Homeostasis And Intracellular Metabolism

Question 1

Homeostasis - definition and mechanism

Answer 1

• Condition where internal environment remains stable and inside a certain interval → reach equilibrium
• Nervous system and endocrine system working together or separately

Question 2

Feedback systems

Answer 2

• Negative = fix equilibrium and most common
• Positive = accelerate change and often small part in bigger physiological process
• Feerforward mechanism = a warning which quickens start of process before changes occur

Question 3

Metabolism - carbonhydrates

Answer 3

• Converted into glucose and absorbed during digestion
• Main source for ATP synthesis
• Glucose stored in muscles and liver

Question 4

ATP SYNTHESIS

Answer 4

1. Glycolysis (anaerobi) = glucose → glucose-6-phosphate → 2 pyruvic acids + 2 ATP + electrons and hydrogen stored in coenzymes
   • In-between step = O2 + 2 pyrovic acids → 2 acetylCoA + CO2 (exhaled) + e- and H+ (into coenzyme) (if O2 not available it becomes lactate)
2. Kreb’s cycle (aerobic and in mitochondri) = 2 acetylCoA enters chemical chain circle and is broken down → 2 ATP + e- and H+ into coenzyme
3. Oxidative phosphorylation (aerobic and in the inner membrane of mitochondria) = coenzymes enter cycle → e- into electron transport chain + O2 + H+ → 34 ATP + H2O

Question 5

Metabolism- lipids

Answer 5

• Mostly broken down to triglycerides
• Can be stored or used to structure molecules: triglycerides → phospholipids + phosphate group

Question 6

Lipolysis

Answer 6

• Lipids → monoglycerides → glucose → Glycolysis
• Lipids → fatty acids → acetylCoA → Kreb’s cycle