3.2 FOOD STUDY GUIDE

What are factors that can increase or decrease BMR?

-Age - BMR decreases about 5% per decade after turning 40. This is due to the loss of lean muscle mass thus less energy is required to maintain the body's vital processes. Gender - Men have a BMR 5 to 10% higher than women. This can be attributed to their increased lean muscle mass and less fat in their body. -Muscle mass - More muscle burns more calories and results in a higher BMR. -Hormones - Certain hormones are responsible for increasing or decreasing metabolism. For example a decrease in thyroid hormone may lead to approximately a 15% decrease in metabolism. Similarly, there may be a 5% increase in body's metabolism during a woman's luteal phase of the menstrual cycle. -Caffeine, Tobacco - Research shows that consuming caffeine in different amounts between 5 to 100 mg per day may increase body's metabolism by 7%. Even tobacco can cause upto3-7% increase in body's BMR. -Stress/ emotions - stress may lead to an increased production of stress hormones like epinephrine and norepinephrine. This may also lead to an increased heart rate and respiratory rate and an increased metabolism may be required to fulfill these needs. -Exercise: Various forms of exercise can have different effects on our body. Strength training can increase our body's metabolism chronically. This is because it causes an increase in the lean body mass. Aerobic exercise and cardiovascular exercise do not have a significant role in chronically increasing body's basal metabolic rate. -Calorie restriction - Restricitve diets below 100 calories per day may create a problem with the basal metabolic rate. There can be an acute decrease in basal metabolic rate which can be harmful for the individual.

What are the health risks associated with being underweight?

-Anemia & nutrient deficiencies (CARDIO) -Bone loss & osteoporosis (SKELETAL) -Heart irregularities & blood vessels disease (CARDIO) -Amenorrhea (loss of periods for women) (REPRODUCTIVE) -Vulnerability to infection/disease (IMMUNE) -Delayed wound healing (IMMUNE)

What are the health risks associated with being overweight?

-Cancers (IMMUNE) -Depression (NERVOUS) -Type II Diabetes (ENDOCRINE) -Sleep Apnea (RESPIRATORY?) -Asthma (RESPIRATORY) -Osteoarthritis ("swelling of bones/joints") (SKELETAL) -Heart attack or stroke due to CARDIO -High cholesterol -High blood pressure -Arteriosclerosis ("artery hardening")

What are the functions of the digestive system?

-Takes in food - Breaks down food that can absorbed by the bloodstream - Gets rid of unusable materials in the form of feces

What is ATP?

ATP is adenosine triphosphate, the energy molecule used by our bodies to build up tissues.

How is energy releases by ATP?

ATP releases energy by losing a phosphate group and turning into ADP (adenine diphosphate). The breaking of the bond gives off energy.

Explain what happens in the large intestine to cause diarrhea or constipation. How does the function of the large intestine relate to another key resource?

As the waste enters the large intestine, fluid is absorbed from this waste and causes the waste to become dry and hard and causes constipation. When too much fluid remains the waste it would cause diarrhea.

Why is BMI not always accurate?

BMI doesn't distinguish between muscle mass and body fat. Some person may have more muscle than fat and be healthy, but still considered "obese" according to their BMI.

Why do enzymes only work on their specific substrates?

Because each substrate has a specific site for enzyme attachment. For different enzymes, the active site (where the reactants attach) has a different shape.

Body Mass Index(BMI)

Ratio of weight (kg) to height (m)—used to determine whether a person is at a healthy weight

Each gram of fat you consume provides over twice as many calories as a gram of protein or carbohydrates. What does this tell you about your body's ability to burn off these three fuels? Which would require the most energy to burn?

Since each gram of fat you consume provides over twice as many calories as a gram of fat, this tells us that it requires more energy to burn off fats than it does to burn off protein or carbohydrates. It takes the longest amount of time to burn off fats, then proteins and carbohydrates are the easiest to burn off.

What would happen if there were no enzymes in the human body?

The body would not be able to function because it would not be able to absorb nutrients and turn it into ATP

Why is it important to eat a balanced diet containing essential vitamins?

The lettuce would be broken down in the mouth along with the others where then the food would be transported to the stomach to begin digestion. The bread would be moved to the small intestine to fully digested. The turkey would be moved to the pancreas to digested along with the mayonnaise.

Basal Metabolic Rate(BMR)

The rate at which your body uses energy when you are resting in order to keep vital functions going such as breathing.

How does the release of energy happen?

The release of energy occurs in 3 steps: 1. Glycolysis 2. Kreb's Cycle 3. Electron Transport Together, these steps can make 38 ATP molecules from one glucose molecule (taken in through food) that is in the presence of oxygen (aerobic). If there's no oxygen (anaerobic), the process is 15x less efficient!