MICRO Study guide 8 and 9

Chapter 8

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Define catabolic pathway

Breaks down the substances and releases energy

Define anabolic pathway

Combine energy and molecules to build new substances

Define amphibolic pathway

Dual role, can be used for both breaking down and building substances

Define ATP

Adenosine triphosphate. Made by catabolic reactions and provides the
energy for anabolic reactions

Define ADP

Adenosine diphosphate. Contains two phosphate groups

Define AMP

Adenosine monophosphate. Formed when cells dephosphorylate ADP
(remove last phosphate group of ADP)

Define catalyst

Only needed in small amounts to make a reaction happen faster. Not
permanently changed

Define reaction rate

Speed at which a reaction occurs

Define active site

Site of an enzyme that interacts with the substrate to generate a
chemical reaction

Define activation energy

Minimum amount of energy required to start a chemical reaction

Define reactant

Held by cells in their proper orientation and lower the energy
required for starting, using enzymes

Define product

End result

Define coenzyme

Cofactors that can move about to other factors anchored to the enzyme
they help, can be vitamins, can collect electrons from one reaction
and shuttle them to other reactions. In metabolism include NAD+,
NADP+, FMN, and FAD

Define cofactor

Needed by enzymes to function

Define ribozymes

Enzymes that are made of nucleic acid RNA

Define denatured

Enzymes and other proteins. Exposure to high temperatures, lose 3D
structure, and become nonfunction. Can be reversible and irreversible

Define allosteric activation

When a regulatory molecule increases enzyme activity by binding to
the enzyme's allosteric site

Describe how enzymes function in anabolic and catabolic reactions

Hold reactants in their proper orientation and lower the energy
required for starting the reaction.

What factors affect enzyme activity

Drugs, environmental factors.
Temperature, pH, cofactors, temperature, how much substrate,
phosphorylation state, presence of inhibitors

Define feedback inhibition
(Both competitive and non-competitive inhibitors)

Competitive inhibitors, slow reactions by competing with a substrate
for the target enzyme's active site. Enzyme cannot carry out reaction
until competitive inhibitor leaves the active site, allowing substrate
to enter. Can be reversible.
Noncompetitive inhibitors, don't compete with substrate, decrease
enzyme activity by binding to the enzyme at a site other than the
active site. Deform enzyme structure so substrate cannot interact with
the active site. Can permanently inhibit an enzyme.
Feedback inhibition, enzyme form that slows down (or turn off)
biochemical pathways to help cells be efficient. Is reversible, cells
make a product to a point of sufficient quantities exist, then the
pathway is blocked from making any more. When product decreases to
less than what the cell needs, block goes away allowing the cell to
make more again. Ex amino acids and nucleotides.

Catabolism process of cell respiration: aerobic/anaerobic, fermentation

Cellular respiration, collection of reactions that extract energy
from foods using redox reactions and then transfer that energy into
bonds of ATP.
Aerobic or anaerobic, 6 glucose, glycolysis, intermediate step,
krebs cycle, electron transport chain. ATP
Fermentation, 6 glucose, glycolysis, fermentation, ATP plus end
products (alcohols, acids)

Diagram of an ATP molecule

Three phosphates, ribose, adenine

Summary of glycolysis

Extracts energy from complex carbohydrates (starches), disaccharides
(sucrose, lactose), simple sugars (mannose, fructose, glucose)
Ten reactions in two stages: energy investment state, payoff stage.
In the cytoplasm of prokaryotes and eukaryotes, does not require
energy. No carbons are removed
6 carbon sugar invest 2 ATP, 6 carbon glucose is split to make 2
pyruvic acids. NAD+ is reduced to NADH. Produces 4 molecules of ATP

Summary of intermediate step

Converts both molecules into acetyl-CoA (2 carbon molecule) and
releases carbon dioxide.

Summary of Krebs cycle

Formation of citric acid from oxaloacetic acid and acetyl-CoA.
Produces ATP and lots of reduced factors (NADH, FADH2). Runs once for
every acetyl-CoA made in intermediate step, therefor runs twice for
each glucose molecule entered. Every carbon is turned into carbon dioxide.

How/where do these processes occur in both prokaryotes and eukaryotes?
What is ATP synthase?

Glycolysis, cytoplasm of prokaryotes and eukaryotes
Intermediate step, in cytoplasm of prokaryotes and eukaryotes
Krebs cycle, cytoplasm of prokaryotes and matrix of mitochondria of eukaryotes
ATP synthase, enzyme in electron transport chain that captures
energy of protons, and uses it to recharge ADP to ATP. Found in
mitochondrial inner membrane of eukaryotes and plasma membrane of prokaryotes.

What are some various end products from anaerobic fermentation?
Why are we concerned about these products?

Homolactic fermentation, pyruvic acid made in glycolysis is only
reduced to lactic acid. Two ATP molecules that are gained are made in
glycolysis. Use this when oxygen is limited as during anaerobic exercise

How are lipids and proteins catabolized to produce ATP?

Lipids, lipase breaks lipids into glycerol and fatty acids. Glycerol
component is converted to DHAP and enter glycolysis. Fatty acids are
broken down, two carbons at a time, to acetyl-CoA molecules that can
enter krebs cycle via beta oxidation
Proteins, proteases and peptidases break proteins down into
peptides and then amino acids. Amino acids are recycled to make more
proteins. Must be stripped of amine group NH2 by deamination.
catabolized through krebs cycle.

How do bacteria use biosynthesis to make macromolecules?

Anabolic reactions that require ATP

What energy sources microbes use to make ATP?

Phototrophs, use energy from light to make ATP
Chemotrophs, energy found in chemical bonds of their nutrients to
make ATP
Mixotrophs, use variety of sources, and diverse in how they obtain energy.

How metabolic pathways and their products are used to identify bacteria.
Examples of metabolic tests to identify bacteria

Biochemical tests, amino acid catabolism tests, fermentation tests,
oxidase and catalase tests,

Chap 9

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Define pathogen

Include viruses, prions, bacteria, protozoans, helminths, and fungi.
Cause infectious diseases

Define opportunistic pathogen

Only cause disease when their host is weakened in some way

Define endemic

Infections detected in a population or region

Define pandemic

When a epidemic spreads to numerous countries

Define emerging pathogen

Newly identified agents (pathogens) that caused only sporadic cases,
but increasingly became more common

Define reemerging pathogen

Was under control due to prevention but is now resurfacing.

Define zoonotic disease

Spread from animals to humans

Define noncommunicable

Do not spread from person to person

Define contagious

Communicable diseases easily transmitted from one host to the next

Define signs

Indicators of disease that can be measured or verified, fever, rash.

Define symptoms

Sensed by patients and subjective rather than precisely measurable,
pain, fatigue, and nausea

Define latent diseases

Infected has no symptoms of the disease and is not contagious

Define chronic diseases

Slower onset and progression

Define acute diseases

Rapid onset and progression of a disease

Define noninfectious disease

Illnesses not directly caused by pathogens

Define susceptible host

Host that can develop the disease

Define obligate intracellular pathogen

Viruses and certain bacteria and protozoans, only replicate inside a
host cell and are impossible to grow as independent pure cultures.

Define reservoir

Animate or inanimate habitat where the pathogen is naturally found

Define source

Disseminates the agent from the reservoir to new hosts

Define endogenous source

Pathogen comes from the hosts own body

Define exogenous source

Source of an infecting pathogen that is external to the host

Define vector

Organisms (arthropods, rodents) that spread infectious agents to
other susceptible hosts

Define morbidity

Existence of diseases

Define prevalence rate

Measure of frequency that describes morbidity in a given population.
To calculate, take total number of disease cases during given time and
divide it by the total number of people in the defined population
during that same time

Define incidence rate

Number of new cases in a defined population during a defined time fram

Define duration

How long the infection lasts

Define epidemiology

Medicine that aims to understand and prevent illness in communities

Define HAI

Healthcare acquired infection, nosocomial infection. Infection that a
patient develops while receiving care in a healthcare setting

Define localized infection

Infection that is restricted to a specific part of the body

Define systemic infection

Infection widespread throughout the body

Define virulence factor

Pathogens use to stick/adhere

What are Koch's postulates

Four criteria used to evaluate what pathogen is the agent of a
particular disease
1. The same organism must be present in every case of the disease
2. Organism must be isolated from the diseased host and grown as a
pure culture
3. The isolated organism should cause the disease in question when
it is introduced (inoculated) into a susceptible host
4. The organism must then be re-isolated from the inoculated,
diseased animal

Table 9.2

Five stages of infectious disease
1. Incubation period
2. Prodromal phase
3. Acute phase
4. Period of decline
5. Convalescent phase

Figure 9.1 mechanisms of direct and indirect transmission

Direct: person to person, animal, environment, vertical
Indirect: Airborne, vehicle, vector (biological), vector (mechanical)

Describe 5 stages of infectious disease

1. Incubation period, time between infection and development of symptoms.
2. Prodromal phase, early symptoms develop
3. Acute phase, peak of the disease
4. Period of decline, replication of the infectious agent is
brought under control, symptoms start to resolve
5. Convalescent phase, patient recovers, some cases the pathogen is
kept latent in the patient

Epidemiological triangle, what can be done to stop the spread of infection

When host, agent, and environment overlap, there is possibility of
disease. Environmental factors, host factors, etiological agent
Taking away a link of the triangle can stop disease spread. Public
education, quarantine, vector control,

Explain the purview of the WHO and the CDC?
What is the MMWR?

CDC, Centers for disease control and prevention. WHO, world health organization

What is an HAI (nosocomial) Why are they a problem?
Examples of most common type of how to prevent them

Diseases that develop from a healthcare intervention. Direct and
indirect contact, contaminated medical devices and healthcare workers
hands are most common sources. Can be localized and systemic

Table 9.5 fig 9.10 describe actions that prevent/reduce HAI's

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What is the NNDSS? Public health surveillance?

NNDSS, National notifiable diseases surveillance system

Five examples of vaccine preventable diseases

Smallpox, polio, guinea worm