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Learning objectives

  • Define and describe metabolism
  • Compare and contrast autotrophs and heterotrophs
  • Describe the importance of oxidation-reduction reactions in metabolism
  • Describe why ATP, FAD, NAD + , and NADP + are important in a cell
  • Identify the structure and structural components of an enzyme
  • Describe the differences between competitive and noncompetitive enzyme inhibitors

Part 1

Hannah is a 15-month-old girl from Washington state. She is spending the summer in Gambia, where her parents are working for a nongovernmental organization. About 3 weeks after her arrival in Gambia, Hannah’s appetite began to diminish and her parents noticed that she seemed unusually sluggish, fatigued, and confused. She also seemed very irritable when she was outdoors, especially during the day. When she began vomiting, her parents figured she had caught a 24-hour virus, but when her symptoms persisted, they took her to a clinic. The local physician noticed that Hannah’s reflexes seemed abnormally slow, and when he examined her eyes with a light, she seemed unusually light sensitive. She also seemed to be experiencing a stiff neck.

  • What are some possible causes of Hannah’s symptoms?

Jump to the next Clinical Focus box.

The term used to describe all of the chemical reactions inside a cell is metabolism ( [link] ). Cellular processes such as the building or breaking down of complex molecules occur through series of stepwise, interconnected chemical reactions called metabolic pathway s. Reactions that are spontaneous and release energy are exergonic reaction s, whereas endergonic reaction s require energy to proceed. The term anabolism refers to those endergonic metabolic pathways involved in biosynthesis , converting simple molecular building blocks into more complex molecules, and fueled by the use of cellular energy. Conversely, the term catabolism refers to exergonic pathways that break down complex molecules into simpler ones. Molecular energy stored in the bonds of complex molecules is released in catabolic pathways and harvested in such a way that it can be used to produce high-energy molecules, which are used to drive anabolic pathways. Thus, in terms of energy and molecules, cells are continually balancing catabolism with anabolism.

Diagram of metabolism. Catabolism: large molecules are broken down into small ones releasing energy. This is shown as a chain of 4 circles splitting into individual circles and Energy. The reverse process (using energy to connect the 4 circles) is anabolism. Anabolism: small molecules are assembled into larger ones, using energy.
Metabolism includes catabolism and anabolism. Anabolic pathways require energy to synthesize larger molecules. Catabolic pathways generate energy by breaking down larger molecules. Both types of pathways are required for maintaining the cell’s energy balance.

Classification by carbon and energy source

Organisms can be identified according to the source of carbon they use for metabolism as well as their energy source. The prefixes auto- (“self”) and hetero- (“other”) refer to the origins of the carbon sources various organisms can use. Organisms that convert inorganic carbon dioxide (CO 2 ) into organic carbon compounds are autotroph s . Plants and cyanobacteria are well-known examples of autotrophs. Conversely, heterotroph s rely on more complex organic carbon compounds as nutrients; these are provided to them initially by autotrophs. Many organisms, ranging from humans to many prokaryotes, including the well-studied Escherichia coli , are heterotrophic.

Questions & Answers

who is the father of microbiology
kasia Reply
Van Leewinhok
Albino
antonie van Leeuwenhoek
Ven.phumie
Antonio van Leeuwenhoek
uju
then Louis pasterur what?
Balu
He discovered fermentation process...
shamali
but he is also called father of microbiology..
Balu
I've always known Antonie as the father of microbiology
uju
Antonie Van Leeuwenhoek is known as the father of microbiology... he's firt who observed microorganisms under single lense microscope...
Samina
And he constructed the microscope himself
uju
Louis Pasteur father of modern microbiology
meenakshi
ya..right
Balu
yes that's true
uju
protista. are eukaryotes but they are not multicellular.. y?
Balu
protista are neither animal nor fungus not plants and it is nucleus are bound with the single cell
meenakshi
Right
RANJAN
how microbial proteins are used to diagnose infectious diseases
Gift Reply
microbes are cultured on industrial scale and then their secretions are extracted...I think that's called downstream processing
Chaitanya
in which language is the following sentence in omne vivum ex vivo
Chetan Reply
What are the five types of serological tests used to identify microorganism in the laboratory?
Prudence Reply
what is mycobacteria
Taslim Reply
it is bacterium of a group which include the causative agent tuberculosis and leprosy
meenakshi
moco means fungi so it is a fungi like bacteria.. it produces mycelium like structures..
Samina
what is gram staining
Nankya Reply
microbiology?
Bekka
It's technique to differentiate bacterial species.The method is discovered by Hans Christian Gram. The bacteria is differentiated as gram positive and gram negative on the basis of peptidoglycan layer which is present in cell wall. The gram positive have peptidoglycan layer.
shamali
What is study of morphology ? and it's classification
Maryam
taxonomy
Kamaluddeen
define the microbes
Saro
word microbes from microns.
Jayeeta
who is the father of microbiology?
Deborah
Antonie van Leeuwenhoek.
shamali
it is technique to stain the bacterial cell wall , and on this bacteria is classified into two broad group like gram positive e.g. streptococci ; staphylococci; pneumocci, cornybacteium diptheriae, clostridia, and gram negative eg salmonella shigella e.coli proteins klebsilla
Aryan
what makes a student to forget what he or she has been taught with easily and how can he or she cope up with it
Samson Reply
to be in touch with subject will help to cope up with the learning life long and also interest matters for subject
shriya
Constant review. And don't worry if you do forget something you always have the option to study it again. Each time you study a certain topic the more it make sense and the more it becomes something natural rather than brute memorization.
Abdi
the cause are many 1.lack of interest . 2. poor attitude to the subject. how can he cope up 1. falling in love with the subject . 2. making it part of you at all times and having determination
Ikilai
understanding the concept and relating whatever course of study with something in his/her day to day activities (i.e in which you are more conversant with in your life).
Kamaluddeen
how many types of cross matching method
umesh
which disease is caused by vicera zoster virus
Timaka Reply
chicken pox
Osuoha
Patients with disseminated herpes zostermay present with severe abdominal pain that results from visceral involvement of varicella-zoster-virus infection. In immunocompetent individuals herpes zoster usually is a localised illness, affecting the skin of one or two adjacent dermatomes.
Kamaluddeen
Actually, it is severe abdominal pain thanks
Osuoha
what causes inflammation of the lung?
Samson
what causes the fungi infection of the vigina
Estar Reply
what causes the fungi infection of the vagina?
Estar
poor hygiene of the area and unprotected sex with infected partner
Kamaluddeen
poor hygiene,some times having sex with infected person or when normal flora enters in the vagina
Ikilai
unprotected sex and poor hygiene are the major but keep in mind that there are some other minor causes also
Samson
what brings about dirt in blood
Sumaiyah Reply
So many factors might be the cause viz. Defects of blood capillaries and certain organs like the liver, the kidneys e.t.c
MOHAMMED
with the above any infection of the body easily enters the bloodstream.
MOHAMMED
there may be fevers which cause septicemia
Ikilai
even taking drug, and eating junk foods .
Ikilai
drinking contaminated water and taking drugs which contains chemical and afterwards they gets absorbed in yo the blood stream
Samson
write a essay about gene library's
anaparthi Reply
Structure of bacteria
Maggy Reply
Outline the classification of viruses according to morphology, nucleic acid, type of diseases, antigenic reaction
chilufya Reply
who is da father of microbiology
Mukomya Reply
Lucie pasture
Felicity
Father of microbiology is Anton von Leuuwenhoek
Anshika
mean Luice pasture the father of microbiology
Felicity
Luice pasture is the father of industrial microbiology
Anshika
who is the father of surgery
Talemwa
father of surgery is Sushruta
Agyekum
sushruta is the father of surgery
Ven.phumie
he Anthony van Lee wen hock
Ikilai
who is the father of medical microbiology
Naveen
he is Anthony van Lee wen hock
Ikilai
Anthony van Lee wen hook
Kamaluddeen
where would we be without microbes
Jessa Reply
nowhere because our body alone also contain billions of microbes.
Edward
in the dreams
Abid
Bangladeshi people's body contain thrice the amount of microbes than regular people.
IamTheMegaExploder
sure?
Kamaluddeen
yah
Kamran
why it was like that
Mمهazn
no where
Mukomya
cocci which are arranged in pairs are called?
umesh
diplococci
vijaya
Cocci are bacterias
Anshika
fimbriae is an organ of ?
umesh
what is the choma like vrius?
PRALHAD
Vibrio cholarea
Kamaluddeen
outline the classification of viruses
chilufya
Fimbriae z an organ of bacteria
Maggy
Antoni van Leeuwenhoek, the father of micro biology
Yang
Practice MCQ 5

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Source:  OpenStax, Microbiology. OpenStax CNX. Nov 01, 2016 Download for free at http://cnx.org/content/col12087/1.4
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