Week 12: Questions

Question 1

What are the three types of molecules that are sources of energy for our cells? Describe the basic chemical structure of each type of molecule.

Answer 1

Carbohydrates
Made from simple carbs are made from a single sugar (glucose), complex ones are made of many sugars bonded together
Found in bread, rice, pasta, fruits/veggies, etc.
Release energy gradually

Proteins
Made from amino acids
→ 20 different types altogether and we can synthesize 12 of these on our own, but get the other 8 ‘essential” amino acids from our diets
Found in fish, meat, eggs, grains, nuts, etc.
Regulate chemical reactions in the body

Fats
Lipids composed of fatty acids and glycerol
Found in meat, dairy, nuts, vegetable oils
Insulate the body from heat los, act as “shock absorbers”, serve as building blocks for hormones and other signal molecules

Question 2

Which type of molecule yields the highest amount of energy per gram?

Answer 2

Fats
They yield twice the energy than carbohydrates and proteins do

Question 3

Why are vitamins and minerals referred to as micronutrients?

Answer 3

Because only small amounts are needed in the diet

Question 4

Fiber cannot be fully digested in the human gut. Why is it an important component of a healthy diet?

Answer 4

It ensures that solid wastes are eliminated regularly and efficiently, which lowers the risk of developing cancers of the large intestine

Question 5

What are the basic food groups?

Answer 5

Fruits. Vegetables, proteins, grains and dairy

Question 6

What is the importance of water in our diet?

Answer 6

It maintains normal blood pressure, eliminates solid wastes from the body, maintains body temperature
Helps with the movement of nutrients, oxygen and other materials through the bloodstream and into tissues/cells

Question 7

Where does carbohydrate digestion begin?

Answer 7

In the mouth where saliva breaks carbs down into their simple sugar subunits

Question 8

What is the breakdown product of carbohydrates that is absorbed in the intestine?

Answer 8

Glucose (sugar subunits)

Question 9

How are carbohydrates stored in the body?

Answer 9

They are converted into fat and stored in body fat cells

Question 10

Where does protein digestion begin?

Answer 10

In the stomach where there is a secretion of acid that digests proteins

Question 11

What is the breakdown product of protein that is absorbed in the intestine?

Answer 11

Amino acids (protein subunits)

Question 12

What is the role of the pancreas in digestion?

Answer 12

Secretes enzymes that digest carbohydrates, proteins and fats, and break them down into the smaller building blocks (sugars, amino acids, fatty acids)

Question 13

What is the role of bile in fat digestion?

Answer 13

Helps to dissolve fats and makes it easier for fat dissolving enzymes to do their work

Question 14

What is absorbed in the large intestine (colon)?

Answer 14

Water, salt and some vitamins

Question 15

What is the essential role of each of the steps of cellular respiration?

Answer 15

Glycolysis
Occurs in the cytoplasm of cells
Begins with glucose to produce two molecules of ATP and pyruvic acid

Krebs cycle
Occurs in the mitochondria
Begins with pyruvic acid produces GTP and NADH

Electron transport chain
Occurs in the mitochondria
Takes electrons from NADH which creates an electron flow, activating an enzyme that produces ATP

Question 16

Which of the three steps of cellular respiration produces the majority of the ATP?

Answer 16

The electron transport chain

Question 17

Why is ATP called “the energy currency of the cell”?

Answer 17

Because it it is used in almost all chemical actions that require an input of energy

Question 18

what percentage of British Columbians is considered obese (with a BMI over 30)?

Answer 18

15-19%

Question 19

What are the sources of error using BMI to measure percent body fat?

Answer 19

It does not take into account sex, frame size or muscle mass

Question 20

What are the sources of error using caliper measurement?

Answer 20

Scale Misreading

Question 21

What happens to our health based on calorie intake?

Answer 21

To maintain health, the energy consumed in food calories should balance the energy spent
If a person does not eat enough: they will lose weight
If a person eats more than is needed: they will gain weight (excess calories are stored as fat)

Question 22

What are some eating disorders that are detrimental to health?

Answer 22

Anorexia nervosa
Individuals starve themselves and excessively exercise
The loss of minerals can lead to kidney damage, muscle cramps, irregular heart rhythms and cardiac arrest
The depletion of body fat stops the production of hormones necessary for a menstrual cycle
Can lead to osteoporosis (thinning bones)

Bulimia nervosa
Individuals consume large amounts of food in a short time (binge) which causes them to then starve or purge (vomit, take laxatives)
Same negative consequences as anorexia
Dental and gum issues because the exposure to acidic vomit
Stomach rupture from repeated vomiting
Fatal dehydration

Binge eating disorder
Individuals binge eat
Exercise disorder
Individuals exercise for several hours a day to change their appearance

Bigorexia
Individuals perceive themselves as “weak” and spend hours a day exercising to to bulk up

Question 23

Effects of steroids

Answer 23

In men: shrinkage of the testicles and reduced sperm count
In women: increased body hair and smaller breasts
Kidney damage, liver damage, heart disease, acne and psychological problems

Question 24

Distinguish between your axial skeleton and your appendicular skeleton.

Answer 24

The axial skeleton is composed of the skull, spine, rib cage and coccyx
The appendicular skeleton is composed of the hips, shoulders and limbs

Question 25

How do ligaments and tendons facilitate movement?

Answer 25

They connect the various parts of our bodies together, which allow for us to have different dimensions of movement

Question 26

Distinguish among skeletal, cardiac, and smooth muscle. Where is each type of muscle found in the body?

Answer 26

Skeletal muscles
Found attached to bones
Contract or shorten to allow bones to move

Cardiac muscles
Found in the heart
Allows the heart to beat

Smooth muscles
Found in layers built into our blood vessels, bladder, intestines and uterus
Produce slower, sustained contractions that move blood, waste, urine and babies along

Question 27

What is the structure of a muscle?

Answer 27

Muscles are made of parallel arrays of filaments
Each of these filaments is made up of muscle fibers
Each of these fibers is actually a single cell
Within each of these cells, there are long myofibrils (also aligned parallel to each other)
Each myofibril is composed of units called sarcomeres

Question 28

Describe the organization of a sarcomere within a muscle myofibril?

Answer 28

The sarcomeres contain thin filaments (made of protein actin) and thick filaments (made of myosin and another protein)
The thin filaments are anchored to z discs (structures that form the end of sarcomeres)

Question 29

What happens in the sarcomeres of your bicep muscles as you contract the muscles to lift weights?

Answer 29

They shorten because muscles contract by shortening individual sarcomeres

Question 30

When a person dies, ATP is no longer produced by cellular respiration. How does this lead to rigor mortis, in which the muscles contract and cannot relax for a few hours following death?

Answer 30

Myosin is physically attached to the actin filament, and ATP is required for them to let go of each other
When a person dies and ATP is no longer produced, myosin and actin are still attached which causes the muscles to contract and be unable to relax

Question 31

How do the training regimens for bodybuilding, weight lifting, and cardiovascular fitness differ? What is the goal of each form of exercise?

Answer 31

Bodybuilding
Work with weights at lower levels than the maximum they can move and focuses on sets of repetition
Work to produce significant growth of muscle size by increasing the volume of a fluid filled structure which surrounds the muscle fibers

Weight lifting
Use sustained, long term strength training with weights that are set at 80-90% of of the maximum weight they can move
This increases muscle strength by causing muscle cells to make more actin and myosin (therefore more muscle fibrils) which will improve strength

Cardiovascular fitness
Jogging, swimming, running, biking, etc.
Strengthens the heart so that it can pump blood more efficiently because during exercise, the heart pumps faster which makes it deliver more oxygen to all muscles (including the heart)

Question 32

What are some supplements that can be used with these exercises?

Answer 32

Diuretics
Alter the balance of fluids and salts in the body
Taken to urinate in larger volumes to decrease weight

Creatine
Helps muscles make more ATP and delays muscle fatigue

Vanadium
Supposed to Increases muscle mass

Stimulants
Reduce fatigue, increase alertness and suppress appetite

Question 33

How can weight and health be balanced?

Answer 33

Physical activity
Regular physical activity prevents/improves diseases, benefits muscle strength, bone health, joint structure/function and improves mental health

Sleep and stress management
Stress increases blood pressure, increases the risk of stroke/heart attack, makes it more difficult to sleep
Sleep is important for memory, alertness, regulation of hormones and appetite