A&P Chapter 25 Nutrition

Question 1

What are the two types of Metabolism?

Answer 1

Catabolism and Anabolism

Question 2

Describe Catabolism

Answer 2

The BREAKING of larger molecules into smaller molecules.

IE. Proteins into Amino Acids
Starch into Glucose Etc.

This process occurs both within the Digestive System AND inside individual cells.

Question 3

Describe Anabolism

Answer 3

The BUILDING of smaller molecules into larger ones.

IE. Glucose into Glycogen
Fatty Acids+Glycerol into Triglycerides

THIS CAN ONLY OCCUR INSIDE CELLS.

Question 4

How many kilocalories does the human body consume per day?

Answer 4

Typically 2-5,000 Kilocalories/day.

Question 5

How many calories are there in a Kilocalorie?

Answer 5

1,000

Question 6

What is the definition of a calorie?

Answer 6

Its a measurement of energy, specifically the amount of heat necessary to increase the temperature of ONE GRAM of water by ONE DEGREE CENTIGRADE.

Question 7

How many kcals does it tale to heat 50kg of water from freezing to boiling?

Answer 7

5,000kcals

Question 8

What are the major Monosaccharides?

Answer 8

Glucose, Fructose and Glactose

Question 9

What are the primary sources of fuel molecules in your diet?

Answer 9

Monosaccharides (mainly glucose) which breakdown from Polysaccharides (mainly starch).

Fatty Acids which breakdown from Triglycerides.

It is also possible to use AMINO ACIDS which breakdown from proteins but doing so releases NH2 which picks up an extra H becoming NH3 (Ammonia) which then becomes NH4 which is Ammonium and is very toxic.

Question 10

Why aren’t Amino Acids good sources of energy?

Answer 10

Because using proteins to get Amino Acids releases NH2 which will pick up an extra Hydrogen atom making NH3 which is Ammonia which will pick up another Hydrogen becoming Ammonium which is highly toxic.

Question 11

What happens if you consume more fuel molecules than you can use?

Answer 11

The excess will be stored in a variety of cells.

Diglycerides and Triglycerides will be created and stored in Adipocytes.

Glycogen will be created from Glucose molecules and stored in the Liver and in Skeletal muscle cells (myocytes)

Question 12

One gram of Fatty Acids will yield how many kcals of energy? What about one gram of Monosaccharides? Amino Acids?

Answer 12

Fatty Acids = 9kcals/gram
Monosaccharides = 4kcal/gram
Amino Acids = 4kcal/gram

Question 13

What does the complete catabolism of any type of fuel molecule result in?

Answer 13

Adenosinetriphosphate ATP

Question 14

What are the different parts of ATP?

Answer 14

Adenosine
Ribose
Triphosphate

Question 15

What breaks off ATP to produce energy? What is left over?

Answer 15

A phosphate group PO4. The result is energy and a molecule of ADP (adenosinediphosphate).

Question 16

What are some of the functions of a cell that requires ATP?

Answer 16

Active transport of molecules across the plasma membrane.

Pumping ions for Polarization (Na+/K+ ATPase Pump)

Moving molecules or organelles within a cell.

Synthesizing proteins.

Contraction of myocytes.

Question 17

What is the most common fuel molecule?

Answer 17

Glucose

Question 18

Describe GLYCOLYSIS

Answer 18

It is the FIRST Stage of glucose catabolism. It can occur inside ALL cells.

Oxygen is NOT required for GLYCOLYSIS.

One molecule of Glucose produces 2 molecules of PYRUVIC ACID and 2 molecules of ATP.

Question 19

What does one molecule of Glucose yield in GLYCOLYSIS?

Answer 19

2 Molecules of PYRUVIC ACID and 2 Molecules of ATP, it does this WITHOUT oxygen which makes it ANEROBIC.

Question 20

What happens to the PYRUVIC Acid after GLYCOLYSIS if oxygen is NOT available?

Answer 20

It becomes LACTIC ACID which diffuses out of the cells as a waste product.

Question 21

What happens to the PYRUVIC Acid after GLYCOLYSIS if oxygen IS available? Where does this occur?

Answer 21

The PYRUVIC acid molecules (X2) are further catabolized in the Tricarboxylic Acid Cycle (Krebs Cycle, Citric Acid Cycle).

This occurs as a MATRIX reaction INSIDE the mitochondria of a cell.

Question 22

Describe the Tricarboxylic Acid Cycle

Answer 22

If OXYGEN is available the Tricarboxylic acid cycle will convert EACH PYRUVIC ACID (from the initial GLYCOLYSIS catabolism) gives off one carbon atom and then combines with 3 molecules of Oxygen to produce 3 molecules of CO2, 3 Molecules of H2O and 18 Molecules of ATP.

Question 23

How many molecules of ATP do you get from ONE molecule of glucose if oxygen is NOT present? How many if it IS present?

Answer 23

2ATP without O2 and 38ATP with O2.

Question 24

What happens to excess glucose in blood?

Answer 24

The excess Glucose molecules are joined together to form Glycogen which gets stored in the Liver and in Myocytes (muscle cells) for use later.

Glucose can also be converted to FATTY ACIDS through a process called Lipogenesis. Binding the Fatty Acid tails to Glycerol forms Diglycerides and Triglycerides which can be stored in ADIPOCYTES (fat cells).

Question 25

Describe LIPOGENESIS

Answer 25

The process by which excess GLUCOSE molecules are converted to Fatty Acids which get bound to Glycerol molecules and are stored as Diglycerides and Triglycerides in Adipocytes.

Question 26

What is GLUCONEOGENESIS?

Answer 26

The creation of GLUCOSE molecules from other molecules, primarily products of fat catabolism and amino acid catabolism.

Question 27

Describe LIPOLYSIS

Answer 27

Lipolysis uses Fatty Acids by breaking them down and feeding 2 Carbon atom pieces into the TRICARBOXYLIC ACID Cycle to make ATP.

Question 28

What are some TOXIC products of Catabolism of various molecules?

Answer 28

Nitrogen containing molecules from the catabolism of Amino Acids form which get converted to Urea and removed in the Urine.

Uric acid is formed from the catabolism of nucleic acids which get removed in the urine.

Bilirubin and other products of HEME catabolism are excreted in bile to the intestines and removed in feces.

Question 29

How does the body replace damaged structural molecules?

Answer 29

By using ANABOLISM to build up molecules that are needed. This HAS TO HAPPEN INSIDE CELLS.

Question 30

What process is used during ANABOLISM? What does it produce?

Answer 30

Dehydration Synthesis is used to build larger molecules out of smaller molecules, this results in the release of H2O.

Question 31

What structural molecules are AMINO ACIDS used to replace? What process is used to build them up?

Answer 31

ANABOLISM using DEHYDRATION SYNTHESIS is used to turn Amino Acids into: Enzymes, Contractile Proteins, Membrane Proteins and Glycoproteins.

Question 32

What structural molecules are MONOSACCHARIDES used to replace? What process is used to build them up?

Answer 32

ANABOLISM using DEHYDRATION SYNTHESIS is used to turn Monosaccharides into Glycoproteins, Receptos and Glycolipids.

Question 33

What structural molecules are FATTY ACIDS+GLYCEROL used to replace? What process is used to build them up?

Answer 33

ANABOLISM using DEHYDRATION SYNTHESIS is used to turn Fatty Acids+Glycerol into Glycolipids and Phospholipids.

Question 34

What structural molecules are NUCLEOTIDES used to replace? What process is used to build them up?

Answer 34

ANABOLISM using DEHYDRATION SYNTHESIS is used to turn Nucleotides into Nucleic Acids (DNA/RNA).

Question 35

What are the ESSENTIAL AMINO ACIDS?

Answer 35

They are Amino Acids that can’t be formed from other Amino Acids. You must get them from your diet. There are 11 Essential Amino Acids.

Question 36

What are the ESSENTIAL FATTY ACIDS?

Answer 36

They are the Fatty Acids that can’t be formed from other Fatty Acids. You must get them from your diet. There are 2 Essential fatty acids.

Question 37

Are there any Essential Monosaccharides? What about Nucleotides?

Answer 37

No, ALL monosaccharides and nucleotides can be formed inside the cells from other monosaccharides and nucleotides.

Question 38

Summarize METABOLISM

Answer 38

1. Fuel molecules, structural molecules and other molecules MUST be obtained through diet.
2. Within cells: fuel molecules are catabolized to produce ATP, molecules can be INTERCONVERTED, large structural molecules are formed and Ions are used for many purposes.
3. Old molecules are broken down and waste products are removed.