cell molc lesson 11

synthesis of ATP by oxidative phosphorylation

energy from breakdown of nutrients used to energize electrons → electrons tunnel through transmembrane proteins → proton gradients → drive ATP synthase → ATP production  (occurs in inner mitochondrial membrane)

mitochondria structure

inner and outer membrane, intermembrane space → inside is matrix

glycolysis

uses glucose to form the pyruvate → pyruvate in mitochondrial matrix → critic acid cycle forms NADH and FADH2 → go through ETC → generates ATP (occurs in cytoplasm)

ROS (reactive oxygen species)

both free radical and non-free radical oxygen intermediates, cause membrane damage, protein damage, and DNA damage

ROS major sites of production

mitochondria, peroxisomes, phagocytes

ROS neutralization

• SOD: free radical to hydrogen peroxide 

• Catalase: turns into water

• GPx: turns into water

necrosis

accidental cell death, produces local inflammation and involves large groups of neighboring cells

apoptosis

programmed cell death, no inflammation and neighboring cells remain healthy

four steps of phagocytosis

1. attachment (find me)

2. engulfment (eat me)

3. fusion with lysosome

4. degradation

phagocytosis

immune cells engulf bacteria/dead cells

find me signal/receptor

signal: ATP, UDP, fractalkine; phagocyte receptor: P2X, P2Y, fractalkine receptor

fusion with lysosome

phagosome + lysosome → phagolysosome

degradation

breakdown by hydrolases and ROS

respiratory burst

a rapid increase in the production of ROS during phagocytosis