Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

BIOL 235 > Chapter 25 > Flashcards

Chapter 25 Flashcards

1
Q

Metabolism

A

All the chemical reactions that occur in the body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Catabolism

A

Exergonic reactions that produce more energy than they consume releasing the chemical energy stored in organic molecules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Anabolism

A

Chemical reactions that combine simple molecules and monomers to form the bodies complex structural and functional components; endergonic reactions Consuming more energy than they produce

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What happens to the energy released in catabolism?

A

40% is used for cellular functions

The rest is converted to heat which helps maintain normal body temperature

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Oxidation

A

Removal of electrons from an atom or molecule the result being a decrease in the potential energy of the atom or molecule

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Dehydrogenation reactions

A

The loss of hydrogen atoms, which happens in most biological oxidation reactions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Reduction

A

Addition of electrons to a molecule, result in an increase in the potential energy of the molecules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the two enzymes that are commonly used by animal cells to carry hydrogen atoms?

A
  1. Nicotinamide adenine dinucleotide (NAD), Derivative of the B vitamin niacin
  2. Flavin adenine dinucleotide (FAD), Derivative of B2 (riboflavin)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Oxidation-reduction or redox reactions are what?

A

Paired reactions that are coupled such as: When one substance is oxidized (exergonic reaction) another is simultaneously reduced

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Phosphorylation

A

The addition of a phosphate group to a molecule which increases its potential energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the three mechanisms of phosphorylation that organisms use to generate ATP

A
  1. Substrate level phosphorylation
  2. Oxidative phosphorylation
  3. Photophosphorylation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Substrate level phosphorylation

A

Generate ATP by transferring a high energy phosphate group from an intermediate phosphorylated metabolic compound-a substrate-directly to ADP. in human cells this process occurs in the cytosal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Oxidative phosphorylation

A

Removes electrons from organic compounds and passes them through a series of electron acceptors called electron transport chain, to molecules of oxygen. this process occurs in the inner mitochondrial membrane of the cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Photophosphorylation

A

Occurs only in the chlorophyll-containing plant cells or in certain bacteria that contain other light- absorbing pigment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the body’s preferred source for synthesizing ATP

A

Glucose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the different fates of glucose?

A
  1. ATP production - Body cells that require immediate energy glucose is oxidized to produce ATP
  2. Amino acid synthesis - Cells throughout the body can use glucose to form several amino acids which can then be incorporated into proteins
  3. Glycogen synthesis - hepatocytes and muscle fibres can perform glycogenesis in which hundreds of glucose monomers are combine to form the polysaccharide glycogen
  4. Triglyceride synthesis - When glycogen storage areas are filled up hepatocytes can transform the glucose to glycerol and fatty acids that can be used for lipogenesis the synthesis of triglycerides, triglycerides are then deposited in adipose tissue which has virtually unlimited storage capacity
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are the four sets of reactions in cellular respiration?

A
  1. Glycolysis - in which one glucose molecule is oxidized and then two molecules of pyruvic acid are produced the reactions also produce two molecules of ATP in to energy containing NADH + H+
  2. Formation of acetyl Coenzyme A - A transition step that prepares pyruvic acid for entrance into the Krebs cycle also produces energy containing NADH + H+ plus carbon dioxide
  3. Krebs cycle reactions these reactions oxidize acetyl CoA and produce CO2, ATP, NADH + H +, and FADH2
  4. Electron transport chain reactions - these reactions oxidize NADH + H+ and FADH2 and transfer the electrons through a series of electron carriers
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Aerobic

A

With oxygen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Anaerobic

A

Without oxygen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Aerobic respiration

A

Reactions that require oxygen such as the Krebs cycle and electron transport chain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Glycolysis does not require oxygen which makes it what kind of reaction?

A

It can occur under aerobic or anaerobic conditions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Anaerobic glycolysis

A

When glycolysis occurs by itself under anaerobic conditions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Glycolysis

A

Chemical reactions split a six carbon molecule of glucose into two 3 carbon molecules of pyruvic acid, Consumes to ATP molecules it produces for ATP molecules for a net gain of two ATP molecules for each glucose molecule that is oxidized

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is the fate of pyruvic acid?

A
  1. If oxygen is scarce, Then pyruvic acid is reduced via an anaerobic pathways by the addition of two hydrogen atoms to form lactic acid. Lactic acid rapidly diffuses out of the cell and enters the blood the hepatocytes remove lactic acid from the blood and convert it back to pyruvic acid
  2. In aerobic conditions most cells convert pyruvic acid to acetyl coenzyme A, this molecule links glycolysis which occurs in the cytosol with the Krebs cycle which occurs in the matrix of the mitochondria pyruvic acid enters the mitochondrial matrix with the help of a special transporter protein
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

How can red blood cells produce ATP because they lack mitochondria?

A

The only way for red blood cells to produce ATP because their lack of mitochondria is through glycolysis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Coenzyme A

A

Derived from pantothenic acid a B vitamin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Acetyl CoA

A

Formed when the acetyl group attaches to the Coenzyme A After pyruvic acid has undergone decarboxylation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Krebs cycle

A

Known as the citric acid cycle, occurs in the matrix of mitochondria and consists of a series of oxidation reduction reactions and decarboxylation reactions that release CO2.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Electron transport chain

A

A series of electron carriers, integral membrane proteins in the inner mitochondrial membrane, cristae that increases its surface area accommodating thousands of copies of the transport chain in each mitochondrion each carrier in the chain is reduced as it picks up electrons and is oxidized as it gives up electrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Chemiosmosis

A

The mechanism of ATP generation links chemical reactions with the pumping of hydrogen ions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Oxidative phosphorylation

A

Chemiosmosis and the electron transport chain together

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What are the different electron carriers?

A
  1. Flavin mononucleotide (FMN) - Flavoprotein derived from riboflavin (vitamin B2)
  2. Cytochromes - Proteins with an iron containing group capable of existing alternately in a reduced form and then oxidized form
    the cytochromes involved in the electron transport chain includes cytochrome b, cytochrome C1, cytochrome C, cytochrome a, and cytochrome a3
  3. Iron and sulphur centres - contain either two or four iron atoms bound to sulphur atoms that form an electron transfer centre within a protein
  4. Copper atoms - bound to two proteins in the chain also participate in electron transfer
  5. Coenzyme Q - is a non-protein low molecular weight carrier that is mobile in the lipid bilayer of the inner membrane
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Glucose anabolism reactions

A

Glycogen and new glucose molecules from some of the products of protein and lipid breakdown

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Glucose storage: glycogenesis

A

If glucose is not needed immediately for ATP production it combines with other molecules of glucose to form glycogen: the only stored form of carbohydrate in the body

insulin from pancreatic beta cells stimulates hepatocytes and skeletal muscle cells to carry out glycogenesis

The body can store 500 g of glycogen 75% in skeletal muscle fibres and the rest in the liver

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Glucose release: glycogenolysis

A

When ATP is required glycogen stored in hepatocytes is broken down into glucose and released into the blood to be transported to cells where it will be catabolized by the process of cellular respiration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Formation of glucose from proteins and fats: gluconeogenesis

A

 When the glycerol part of triglycerides , lactic acid, and certain amino acids are converted in the liver to glucose it is called gluconeogenesis (when glucose is formed from non-carbohydrate sources)

Glucose is not converted back from glycogen but is newly formed

60% of the amino acids in the body can be used for gluconeogenesis

Stimulated by cortisol and by glucagon from the pancreas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Lipids

A

Nonpolar and therefore very hydrophobic

such as triglycerides

they do not dissolve in water

can combine with proteins produced by the liver and intestine which can create Lipo proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Lipoproteins

A

Spherical particles with an outer shell of proteins, phospholipids, and cholesterol molecules surrounding an inner core of triglycerides and other lipids

Each has a different function but all are essentially transport vehicles

Four major classes of lipoproteins are chylomicrons, Very low density lipoproteins (VLDL’s), low density lipoproteins (LDL’s), and high density Lipo proteins (HDL’s)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Apoproteins (apo)

A

Proteins in the outer shell of Lipo proteins that are designated by the letters a A, B, C, D, and E plus a number

they help solubilized the lipoprotein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Chylomicrons

A

form in mucosal epithelial
ells of the small intestine,
transport dietary (ingested) lipids to adipose tissue for storage.

They contain about 1-2% proteins, 85% triglycerides, 7% phospholipids, and 6-7% cholesterol, plus a small amount of fat soluble vitamins

Enter lacteals of intestinal villi and are carried by lymph intervenous blood and then into the systemic circulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Very low density lipoprotein

A

form in hepatocytes,
contain mainly endogenous (made in the body) lipids.
Contain about 10% proteins, 50% triglycerides, 20% phospholipids,
d 20% cholesterol.
transport triglycerides synthesized in
patocytes to adipocytes for storage. Like chylomicrons, they lose
glycerides as their apo C-2 activates endothelial lipoprotein lipase,
the resulting fatty acids are taken up by adipocytes for storage
by muscle cells for ATP production.
As they deposit some of their
glycerides in adipose cells, VLDLs are converted to LDLs.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Low density lipoproteins (LDL’s)

A

contain 25% proteins, 5%
triglycerides, 20% phospholipids, and 50% cholesterol.
They carry about 75% of the total cholesterol in blood and deliver it to cells throughout the body for use in repair of cell membranes and synthesis of steroid hormones and bile salts.
contain a single apoprotein,
apo B100, which is the docking protein that binds to LDL receptors on The plasma membrane of body cells so that LDL can enter the cell via receptor mediated endocytosis

43
Q

High density lipoproteins (HDL’s)

A

contain 40-45% proteins, 5-10% triglycerides, 30% phospholipids, and 20% cholesterol
move excess cholesterol from body cells and the blood and transport it to the liver for elimination.
prevent accumulation of cholesterol in the blood, a high HDL level is associated with Decreased risk of coronary artery disease.

known as “good” cholesterol.

44
Q

Sources and significance of blood cholesterol

A

Sources of cholesterol in the body are foods, but most are synthesized by hepatocytes

Desirable levels of blood cholesterol are total cholesterol under 200 mg/dL

LDL cholesterol under 130 mg/dL

HDL cholesterol over 40 mg/dL

45
Q

Fate of lipids

A

Oxidized to produce ATP, stored in adipose tissues throughout the body and liver, structural molecules, or to synthesize other essential substances like phospholipids, Lipoproteins, thromboplastin, and myelin sheath

To essential fatty acids that the body cannot synthesize are linoleic acid and Linolenic acid (Which include vegetable oils in leafy vegetables)

46
Q

Triglyceride storage

A

Triglycerides stored in adipose tissue constitute 98% of all body energy reserves

Stored more readily than glycogen

47
Q

Lipolysis

A

Triglycerides that are split into glycerol and fatty acids

catalyzed by the enzyme called lipases

Epinephrin and norepinephrine enhance triglyceride breakdown into fatty acids and glycerol

48
Q

Beta oxidation

A

A series of reactions in the first stage of fatty acid catabolism

49
Q

Acetoacetic acid are condensed by

A

Hepatocytes which take to acetyl-CoA molecules at a time as part of normal fatty acid Catabolism

50
Q

What is some acetoacetic acids converted to?

A

Beta-hydroxybutyric acid and acetone

51
Q

What are the three ketone bodies and what is the process called that makes them?

A

Acetoacetic acid beta-hydroxybutyric acid and acetones

ketogenesis

52
Q

Lipogenesis

A

How liver cells and adipose cells synthesize lipids from glucose or amino acids

Stimulated by insulin

occurs when individuals consume more calories than Is needed to satisfy their ATP needs

53
Q

What are proteins broken down into during digestion?

A

Amino acids

54
Q

What are amino acids used for?

A

Oxidize to produce ATP or used to synthesize new proteins for body growth and repair they are not warehoused for future use or excreted in the urine or feces but instead are converted into glucose or triglycerides

55
Q

What activates the transport of amino acids into the body cells?

A

Insulin like growth factors and insulin

56
Q

What are the main functions of proteins?

A

Enzymes, transportation, antibodies, clotting chemicals, hormones, contractile elements in muscle fibres, structural components of the body

57
Q

Protein catabolism

A

Stimulated by cortisol from the adrenal cortex

Proteins from worn out cells are broken down into amino acids some are converted into other amino acids peptide bonds are reformed and new proteins are synthesized as part of the recycling process

The Hepatocytes convert some amino acids to fatty acids, ketone bodies, or glucose

A small amount of amino acids are oxidized to generate ATP via the kerbs cycle and the electron transport chain

58
Q

Deamination

A

Amino group NH2 is removed from amino acids

Occurs in hepatocytes and produces ammonia

59
Q

Protein Anabolism

A

The formation of peptide bonds between amino acids to produce new proteins and is carried out on the ribosome of almost every cell in the body directed by the cells DNA and RNA

Protein synthesis is stimulated by insulin like growth factors, thyroid hormones, insulin, estrogen and testosterone

60
Q

What are the eight essential amino acids not found in the body?

A

Isoleucine, Lucein, lysine, Methionine, threonine, tryptophan, and valine

61
Q

What are the two essential amino acids that are synthesized in the body?

A

Arginine and histidine

62
Q

Complete protein

A

Contain sufficient amounts of all essential amino acids

beef, fish, poultry, eggs and milk contain complete proteins

63
Q

Incomplete protein

A

Does not contain all essential amino acids

leafy green vegetables, legumes, and grains

64
Q

Nonessential amino acids

A

Can be synthesized by body cells

are formed by transamination the transfer of an amino group from an amino acid to pyruvic acid or to an acid in the Krebs cycle

65
Q

What three molecules play a pivotal role in metabolism?

A

Glucose 6-phosphate, pyruvic acid, and acetyl coenzyme A

66
Q

What are the four possible fates that awake glucose six phosphate?

A
  1. Synthesis of glycogen
  2. Release of glucose into the bloodstream
  3. Synthesis of nucleic acids
  4. Glycolysis
67
Q

Each six carbon molecule of glucose that undergoes glycolysis yields what?

A

Two 3 carbon molecules of pyruvic acid

68
Q

What are the anaerobic and aerobic reactions of pyruvic acid?

A
  1. Production of lactic acid, anaerobic
  2. Production of alanine, anaerobic
  3. Gluconeogenesis, anaerobic
  4. Conversion to acetyl CoA, streams towards ATP producing reactions the Krebs cycle and electron transport chain
  5. Entry into the Krebs cycle
  6. Synthesis of lipids
69
Q

Absorptive state of metabolism

A

Ingested nutrients are entering the bloodstream and glucose is readily available for ATP production

70
Q

Postabsorptive state of metabolism

A

Absorption of nutrients from the G.I. tract is complete and energy needs must be met by fuels already in the body
a typical meal requires about four hours for complete absorption

71
Q

Absorptive state reactions That promote the bodies energy needs or used to synthesize proteins?

A
  1. Catabolism of glucose
  2. Catabolism of amino acids
  3. Protein synthesis
  4. Catabolism of few dietary lipids
72
Q

Absorptive state reactions That promote the use of nutrients stores?

A
  1. Glycogenesis
  2. Lipogenesis
  3. Transport of triglycerides from the liver to Adipose tissue
73
Q

Why is homeostasis of blood glucose concentration especially important for the nervous system and red blood cells?

A
  • The dominant fuel molecule for ATP production in the nervous system is glucose because fatty acids are unable to pass the blood brain barrier
  • Red blood cells derive all of their ATP from glycolysis of glucose because they have no mitochondria so the Krebs cycle and electron transport chain are not available to them
74
Q

What are the reactions of the postabsorptive state that produce glucose?

A
  1. Glycogenolysis in the liver
  2. Glycogenolysis in muscle
  3. Lipolysis
  4. Protein catabolism
  5. Gluconeogenesis
75
Q

What are the reactions in the postabsorptive state that are glucose sparing, allowing there to be more glucose in the blood for the brain and red blood cells?

A
  1. Catabolism of fatty acids
  2. Catabolism of lactic acid
  3. Catabolism of amino acids
  4. Catabolism of ketone bodies
76
Q

Regulation of metabolism during the postabsorptive state

A

Regulated by hormones and sympathetic division of the ANS

Sometimes called Auntie insulin hormones because the counter the fact of insulin during the absorptive state

77
Q

Metabolism during fasting and starvation

A

Glycogen stores are depleted within a few hours of beginning a fast catabolism of storage triglycerides and structural proteins can provide energy for several weeks

the amount of adipose tissue the body contains determines the lifespan possible without food

78
Q

Energy balance

A

The precise matching of energy intake to energy expenditure over time

When the energy content of food balances the energy used by all cells of the body body weight remains constant

79
Q

Calorie

A

The amount of energy in the form of heat required to raise the temperature of 1 g of water 1°

80
Q

Kilocalorie (kcal)

A

Often used to express the energy content of foods a kilo calorie equals 1000 cal that’s when we say that a particular food item contains 500 cal we are actually referring to kilo calories

81
Q

Metabolic rate

A

The overall rate at which metabolic reactions use energy

82
Q

What are the factors that affect the metabolic rate?

A
  1. Hormones
  2. Exercise
  3. Nervous system
  4. Body temperature
  5. Ingestion of food
  6. Age
  7. Other factors- Gender, climate, sleep, and malnutrition
83
Q

Calorigenic effect

A

Thyroid hormones increase BMR by stimulating cellular respiration

84
Q

Food induced thermogenesis

A

Ingestion of food raises the metabolic rate 10 to 20% due to the energy cost of digesting absorbing and stores nutrients

85
Q

Basal state

A

The body in a quiet, resting, and fasting condition

86
Q

Basal metabolic rate (BMR)

A

The measurement obtained under these conditions: Measuring the amount of oxygen used per kilo calorie of food metabolized

87
Q

Total metabolic rate (TMR)

A

The total energy expenditure by the body per unit of time

88
Q

What are the three components that contribute to the TMR?

A
  1. Basal metabolic rate, 60%
  2. Physical activity, 30-35%
  3. Food induced thermogenesis, 5-10%
89
Q

Non-exercise activity thermogenesis (NEAT)

A

The energy cost for maintaining muscle tone, posture while sitting or standing, and involuntary fidgeting movements

90
Q

Satiety

A

Feeling of fulness accompanied by lack of desire to eat

91
Q

Leptin

A

Helps decrease adiposity, total body fat mass

92
Q

Neuropeptide Y

A

released when leptin and insulin levels are low
a neurotransmitter that stimulates food intake

93
Q

Milanocortin

A

Similar to melanocyte stimulating hormone
stimulated for released by leptin
and also acts to inhibit food intake

94
Q

Ghrelin

A

Produced by endocrine cells of the stomach

plays a role in increasing appetite

stimulates the release of neuropeptide Y from the hypothalamic neurons

95
Q

Mechanisms of heat transfer

A
  1. Conduction - heat exchange that occurs between molecules of two materials that are in direct contact with each other, 3% of body heat is lost this way heat can also be gained
  2. Convection - the transfer of heat by the movement of air or water between areas of different temperatures, 15% of body heat is lost to the air
  3. Radiation - the transfer of heat in the form of infrared rays between a warmer object and a cooler one without physical contact, 60% of heat loss
  4. Evaporation the conversion of a liquid to a vapour, 22% of heat loss
96
Q

Insensible water loss

A

Water loss through the skin and mucous membranes of the mouth and respiratory system that we are not aware of

97
Q

Preoptic area

A

A group of neurons located in the anterior part of the hypothalamus is the control centre that functions as the bodies thermostat

receives input from Thermo receptors in the skin and in the hypothalamus and generate action potential‘s at a higher frequency when blood temperature increases and a lower frequency when blood temperature decreases

propagates action potentials to two other parts of the hypothalamus the heat losing centre and the heat promoting centre

98
Q

How do action potentials from the hypothalamus and TSH increase the core temperature to the normal values?

A
  1. Vasoconstriction - decreasing the flow of warm blood and thus the transfer of heat from the internal organs to the skin slowing the rate of heat loss allows the internal body temperature to increase as metabolic reactions continue to produce heat
  2. Release of epinephrine and norepinephrine increasing cellular metabolism which increases heat production
  3. Shivering
  4. Release of thyroid hormones
99
Q

What are the six main types of nutrients?

A

Water, carbohydrates, lipids, proteins, minerals, and vitamins

100
Q

Minerals

A

Inorganic elements that occur naturally in the earths crust

constitute 4% of total body mass

concentrated most heavily in the skeleton

101
Q

Vitamins

A

Vitamins do not provide energy or serve as the bodies building materials most vitamins with known functions are co-enzymes

102
Q

Fat soluble vitamins

A

Vitamin A, D, E, and K are absorbed along with other dietary lipids in the small intestine and package in the chylomicrons

103
Q

Soluble vitamins

A

Several B vitamins and vitamin C are dissolved in body fluids excess of these are excreted in the urine

104
Q

Antioxidant vitamins

A

Three vitamin C, E, and beta carotene

Inactiate oxygen free radicals

Protect against some kinds of cancers, reducing the buildup of atherosclerotic plaque, delaying some effects of ageing, and decreasing the chance of cataract formation in the lens of the eyes

BIOL 235 (28 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions