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FOUNDATION MEDICINE > Biochemistry from Principles Collated Flashcards > Flashcards

Biochemistry from Principles Collated Flashcards

1
Q

Bond strengths in order. Strongest to weakest?

A 
Covalnt 
Ionic 
Hydrogen 
Hydrophobic interactions 
VDW's
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2
Q

Oxidation states of carbon?

A 
Alkane (in fats)
Alcohol (in carbs)
Aldehyde 
Carboxylic acid 
Carbon dioxide
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3
Q

What is the function of micelle

A

helps in the absorption of large lipid molecules, once inside an enterocyte, these lipids are processed and packaged via the rough and smooth endoplasmic reticulum and the Golgi body into a chylomicron for absorption into the lymphatic system.

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4
Q

What forms the outer shell of micelles?

A

Bile salts and a single phospholipid layer

Micelles have an important role in aiding the absorption of large lipid compounds in the small intestine. They are formed from an outer shell of bile salts, which act as a surfactant to emulsify fat droplets, and a single phospholipid layer, which provides the amphiphilic property (i.e., both hydrophilic heads and hydrophobic tails). The core of the micelles contain long-chain free fatty acids, monoglycerides, and cholesterol, as well as fat-soluble vitamins

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5
Q

4 major classes of biomolecules and what they consist of?

A

Proteins/peptides= amino acids
Lipids= triglycerides, phospholipids, steroids
Nucleic acids= DNA/RNA
Carbs= Mono, di, poly saccharides

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6
Q

Example of monosaccharide?

A

Glucose

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7
Q

Examples of disaccharides?

A

Lactose

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8
Q

Examples of polysaccharides?

A

Cellulose

Glycogen

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9
Q

1st law of thermodynamics?

A

Energy can neither be created nor destroyed

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10
Q

2nd law of thermodynamics?

A

When energy is converted from one form to another some of that energy becomes unavailable to do work

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11
Q

What type of reaction is it if the change in free energy is negative?

A

Exergonic (can occur spontaneously)

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12
Q

What type of reaction is it if delta G is positive?

A

Endergonic (cannot occur spontaneously)

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13
Q

Entropy?

A

Loss of useable energy

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14
Q

Primary protein structure?

A

Sequence of amino acids

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15
Q

Secondary protein structure?

A

Formation of backbone

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16
Q

Tertiary protein structure?

A

3D structure

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17
Q

Quaternary protein structure?

A

Relative orientation of one polypeptide to another
polypeptide in a multisubunit protein.
Spatial arrangement of multiple subunits.

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18
Q

What holds proteins together?

A

Disulphide bonds (Peptide bonds form the primary structure of protein molecules. Function of this disulphide bond is to stabilize the secondary and tertiary structure of proteins.)

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19
Q

5 elements of a cell?

A 
SER
RER
Mitochondria
Golgi apparatus 
Ribosomes
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20
Q

Structure of DNA?

A 
Nucleoside = base + sugar 
Nucleotide = nucleoside + phosphate
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21
Q

Examples of purines?

A

Adenine and guanine

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22
Q

What is the collective term for the nitrogenous bases adenine and guanine (A&G) found in DNA and RNA?

A

Purines

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23
Q

Examples of pyramidines?

A

Cytosine
Thymine
Uracil

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24
Q

What is the central dogma?

A

DNA is transcribed to RNA, which is translated into protein

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25
Q

A nucleoside has…

A

5C sugar + organic base

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26
Q

A nucleotide has…

A

5C sugar + organic base + phosphate group(s)

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27
Q

Pol II synthesises only stable RNA. True/False?

A

False
Pol II synthesises all RNA. Pol I and III synthesise only stable RNA

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28
Q

DNA polymerase has 3 important characteristics

A

Can only add to existing nucleic acids
Cannot start synthesis on its own
Requires an RNA primer to start replication

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29
Q

To which “end” of the RNA strand are more nucleotides added during transcription?

A

3’ end

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30
Q

What is the catalyst for DNA replication?

A

DNA polymerase

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31
Q

What is required to commence DNA synthesis and replication?

A

An RNA primer

(DNA polymerase can take over after this)

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32
Q

In which two ways is DNA formed and why?

A

Continously or discontinuously

Continuously - DNA is built up from the 5’ to the 3’ end easily - this is the leading strand
Discontinuously - the other strand is built from 3’ to 5’ as it is orientated the other way around - this is the lagging strand

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33
Q

The lagging stand in DNA formation must utilise which type of fragments to enable 5’ to 3’ directional growth?

A

Okazaki

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34
Q

Which enzyme is reponsible for unwinding DNA?

A

DNA helicase

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35
Q

Which enzyme is reponsible for synthesising an RNA primer to initiate replication on the lagging strand?

A

Primase

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36
Q

Describe how Okazaki fragments aid the growth of the lagging strand

A

Short newly synthesised DNA fragments - Okazaki fragments are added at intervals from the open DNA strands downwards
This allows nucleotides to be sythesised in the “correct” direction by essentially filling in the gaps the Okazaki fragments created
Each time DNA helicase opens up the strand a little more, a new Okazaki fragment can jump in and allow synthesis back down the chain

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37
Q

Which enzyme is key in proofreading?

A

DNA polymerase

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38
Q

What are the three differences between DNA and RNA?

A

Single vs double stranded
DNA - thymine, RNA - uracil
RNA - ribose sugar, DNA - deoxyribose sugar

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39
Q

Which enzymes are responsible for RNA production?

A

RNA polymerases

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40
Q

Which variation of RNA polymerase will synthesise mRNA?

A

Pol II

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41
Q

Where will RNA polymerase bind on a section of DNA?

A

Sections of DNA called promotors

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42
Q

What is characteristic about promotor regions on DNA?

A

They all have the TATA box sequence which marks the beginning of the relevant gene

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43
Q

What are enhancers?

A

Short regions of DNA that can be bound by protein activators to increase the liklihood of transcription

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44
Q

How can enhancers have an influence if they are far from the promotor sequences?

A

Looping of the strand allows them to come into contact
Which is why mRNA form a stem loops.

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45
Q

Q
Enzymes can affect the equilibrium position of a reaction. True/False?

A

False
but it reduce the time to reach equilibrium

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46
Q

How do enzymes lower the activation energy of a reaction?

A

Bind to and stablise the transition state and provide alternative reaction pathways

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47
Q

How do enzymes lower the activation energy of a reaction?

A

Bind to and stablise the transition state and provide alternative reaction pathways

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48
Q

Enzyme with a cofactor is called a…

A

Holoenzyme

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49
Q

Induced fit model describes enzyme-substrate interaction by…

A

Binding of substrate induces a conformational change in the enzyme, resulting in complementary fit

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50
Q

Trypsin and chymotrypsin work in the ____ and have an optimum pH of _

A

Small intestine, 7

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51
Q

What are isozymes?

A

Catalyse same reactions as enzymes but have different properties and structure

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52
Q

CK is an isozyme. The M form is produced in ____ and the B form is produced in the ___. MB form is produced in the ___

A

Skeletal muscle, brain, heart

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53
Q

Which enzymes carry out phosphorylation?

A

Kinases

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54
Q

What are zymogens?

A

Inactive precursors of an enzyme

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55
Q

Where are trypsinogen and chymotrypsinogen formed? Why is it important they are produced inactive?

A

Pancreas
They would digest the pancreas if active

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56
Q

Which enzyme activates trypsinogen? Where does this occur?

A

Enteropeptidase
Small intestine

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57
Q

How many nucleotides do anticodons consist of?

A

3 E P and A

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58
Q

What is TFIID?

A

General transcription factor required for Pol ii transcribed genes

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59
Q

What do anticodons from tRNA form with codons of mRNA?
How many possible combinations?

A

Base pairs
64

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60
Q

Number of possible amino acid types?

A

v

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61
Q

What is the start codon in translation?

A

AUG

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62
Q

Stages of Translation?

A

Initiation
Elongation
Termination

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63
Q

What happens in initiation of translation?

A

-GTP provides energy
-Ribosomal sub-unit binds to 5’ end of mRNA and moves along until it finds start codon
-Initiator tRNA pairs to start codon
-Large sub-unit joins assembly and initiator tRNA is locked in P site

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64
Q

What happens in elongation stage of translation?

A

-Elongation factor brings aminoacyl - tRNA to A site
-GTP
-Second elongation factor regenerates the 1st to pick up next aminoacyl tRNA
-Peptidyl transferase catalyses peptide bond formation between the amino acids in P and A sit

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65
Q

What happens in termination stage of translation?

A

-Occurs when A site of ribosome encounters a stop codon (UAA, UAG, UGA)
-Finished protein cleaves off tRNA

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66
Q

How many tRNA binding sites and their names?

A

3 sites
E, Aminoacyl (A), Peptidyl (P)

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67
Q

What do the terms “degenerate” and “unambiguous” mean in the context of the genetic code?

A

Degenerate: More than one codon can code for the same amino acid.

Unambiguous: Each codon codes for only one amino acid.

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68
Q

Induced fit model describes enzyme-substrate interaction by…

A

Binding of substrate induces a conformational change in the enzyme, resulting in complementary fit

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69
Q

Vmax is?

A

The maximal rate of reaction at unlimited substrate concn

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70
Q

Km is?

A

The concn of substrate which gives 50% maximal rate, i.e. 0.5Vmax

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71
Q

A low Km means…

A

An enzyme only needs a little substrate to work at 0.5Vmax (it has high affinity)

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72
Q

Vmax can be obtained from a Lineweaver-Burk plot by looking at the interesection with the X axis. True/False?

A

False
Intersection with X axis is Km; intersection with Y axis is Vmax

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73
Q

In non-competitive inhibition, Vmax is ___ and Km is ___

A

Decreased, stays the same

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74
Q

enzymes are stabilised intermediate that are formed as substitutes are converted to products True /false

A

True

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75
Q

enzymes catalyse the transition state to avoid the loss of free energy True/False

A

True

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76
Q

prosthetic group

A

its tightly bound coenzymes

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77
Q

Which amino acid is neither D nor L in configuration.

A

glycine

78
Q

Which complex does not pump protons as electrons pass through the respiratory chain?

A

complex II

79
Q

How many ADP molecules (per glucose) are phosphorylated to ATP via substrate phosphorylation reactions during glycolysis?

A

2

80
Q

How many NAD+ molecules are reduced in the degradation of palmitoyl-CoA to form eight molecules of acetyle-CoA?

A

7

81
Q

The enzyme glucose-6-phosphatase is only found in cells which have this function or ability:

A

ability to store glycogen
only in the liver

82
Q

what is the carrier molecule for transporting fatty acids through the inner mitochondrial membrane?

A

The carrier molecule for transporting fatty acids through the inner mitochondrial membrane is “carnitine”.

83
Q

which mechanisms is used for ATP synthesis in the glycolytic pathway?

A

substrate phosphorylation.

84
Q

malignant cancer develops in the glands that line your organs. Common forms of adenocarcinoma include breast, stomach, prostate, lung, pancreatic and colorectal cancers.

A

An adenocarcinoma

85
Q

What happens when a stop codon is reached by a ribosome (in the A site).

A

A termination protein binds to the codon, and blocks access to the ribosome’s A site. Aminoacyl-tRNA synthesase cleaves the protein from the ribosome

86
Q

allosteric?

A

Allow effectors to bind to the protein, often resulting in a conformational change and/or a change in protein dynamics.

Bind to site other than the active site.

Effectors that enhance the protein’s activity are referred to as allosteric activators, whereas those that decrease the protein’s activity are called allosteric inhibitors.

87
Q

proteins which catalyse phosphorylation reactions?

A

Kinases

88
Q

Enzymes are able to……

A

increase the velocity of a reaction by decreasing the energy
of activation

89
Q

There are hydrogen bonds parallel to the helix axis true / false

A

True

90
Q

buffering capacity?

A

The extent to which a buffer solution can counteract the effect of added acid or base

91
Q

which will stay the same in catalyse reaction compare to uncatalyzed reaction

A

that the activation energy required for the reaction to proceed will be lowered in the catalyzed reaction, resulting in a faster rate of reaction, but the free energy and entropy changes will be the same as in the uncatalyzed reaction.

92
Q

Delta G and what is it depend on ?

A

is the difference in free energy between the products and the reactants. If this value is negative, the reaction is spontaneous, if it is positive, the reaction is non-spontaneous, and if it is zero, the reaction is at equilibrium.

ΔG depends on the concentration of both reactants and products because the concentration of reactants is the determinant of reaction quotient (Q) that forms free energy. Therefore a change in the concentration of products and reactants will cause a corresponding change in Q, which directly affects ΔG .

At low temperatures, ΔG will be negative because of the effect of the negative ΔH, but as you increase the temperature, the effect of the positive -TΔS will eventually outweigh that. The value of ΔG will then become positive, and the reaction will no longer be feasible.

ENZYME CONCENTRATION ALSO EFFECT ΔG

93
Q

Types of bonds formed in
Primary
Secondary
Tertiary
Quaternary structure

A

-Covalent bond as peptide bonds formed during condensation reaction.
- Hydrogen bonds btween alpha helices and Beta-pleated sheets along the backbone of the chain.
- Salt bridges , Hydrogen bond , disulfide bonds and hydrophobic/philic interactions.
-made of two or more individual polypeptides. similar bonds of tertiary structure

94
Q

glands vs Glandular epithelium,

A

Gland is an organ

Glandular epithelium its a epithelium tissue

95
Q

Which bond is associated with the linear structure of glycogen?

A

α-1,4-glycosidic bond is associated with the linear structure of glycogen. Glycogenin, a protein primer enzyme, and glycogen synthase are able to add UDP-glucose to the polysaccharide chain via the α-1,4-glycosidic bond. During this process, UDP is cleaved off

96
Q

What is glycogenesis?

A

Synthesis of glycogen from glucose

97
Q

What is glycogenolysis?
A

A

Breakdown of glycogen to form glucose

98
Q

Glycogenolysis occurs by hydrolysis. True/False?
A

A

False
Occurs by phosphorolysis
(using phosphate instead of water )

99
Q

Where is glycogen stored in the body?
A

A

Liver
Muscle cells

100
Q

What is the role of skeletal muscle glycogen?
A

A

Not used to maintain blood glucose; provides energy via glycolysis and TCA cycle during physical activity

101
Q

Which bonds link glucose molecules to form glycogen?
A

A

Alpha-1,4-glycosidic bonds

102
Q

Which bonds create branches in the glycogen chain?
A

A

Alpha-1,6-glycosidic bonds

103
Q

Glycogen formation can be started by two glucose monomers joining together. True/False?
A

A

False
Glucose residues can only be added to an existing glycogen chain known as Glycogenin (primer of at least 4 glucose residues)

104
Q

Glycogen act as long term storage TRUE?FLASE

A

FLASE
Glycogen functions as a form of energy storage for rapid, short-term access compared with triglyceride storage in adipose tissues (i.e., fat), which are for long-term storage.

105
Q

Glycogenesis occurs in six steps

A
  1. Activation stage
  2. Formation of UDP-glucose
  3. Anchoring of UDP-glucose
  4. Polymerisation stage
106
Q

Which enzyme effectively adds glucose monomers to Glycogenin to produce glycogen?
A

A

Glycogen synthase (transacetylase)

107
Q

When enough glucose is present, glycogen synthesis begins: glucose-6-phosphate is converted to what?
A

A

Glucose-1-phosphate
This is know as isomerisation reaction

108
Q

What is formed from glucose-1-phosphate in glycogen synthesis?
A

A

UDP-glucose

109
Q

What is UDP-glucose?
A

A

Essentially an active form of glucose

110
Q

Transacetylase function during glycogen synthesis

A

it introduces ⍺ 1-6 glyosidic links (new branches) approx. every 10 glucose residues

111
Q

Glycogen synthase adds only one glucose at a time to UDP-glucose to ultimately form glycogen. True/False?
A

A

True

112
Q

How often are branches introduced into the glycogen chain?
A

A

Every 10 glucose molecules

113
Q

When does glycogenolysis occur?
A

A

Between meals to maintain blood glucose levels

114
Q

Glycogen phosphorylase cleaves off only one glucose at a time from glycogen. True/False?
A

A

True

115
Q

What are the 2 regulatory actions of insulin upon glycogen synthesis?
A

A

Stimulates glycogen synthesis
Inhibits glycogen phosphorylase

116
Q

What are the 2 regulatory actions of glucagon upon glycogenolysis?
A

A

Stimulates glycogen breakdown
Inhibits glycogen synthase

117
Q

What is gluconeogenesis? When does it occur?
A

A

Gluconeogenesis is a metabolic process in the liver and kidneys that produces glucose from non-carbohydrate sources. It occurs during fasting, exercise, and in certain disease states Occurs when glycogen stores are completely depleted

118
Q

Where does gluconeogenesis mainly occur?
A

A

Liver

119
Q

Name the 3 main precursors for gluconeogenesis
A

A

Lactate (lactic acid)
Amino acids
Glycerol

120
Q

Which TCA cycle intermediate is needed for gluconeogenesis? Why is it needed?
A

A

Oxaloacetate (4C)
Accepts acetyl groups from fat breakdown
During gluconeogenesis, oxaloacetate is converted to phosphoenolpyruvate (PEP), which is then used in the production of glucose.

121
Q

Describe the Cori Cycle also called lactic acid cycle,
A

A

Blood transports lactate to liver
Liver converts lactate to glucose
Glucose is released into blood

122
Q

Which type of amino acids can be used to synthesise new glucose?
A

A

Glucogenic amino acids

123
Q

Which type of amino acids cannot be used to synthesise new glucose?
A

A

Ketogenic amino acids

124
Q

What effect do insulin and glucagon have on gluconeogenesis?
A

A

Insulin inhibits gluconeogenesis
Glucagon stimulates gluconeogenesis

125
Q

How does the cellular energy state affect the regulation of gluconeogenesis?

A

Low levels of ATP and high levels of AMP and ADP activate gluconeogenesis to produce glucose as a source of energy. High levels of ATP inhibit gluconeogenesis to conserve energy.

126
Q

what are the ‘non-reversible’ enzymes that are key to gluconeogenesis?

A

Pyruvate carboxylase Pyruvate → oxaloacetate Mitochondria Activator: acetyl-CoA Inhibitor: ADP
PEP carboyxlase Oxaloacetate → phosphoenolpyruvate Cytosol

Fructose-1,6-biphosphatase Fructose-1,6-biphosphate → fructose-6-phosphate Cytosol

Glucose-6-phosphatase Glucose-6-phosphate → glucose Endoplasmic reticulum Deficient in von Gierke’s disease
Not present in muscle (why muscles cannot generate glucose)

127
Q

What happens when increased fat intake is not coupled with appropriate energy expenditure?
A

A

OBESITY
Increase in number and size of adipocytes

128
Q

Fat provides us with 2x more energy than carbohydrates. True/False?
A

A

True

129
Q

Name some fat-soluble vitamins
A

A

Vitamin A, D, E, K

130
Q

What do triglycerides consist of?
A

A

Glycerol attached via ester bond to 3 fatty acids

131
Q

Double bonds in fatty acids are usually in the trans configuration. True/False?
A

A

False
Usually in cis configuration

132
Q

What effect do double bonds have on the melting point of fatty acids?
A

A

The greater the no. of double bonds, the lower the melting point

133
Q

What are the main products of lipid digestion?
A

A

Glycerol
Fatty acids
Monoglycerides

134
Q

What must happen to long-chain fatty acids to make them transportable?
A

A

Resynthesised to triglyceride and coated into a chylomicron, which enters the lymph

135
Q

What happens to chylomicrons at muscle and adipose tissue?
A

A

Cleaved by lipoprotein lipase into free fatty acids

136
Q

What happens to free fatty acids at muscle and adipose tissue?
A

A

Resynthesised into triglyceride or oxidised to provide energy
depend on the amount of energy needed

137
Q

Where does further oxidation of fatty acid occur?
Why is this a problem for acyl-CoA?
A

A

Oxidation occurs in the mitochondrial matrix
acyl-CoA is formed in the cytoplasm!

138
Q

What transports acyl-CoA into the mitochondrial matrix?
A

A

Carnitine shuttle

139
Q

How is acyl-carnitine formed in the cytoplasm?
A

A

Fatty acids are transferred from acyl-CoA to carnitine to form acyl-carnitine

140
Q

How does acyl-carnitine get across the inner membrane into the matrix? What happens to the carnitine?
A

A

Via a transporter
Carnitine is cleaved off back into the cytoplasm, leaving acyl group

141
Q

In the matrix, what happens to the free acyl- group?
A

A

Combines with CoA again to form acyl-CoA
Net effect: acyl-CoA ends up in the matrix!

142
Q

What happens to acyl-CoA in the matrix?
A

A

Shortened by 2C to form acetyl-CoA and a new acyl-CoA

143
Q

What are the products of one round of B-oxidation of fatty acid?
A

A

1 acetyl-CoA
1 acyl-CoA, shortened by 2C
1 FADH2
1 NADH + H

144
Q

How and where are ketone bodies formed?
A

A

Formed from acetyl-CoA during B-oxidation in liver mitochondria

145
Q

What is lipogenesis?
A

A

Synthesis of fatty acids

146
Q

Lipogenesis is a reductive process (electrons are required). True/False?
A

A

True

147
Q

What transports acetyl-CoA from mitochondrial matrix into cytoplasm?
A

A

Citrate

148
Q

What is the vital first step in lipogenesis from acetyl-CoA?
A

A

Activation of acetyl-CoA by acetyl-CoA carboxylase into malonyl-CoA

149
Q

Which enzyme catalyses synthesis of long chain fatty acid from malonyl-CoA, acetyl-CoA and NADH?
A

A

Fatty acid synthase

150
Q

Which component of fatty acid synthase carries the growing fatty acid chain during synthesis?
A

A

Acyl-carrier protein (ACP)

151
Q

Synthesis of fatty acids is maximal when carbohydrate is scarce. True/False?
A

A

False
Synthesis occurs when carbohydrate is in plentiful supply + fatty acids are scarce (otherwise lipolysis would occur)

152
Q

Amino acids which are not used for proteins are stored in the liver. True/False?
A

A

False
Amino acids cannot be stored and are degraded if not used as building blocks

153
Q

Where is the major site of amino acid degradation?
A

A

Liver

154
Q

What does amino acid degradation primarily produce?
A

A

Ammonia (NH3) and ammonium ions

155
Q

What are the 3 steps by which urea is formed?
A

A

Transaminiation
De-amination
Urea cycle

156
Q

Which organ is albumin secreted from?
A
Name the main liver-derived plasma proteins (4), in order of increasing molecular weight
A

A

Albumin
alpha-globulins
beta-globulins
gamma-globulins

157
Q

What characteristic of plasma proteins enables them to maintain osmotic pressure which increases fluid movement out of the tissues into the blood?
A

A

They are insoluble - they do not diffuse into the interstitial fluid and only circulate in the blood

158
Q

What proteoglycans composed of?

A

are made up of glycosaminoglycans (GAGs) attached to a hyaluronic acid backbone.

159
Q

Why do amino acids exist as zwitterions?

A

Due to their amino group and their carboxyl group, amino acids exist as zwitterions: there is no overall charge on the molecule, but the separate parts are positively and negatively charged. Which aspect of amino acid structure differentiates different amino acids? All amino acids have the same basic structure, and differ only in their R-groups (the side-chain).

160
Q

How does the structure of fibrinogen help it participate in blood clotting?

A

Its globular regions allow fibrin to generate a network of fibres, whereas its fibrous regions enable extended insoluble clot formation, blocking the wound.

161
Q

What are 3 examples of mixed fibrous-globular proteins?

A

Fibrinogen, actin, myosin

162
Q

What is the function of globular proteins?

A

Their functions are in biological, rather than the purely structural roles of fibrous proteins: they can act as enzymes (e.g. trypsin and lysozyme), transporters (e.g. haemoglobin and transferrin), in protection (e.g. immunoglobulins) and as hormones (e.g. insulin).

163
Q

What forms the secondary structure of the haemoglobin molecule?

A

is mostly alpha helical.

164
Q

Which amino acid is found at every third residue in collagen?

A

Glycine
`is found at every third residue in collagen; this is necessary for the proper folding of collagen

165
Q

Which protein chains bind to form fibrinogen?

A

Fibrinogen is a hexamer, made up of two alpha, two beta and two gamma chains. These chains are bonded together by disulfide bonds

166
Q

What are examples of fibrous proteins?

A

Examples include alpha-keratin, collagen, elastin and proteoglycans.

167
Q

Retention/excretion of CO2 is controlled by ——

A

the lungs – concentration can be changed rapidly

168
Q

H2CO3 is excreted/reabsorbed by ———-

A

kidneys – changes in concentration tend to be slower than CO2

169
Q

what is Acidaemia ?and which two ways it can be cause ?

A

High H+ (low blood pH) Leads to acidosis
cause by Decrease in the HCO3 will shift the equilibrium to the right causing increase HCO3 and H+ production decreasing the blood pH
- also can be caused by increase Co2 will shift equilibrium to the right.

170
Q

Alkalaemia

A
  • Low H+ (high blood pH) which Leads to alkalosis
  • cause by Increase in the HCO3 production will shift the equilibrium to the left casing decrease in H+ production increasing the pH of the blood.
    Decrease CO2 will shift equilibrium to the left causing alkalosis.
171
Q

What is meant by hypoxia? A

A

Lack of tissue oxygen

172
Q

What is meant by hypoxaemia?

A

Lack of oxygen in the blood

173
Q

In COPD patients, we aim for SaO2 of between __ and __ %

A

88 and 92

174
Q

What are the 4 main buffers of pH in the body?

A

Bicarbonate, Haemoglobin, Ammonium, Phosphate

175
Q

Define acidaemia

A

pH less than 7.5

176
Q

Define acidosis

A

A process by which the blood contains excess acid (H+)

177
Q

Define alkalaemia? A

A

pH greater than 7.45

178
Q

Define alkalosis

A

A process by which the blood contains excess base

179
Q

Respiratory changes are monitored by looking at CO2 concn. True/False? A

A

True

180
Q

Metabolic changes are monitored by looking at [H+]. True/False?

A

False
Look at HCO3 concn

181
Q

Metabolic compensation is rapid. True/False? A

A

False
It is slow

182
Q

Respiratory compensation is rapid. True/False? A

A

True

183
Q

If pH is low, PCO2 is high, HCO3 is normal, this is what? A check the summery table somosis

A

Respiratory acidosis

184
Q

If pH is high, PCO2 is normal, HCO3 is high, this is what? A

A

Metabolic alkalosis

185
Q

If pH is low, PCO2 is normal, HCO3 is low, this is what? A

A

Metabolic acidosis

186
Q

If pH is high, PCO2 is low, HCO3 is normal, this is what?

A

Respiratory alkalosis

187
Q

If pH is normal, PCO2 is high, HCO3 is high, this is what?

A

Compensated respiratory acidosis OR
Compensated metabolic alkalosis

188
Q

If pH is normal, PCO2 is low, HCO3 is low, this is what? A

A

Compensated respiratory alkalosis OR
Compensated metabolic acidosis

189
Q

If pH is low, PCO2 is high, HCO3 is high, this is what? A

A

Decompensated respiratory acidosis
pH went down as PCO2 went up; compensation occurred by HCO3 increasing to bring pH to normal; PCO2 went up further to cause lower pH again.

190
Q

where is lacteal lymph and what its function

A

lymphs’ which present in the small intestine and absorb chylomicrons (balls of fat ) as fat acid can not be absorbed by capillaries and slowly make their way up to thoracic duct and get dump into the venous blood.

FOUNDATION MEDICINE (23 decks)

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