metabolism

7/17/2019 Metabolism

http://slidepdf.com/reader/full/metabolism-568e8d1e660a0 1/28

Overview of Energy and Metabolism

1. The food we eat, (carbohydrates, lipids,proteins, and Nucleic cids!, are our only

source of energy for doing the biological wor"

of cells.

#. ll molecules (nutrient molecules included!have stored (potential! energy in the bonds

between their atoms.

$. The energy the runs most biological %ystems

on earth comes from solar energy&. 'lants trap solar energy via the metabolic

reactions of 'hotosynthesis by producing these

molecules




Terms

Calorie: basic unit of measurement of energy in biologicalsystem. Indicated by a “c”

In human metabolism Calorie is really kilocalorie or 1,000calories. Indicated by a “C”

This calorie “C” is the amount of energy required to raise the

temerature to 1 kg of !ater 1 degree C.

The Caloric needs of most organisms is measured as "asal#etabolic $ate %"#$&




Terms

"#$ is the minimum resting energy e'enditures by ana!ake alert erson

()erage "#$: *0 C+hr or 1-0 C+day

If !e assume that a)erage amounts of carbohydrates, liid,and roteins are being catabolied !e can calculate a

ratio of /.- “C” er liter of 2 consumed.

"#$ in influence by age, gender, hysical condition, body!eight, and genes.



Three asic )ses of Nutrients

bsorbed by the *igestive %ystem

1. Energy for immediate use by cells to conducttheir normal Metabolic processes (Muscle

contraction, secretions, active transport!

#. %ynthesi+e structural or functional moleculesto repair and replace cells.(Mitosis and yto"inesis!

$. %torage as glycogen or fat for later use as

energy (nutrient reserves!



-- -iving Things from acteria to

umans onduct METO-/%M

Metabolism is the ability to ac0uire and use energy fromthe environment.

Metabolic processes are all the chemical reactions thatoccur in cells, tissues, organs, and organ systems.

Two inds of Metabolic 2eactions3

1. atabolism 4 brea"down of large molecules into simpleones to produce energy. (release energy!

#. nabolism 4 build large molecules from simplemolecules. (re0uires energy input!



T!o "asic 3inds of Chemical $eactions

found in "iological 4ystem



Metabolic Turnover and ellular T'

'roduction



arbohydrate Metabolism

(mino acid synthesis: Con)ert yru)ic (cid into an

(mino (cid requires a transamination

Transamination: 5yru)ic (cid 6 789 (mino (cid

lycogenesis: glucose glycogen

;iogenesis: glucose Triglyceride

lycogenolysis: glycogen glucose

luconeogenesis: lactic acid, amino acids, ortriglycerides glucose



4ummary of lucose #etabolism



4ummary of luconeogenesis



(T5 roduction from Carbohydrates

lycolysis

4ubstrates required: lucose, (T5, / (<5, and 7(<6

Intermediate $eactants: Glucose-6-phosphate, Fructose-1,6 bisphosphate

Products: 2 molecules of PyruvicAcid

2 ATP

2 NA!



2)er)ie! of Cellular resiration




=ormation of (cetyl>Co(

4ubstrates required: 5yru)ic (cid

7(<6

Coenyme (

5roducts: (cetyl>Co(

7(<8 C2




3reb?s cycle

4ubstrates required: 2'aloacetic (cid

(cetyl>Co(

7(<6

=(<

<5

Intermediate $eactants: Citric (cid




3reb?s cycle

5roducts: 2'aloacetic (cid

7(<8

=(<8

T5/ C2



2)er)ie! of the 3reb?s Cycle




@electron Transort Chain( series of 2'idati)e 5hoshorylation reactions

"#idatio$ % the removal of electro$sfrom a molecule a$d results i$ a

decrease i$ the e$er&y co$te$t of themolecule' (ecause most biolo&icalreactio$s i$volve the loss of hydro&e$atoms, they are calleddehydro&e$atio$ reactio$s'

)eductio$ % the opposite of o#idatio$*the additio$ of electro$s to amolecule, a$d results i$ a$ i$crease i$the e$er&y co$te$t of the molecule'




@lectron Transort Chain

4ubstrates required: 10 7(<8

=(<8

2

5roducts: 9 (T5

80



2)er)ie! of @lectron Transort 4ystem



4ummary of (T5 5roduction



'rotein Metabolism

*eamination3 removal of the amino group

(N#! leaving a acetyl molecule

Transamination3 dding an animo group to

pyruvic acid to produce any of thenonessential amino acids

'rotein %ynthesis3 'roduction of protein

molecule using an 2N model.'rotein catabolism3 brea"ing down a

protein into individual mino cids.



-ipid Metabolism

• -ipoproteins3 surrounding triglycerides withapoproteins to ma"e them more transportablein water – 5ery low6density lipoproteins (5-*-7s!

– -ow6density lipoproteins (-*-7s!

– igh6density lipoprteins (*-7s!

-ipolysis3 brea" down lipids

eta O8idation3 brea"ing a fatty acid into #carbon compounds

-ipogenesis3 formation of lipids from non6lipids



2)er)ie! of the $ole of the ;i)er in ;iid

#etabolism



4ummary of the Interconnection "et!een

Tissues and #etabolistic $eactions



#etabolic 2)er)ie!: The (bsorti)e 4tate



#etabolic o)er)ie!: the 5ostabsorti)e

4tate

metabolism

Documents