Lipids and Proteins Flashcards

Flashcards to review the key concepts about Lipids and Proteins

What are the major lipid groups, their basic structures, food sources, and functions?

Triglycerides (fats and oils), phospholipids, and sterols. Triglycerides: 3 fatty acids + glycerol (energy storage). Phospholipids: glycerol + 2 fatty acids + phosphate (cell membranes). Sterols: four-ring structure (cell membrane structure, hormones).

How does fatty acid saturation level relate to its structure?

Saturated: Straight structure, single bonds, tight packing, high melting point. Unsaturated: Double bonds, kinks, loose packing, low melting point.

Describe essential fatty acids (EFAs), their food sources, functions, and deficiency effects.

EFAs are polyunsaturated fats the body can't synthesize (linoleic acid - omega-6, alpha-linolenic acid - omega-3). Sources are diet. Crucial for bodily functions; deficiency causes health problems.

What is hydrogenation and why is it used in food products?

Hydrogenation is adding hydrogen to unsaturated oils to make them solid/semi-solid, increasing shelf life. Partial hydrogenation can create unhealthy trans fats.

What are the functions of lipids in the human body?

Energy storage, cell structure, hormone production, insulation, fat-soluble vitamin absorption, and organ protection.

What are the guidelines for fat intake?

Limit total fat to 20-35% of daily calories. Focus on polyunsaturated and monounsaturated fats. Limit saturated fat to less than 10%. Keep trans fat as low as possible.

How do you calculate the percentage of fat in a food product?

Divide calories from fat by total calories, multiply by 100. E.g., (60 calories from fat / 300 total calories) * 100 = 20%.

Name the enzymes involved in lipid digestion and where does this digestion occur?

Lingual, Gastric, Pancreatic and Lipoprotein Lipases. Mouth (lingual), Stomach (gastric), Small Intestine (pancreatic), Bloodstream (lipoprotein).

How are lipids carried in the bloodstream?

Lipids are transported via lipoproteins, which are lipid-protein complexes that allow fats to travel in the water-based blood.

What are the health concerns related to excessive fat intake?

Cardiovascular disease, obesity, and certain cancers. Saturated and trans fats raise LDL (bad) cholesterol, increasing heart disease and stroke risk.

What are the structural components of proteins, and how do they differ from lipids and carbohydrates?

Proteins are composed of amino acids linked by peptide bonds. Carbohydrates are monosaccharides. Lipids are fatty acids and glycerol.

What are the steps involved in protein synthesis?

Transcription (DNA's code copied to mRNA) and translation (mRNA used to assemble amino acids into protein at the ribosome).

Why is nitrogen balance important?

Reflects the balance between protein breakdown and synthesis, indicating protein intake adequacy/impact on muscle growth and overall health. Assesses nutritional status.

How do you calculate the RDA for protein in adults?

Convert weight to kilograms (pounds / 2.2). Multiply kg by 0.8 (or pounds by 0.36) to get daily protein RDA in grams.

Name the enzymes involved in protein digestion, and where does this digestion occur?

Pepsin (stomach), trypsin, chymotrypsin, elastase and peptidases (small intestine).

Name a few functions of protein in the human body.

Structural support, regulating processes, transporting materials, balancing fluids, aiding immunity, and providing energy.

What are the causes of kwashiorkor, marasmus, and phenylketonuria (PKU)?

Kwashiorkor: protein deficiency. Marasmus: deficiency of all macronutrients. PKU: genetic disorder, body can't process phenylalanine.

What are the potential harms of excess protein in the diet?

Increased LDL cholesterol, worsening kidney function in people with kidney disease.

Name a few different types of vegetarianism.

Lacto-vegetarian, ovo-vegetarian, lacto-ovo-vegetarian, vegan, flexitarian, pescatarian.