes hangovers?

Acetaldehyde

What is a standard drink?

14 grams of pure alcohol (12 oz beer, 5 oz wine, 1.5 oz liquor)

What are the main effects of excessive alcohol consumption?

Liver damage, nutrient deficiencies, impaired judgment, addiction

Why can alcohol increase risk of nutrient deficiencies?

It interferes with absorption and metabolism of vitamins and minerals

What is a general property of water-soluble vitamins?

Not stored (except B12), excreted in urine, daily intake required, deficiency shows quickly

Which water-soluble vitamin is a powerful antioxidant and prevents scurvy?

Vitamin C

What are the roles of vitamin C?

Antioxidant, collagen synthesis, immune support

What are deficiency symptoms of vitamin C?

Scurvy: bleeding gums, bruising, poor wound healing

What is the main role of B vitamins?

Coenzymes in metabolism

Which water-soluble vitamin is stored in the liver, unlike most others?

Vitamin B12

Why is toxicity rare in water-soluble vitamins?

Excess is excreted in urine

Why is daily intake of water-soluble vitamins necessary?

The body does not store them (except B12)

What is a general property of lipid-soluble vitamins?

Stored in fat/liver, toxicity possible, absorption requires dietary fat

Which vitamin is essential for vision and epithelial cell maintenance?

Vitamin A

What are deficiency symptoms of vitamin A?

Night blindness, dry scaly skin (keratinization)

Which vitamin helps with calcium absorption and bone health?

Vitamin D

What are deficiency symptoms of vitamin D?

Rickets in children, osteomalacia in adults

Which vitamin acts as an antioxidant protecting cell membranes?

Vitamin E

What is a deficiency symptom of vitamin E?

Hemolytic anemia

Which vitamin is essential for blood clotting?

Vitamin K

What are deficiency symptoms of vitamin K?

Prolonged bleeding, especially in newborns

Which fat-soluble vitamin requires dietary fat for absorption?

All (A, D, E, K)

Which fat-soluble vitamin has toxicity risks if over-supplemented?

A, D, E, K

Where is vitamin A stored?

Liver

Where is vitamin D stored?

Fat and liver (also synthesized in skin)

Which vitamin is semi-essential because gut bacteria can synthesize it?

Vitamin K

Which vitamin is involved in the coagulation cascade and also supports bone health?

Vitamin K