Anatomy and Physiology Chapter 25 - Intro to the Cellular Metabolism

metabolism

the sum of all chemical and physical changes in the body; everything a cell does requires energy and mainly access energy by breaking bonds of glucose molecules

catabolic pathways

release energy by breaking down complex molecules into simpler compounds

anabolic pathways

consume energy to build complex molecules from simpler ones

exergonic

releases energy

endergonic

absorbs energy

ATP

composed of a nucleotide with 3 phosphate groups and has a lot of potential energy held between the last 2 phosphate groups; the high energy bond between the last 2 phosphate groups make ATP unstable

NADH and FADH2

coenzymes that accept and transfer electrons

reduced state

energized state that can provide energy for the electron transport chain

NAD+ to NADH/FAD to FADH2 is…

reduction

NADH to NAD+/FADH2 to FAD is…

oxidation

electron transport chain

set up H+ gradient to do work; has an arrangement of coenzymes within the membrane; as 1 molecule is oxidized, the next is reduced

cellular respiration equation

C6H12O6 + 6 O2 = 6 CO2 + 6 H2O + 36 ATP

cellular respiration

the process by which our bodies produce cellular energy from chemical energy

3 reasons why glucose is the preferred molecule for catabolism

1. small and soluble

2. easily mobilized

3. others have to first be broken into things that look like glucose

3 steps of cellular respiration

1. glycolysis

2. citric acid cycle

3. oxidative phosphorylation

glycolysis

occurs in the cytoplasm and produce 2 pyruvate, 2 NADH, and 2 ATP

citric acid cycle

occurs in the mitochondrial matrix of a mitochondrion and results in 2 ATP, 8 NADH, 2 FADH2, and 6 CO2

oxidative phosphorylation

occurs in the inner mitochondrial membrane, relies on O2 as the last acceptor in the ETC, and results in 28 ATP and 6 H2O

proton gradient (proton motive force)

H+ ions are unequally distributed across the inner membrane of the mitochondria and is established by active transport of electrons and the passive transport fuels ATP synthesis

electron transport chain and chemiosmosis

has 4 complexes (respiratory complexes) where NADH is deposited at Complex I and FADH2 is deposited at Complex II; fewer H+ move across the membrane after Complex II resulting in fewer ATP produced; H+ ions go through ATP synthase, generating ATP by making the rotator spin

lactic acid fermentation

anaerobic respiration where glycolysis and fermentation occurs to produce 2 lactate molecules; moved to the liver/kidneys to make glycose/glycogen

2 ways of catabolism of lipids

1. use of glycerol from a triglyceride (fatty acid chains broken to make acetyl-CoA (enters citric acid cycle like normal) via beta oxidation; NADH and FADH2 also made for the ETC)

2. beta oxidation (9 acetyl-CoA from 1 fatty acid chain and 120 net ATP from 1 fatty acid chain)

2 ways of catabolism of amino acids

1. transamination (amino group transferred to a keto acid so that the keto acid can go through the citric acid cycle

2. deamination (removal of the amino group, producing NH4+ ion, but this ion is toxic and must go through the urea cycle to produce relatively harmless urea

glucogenesis

requires the most energy and more difficult, creates glycogen storage in liver and muscles

amination

uses an NH4+ ion to make amino group, forming amino acid; bady can only build 10 of the 20 essential amino acids

lipogenesis

glycerol made from and intermediate glycolysis process (acetyl-CoA)