Ims: Sfm Block 1 Lecture 1

Front 1

Describe carbohydrate composition.

Back 1

Carbon plus water

Front 2

Define monosaccharide.

Back 2

One sugar

Front 3

Define disaccharide.

Back 3

Two monosaccharides

Front 4

Define oligosaccharide.

Back 4

3 to 12 monosaccharides.

Front 5

Define polysaccharide.

Back 5

Tens to thousands of monosaccharides

Front 6

To which 'building block' do sugars belong?

Back 6

Carbohydrates

Front 7

What carbohydrate category does glycogen fall under?

Back 7

Polysaccharides

Front 8

To which "building block" do sterols belong?

Back 8

Lipids

Front 9

What are the soluble properties of lipids?

Back 9

Soluble in non-polar solvents

Insoluble in water

Front 10

Describe fatty acids.

Back 10

Straight aliphatic chains with methyl group at omega-end and carboxyl group at alpha-end (C=O).

Front 11

When is a fatty acid saturated?

Back 11

When C-C bonds are all single.

Front 12

When is a fatty acid unsaturated?

Back 12

When contains C=C bonds.

Front 13

What is an acylglycerol?

Back 13

Glycerol with three fatty acids attached through an ester linkage to a glycerol backbone.

Glycerol: OH-CH2-CH(OH)-CH2-OH

Front 14

Under what category of lipid does cholesterol belong?

Back 14

Steroids

Front 15

Describe the structure of an amino acid.

Back 15

A compound that contains an amino group and a carboxylic acid group.

Front 16

Describe the structure of a purine, pyrimidine, and pyridine.

Back 16

Nitrogen-containing ring structure

Front 17

What is a nulcoeside?

Back 17

A nitrogen-containing ring structure plus a sugar, usually ribose or deoxyribose

Front 18

What is a nucleotide?

Back 18

A nucleoside with a phosphate attached to the sugar

Front 19

What is the difference between an essential and a non-essential amino acid?

Back 19

Essential amino acids must be acquire through diet.

Non-essential amino acids can be synthesized as needed.

Front 20

Which amino acids are generally regarded as essential for humans?

Back 20

PVT TIM HALL

Phenylalanine
Valine
Threonine
Tryptophan
Isoleucine
Methionine
Histidine
Arginine (conditionally essential)
Leucine
Lysine

Front 21

What is the difference between undernutrition and overnutrition? Relate these to catabolic and anabolic states.

Back 21

Undernutrition is the intake or absorption of fewer calories than energy spent (CATABOLIC). Overnutrition is the expenditure of energy below calories consumed (ANABOLIC).

Front 22

Under which metabolic state do sick patients lie?

Back 22

Catabolic.

Front 23

What is total energy expenditure composed of?

Back 23

Resting (Basal) Energy Expenditure (60%)--this is the cost of all intrinsic metabolic functions

Thermic effect of food (10%)

Modest physical activity (30%)

Front 24

Roughly how much energy (in a non-obese person) is stored as fat?

Back 24

15-25%; this is higher in women

Front 25

What is fat-free mass? What is it proportionate to? List some examples.

Back 25

Non-fat components of body; resting energy expenditure.

Ex: extracellular and intracellular water, bony skeleton, glycogen, skeletal/visceral protein

Front 26

About how much of the body is comprised of water?

Back 26

60%

Front 27

About how much of the body is comprised of protein?

Back 27

17%

Front 28

About how much of the body is comprised of carbohydrates and minerals?

Back 28

6%

Front 29

List the three main energy stores in the human body in order of their abundance. How much energy does each provide as a unit of its mass?

Back 29

Liver Glycogen: 4 Cal/g
Muscle Glycogen: 4 Cal/g
Usable (Muscle) Proteins: 4 Cal/g
Fat (Stored triglyceride): 9 Cal/g

Front 30

What constitutes the body cell mass?

Back 30

The total mass of all the cellular elements in the body which constitute all the metabolically active tissue of the body:

Intracellular glycogen and protein, Intracellular water

Front 31

During a 24 hour fast, how are energy needs initially met?

Back 31

Consumption of liver glycogen stores by conversion of body protein to glucose via gluconeogenesis

Front 32

What metabolic changes occur during long periods of fasting?

Back 32

Resting energy expenditure decreased by as much as 25 percent; ketogenesis (ketone bodies produced from fatty acids) and muscle proteins (provide AA's for gluconeogenesis) provide energy for remaining functions

Front 33

Describe the metabolic changes after the stress of a critical illness? How do these changes come about?

Back 33

Hypermetabolism: demands of accelerated energy expenditure met by skeletal and visceral proteolysis to provide AA's for gluconeogenesis.

Muscle proteolysis is promoted by circulating stress hormones and inflammatory cytokines.

Front 34

What is the absorptive state?

Back 34

2-4 hour period after ingesting a meal when nutrients are being absorbed and food is being digested

Front 35

What metabolic changes occur during the absorptive state?

Back 35

Circulating levels of glucose, AA's, and triglycerides transiently increase. Islet cells in the pancreas secrete insulin which activates anabolic pathways.

Front 36

Through what methods are metabolic pathways regulated? What is the timeline for such events?

Back 36

-Availability of substrates (direct regulation of enzymes via allosteric effects)

Covalent modification of enzymes (ex: phosphorylation via insulin signaling)

Increased synthesis of enzymes

Allosteric control: seconds to minutes
Covalent modificaiton: minutes to hours
Enzyme synthesis: Hours to days

Front 37

What's the difference between exogenous and endogenous energy? What building block provides both?

Back 37

Exogenous = energy obtained through diet
Endonenous = energy obtained through glycogen

Carbohydrates

Front 38

What is a simple carbohydrate? Give examples.

Back 38

Sugar, Sweet; monosaccharides and disaccharides

Front 39

What are the three types of monosaccharides and what are their respective dietary sources?

Back 39

Glucose: Fruits, sweet corn, corn syrup, honey

Fructose: Fruits, honey, HFCP

Galactose: not found in nature; constituent of lactose (found in dairy)

Front 40

What are the three types of disaccharides? What are their monosaccharide components? Dietary sources?

Back 40

Sucrose = Glucose + Fructose; sugar cane, sugar beets (table sugar), molasses, maple syrup

Lactose = Glucose + galactose (dairy)

Maltose: glucose + glucose; beer, malt liquor

Front 41

What are complex carbohydrates?

Back 41

oligosaccharides and polysaccharides; contain more than 2 sugar units; generally not sweet to taste; AKA starch

Front 42

What is fiber?

Back 42

A polysaccharide that resists digestion; since it is not digested, it doesn't provide energy

Front 43

What's the difference between dietary and functional fiber?

Back 43

Dietary fiber is fiber found naturally in food. Functional fiber is fiber that has been shown to have health benefits.

Front 44

What's the difference between soluble and insoluble fiber? In what foods can they be found?

Back 44

Insoluble fiber doesn't dissolve in water and isn't metabolized in large intestine. Found in bran, whole grains.

Soluble fibers dissolve or swell in water and can be metabolized in large intestine. Found in foods containing pectin (fruits, legumes), gums, oat bran, psyllium

Front 45

What is the glycemic index? What type of foods result in a low/high glycemic index?

Back 45

Measure of glucose response to intake of a carbohydrate (polysaccharides --> monosaccharides (if not glucose already)-->Glucose).

Fats delay stomach emptying, so result in lower GI.
Complex carbs result in higher GI (porride from raw oats)

Front 46

What is the difference between fat and oil? Why do they differ?

Back 46

Fat is solid at room temperatue
Oil is liquid at room temperature

Fat is more saturated (fewer double bonds) and thus has a higher melting point

Front 47

What category of lipids are considered essential?

Back 47

Polyunsaturated; omega-3 and omega-6

Front 48

How are polyunsaturated fats named?

Back 48

Location of first double bond from methyl (omega) end, e.g., omega-3

Front 49

What are triglycerides? How are they absorbed?

Back 49

lipid with glycerol backbone and three fatty acids attached by ester linkages; predominant of dietary fats, stored in adipose tissue

Too large to be directly absorbed, requires esterase, pancreatic lipase.

Front 50

What are trans fats? How are they made? What are their benefits?

Back 50

Unsaturated fats that contain trans isomer fatty acids; produced by hydrogenating vegetable oils; less prone to oxidation (goes rancid more slowly); higher burning temperature (can be used in fryer for longer)

Front 51

What are the dietary sources of cholesterol? What is cholesterol's role in the body?

Back 51

Animal products; not an energy source, simply a substrate for hormone synthesis, and is structural constituent of cell membranes

Front 52

How are lipids transported throughout the body? Describe.

Back 52

lipoproteins:

Low Density lipoprotein cholesterol
High density lipoprotein cholesterol (healthy)

Front 53

What are the effects of fats on HDL/LDL?

Back 53

Sat fats increase LDL
Polyunsat decrease LDL
Monounsat decrease LDL
Moderate/high fat diet will increase HDL
Low fat diest will decrease HDL (as well as LDL)

Front 54

What is high quality protein?

Back 54

AKA Complete, contains all essential aa's; primarily of animal origin, or soybean

Front 55

Kwashiorkor vs Marasmus

Back 55

Kwashiorkor: Energy sources are adequate but protein intake is low. May develop swollen abdomen (ascites--fluid in abdomen--due to increased capillary permeability and reduced plasma proteins, resulting in reduced oncotic pressure and increased osmotic flux).

Marasmus: inadequate calories in excess of lack of protein in diet (general starvation). Likely loss of adipose and muscle tissue. Abdominal swelling may also occur.