- The sum of all the chemical reactions that happen in the body.
- Some reactions building reactions
- Others break reactions
Break complex molecules into simpler ones
- Chemical reactions that combine simple molecules to form more complex ones
- Building reactions
What is a nutrient ?
Chemical substances that the body uses for growth, maintenance, or repair
Name the six main types of nutrients.
- 1. water
- 2. carbohydrates
- 3. proteins
- 4. lipids
- 5. vitamins
- 6. minerals
List some of the roles of water.
- Medium in which most reactions occur
- Some reactions water is the
- -helps maintain body temperature
What are the end-products of the digestion of disaccharides and polysaccharides ?
- starches (poly), sugars (di), fruit
- Break them down into monosaccharide's (most famous is glucose) (fructose, galactose)
What is the body’s preferred source of energy for ATP synthesis ?
glucose is body preferred source of energy for ATP synthesis
Briefly describe the body’s four main uses for glucose.
- 1. ATP production
- 2. glycogen (made of glucose molecules hooked together)
- 3. lipid
- 4. amino acids
By what mechanism does glucose typically enter body cells ? What hormone usually facilitates the process ?
- Facilitated Diffusion (uses a carrier molecule, does not need to use ATP)
- Insulin is the hormone needed to get glucose into the body cells
What is gluconeogenesis ?
- Forming glucose from things that are not carbohydrates
- Can turn amino acids or fats into glucose
- Brain needs a certain amount of glucose to make ATP
Describe three of the body’s main uses for lipids.
- Energy Storage
- Production of ATP
- ---Cell membrane made of phospholipids
Are there any fatty acids that the human body cannot synthesize ?
- Linoleic Acid
- Linolenic Acid
What are the end-products of the breakdown of neutral fats ?
Can the body synthesize lipids from glucose ?
Can the body synthesize lipids from amino acids ?
What are the end-products of the digestion of proteins ?
How does the body use amino acids that are produced by digestion ?
- Synthesize new body proteins for growth
- Deaminate it
- Store it as lipid
Can the body store excess amino acids ? What happens to excess amino acids ?
- Not in the form of amino acids
- Convert it to glucose or convert it to lipid
Distinguish between essential and nonessential amino acids. (20 of them)
- Essential: The ones that are essential to be in your diet
- (have to eat)
- Nonessential: You can make them from other sources (amino acids, lipids)
Describe the area of the brain which is involved in controlling food intake
- Thought to have 2 regions controlling food intake
- 2. foumous center (tell body full)
Identify some substances that signal the brain that fullness is attained.
- Distension of the GI tract
- Blood glucose level
- Hormones: (glucogon), CCK (from stomach), estrogens, leptin (from adipose tissue)
Identify some substances that increase appetite.
- growth hormone
- glucocorticoids (when stressed)
What is a mineral ?
Inorganic elements that occur naturally in the earths crust
Name six important minerals and describe how they are used by the body.
- 1. Calcium: bones, muscle contraction
- 2. Phosphorous: bone tissue
- 3. Iron: RBC hemoglobin
- 4. Iodine: thyroid hormone
- 5. Magnesium: ATP synthesis
- 6. Sodium: controls water balance, buffers, nerve impulse
Organic nutrients required in small amounts to maintain growth and normal metabolism.
Generally speaking, how do most vitamins function ?
Can the body make any vitamins ?
- Technically no.
- Vitamin K in intestine
- Vitamin D can be assembled if building blocks in diet
What are the two main groups of vitamins ?
- Fat soluble (A,D,E,K)
- Water Soluble (B, C)
Which type of vitamins can be stored by cells ?
Fat Soluble Vitamins can be stored in fatty tissue in body (can be toxic)
List six vitamins and describe how they are used by the body.
- 1. Vitamin D: To absorb Calcium and phospherous from GI tract
- 2. Vitamin K: Involved in clotting
- 3. Vitamin A: used to make epithelial cells, visual pigments
- 4. Vitamin C: Collogen formation, in many enzymes
- 5. Vitamin B: Niacin to make NAD (needed to make ATP), Riboflavin to make FAD (carrier takes electrons to electron transport chain)