Homeostasis

• What is the role of insulin in blood sugar regulation?

  Facilitates glucose uptake by cells
• What is the control center for body temperature regulation and its function?

  • Located in the brain
  • Analyzes information from sensors
  • Decides on appropriate response
• What can happen if homeostasis is disrupted?

  It can lead to health problems like heat stroke
• What role does the sensor play in a negative feedback system for body temperature?

  1. Detects the stimulus (body temperature exceeds 37°C)
  2. Sends information to the control center
• What are the components of feedback systems in homeostasis?

  Sensors, control centers, and effectors
• What does negative feedback do?

  Brings conditions back to the set point
• What are the key components of homeostasis in the body?

  • Internal conditions remain stable
  • Mechanisms activated by changes
  • Examples: sweating, shivering
• What happens when blood sugar levels drop?

  Sensors signal the pancreas to release insulin
• What internal conditions does homeostasis regulate?

  • Body temperature (around 37°C)
  • Blood pH (narrow acidity range)
  • Blood sugar (glucose levels)
• What is the initial response of the body when acid-base homeostasis is disturbed by either acidosis or alkalosis?

  Stimulation of brain and arterial receptors
• How does blood CO₂ affect pH in acidosis?

  CO₂ decreases, causing pH to increase
• How does the level of carbonic acid (H₂CO₃) change during respiratory compensation?

  It decreases in acidosis and increases in alkalosis
• What occurs when temperatures exceed the optimal point for enzymes?

  Denaturation occurs, reducing enzyme activity
• What happens to enzymes at extreme temperatures?

  They can denature and lose functionality
• What is denaturation in the context of enzymes?


  Loss of enzyme structure and function
• How does blood CO₂ affect pH in alkalosis?


  CO₂ increases, causing pH to decrease
• What are the two main disturbances of acid-base homeostasis?

  Acidosis and alkalosis
• How does substrate concentration affect enzyme activity?

  Increased substrate enhances activity up to saturation
• What are the compensatory mechanisms in the body for alkalosis?

  • Decrease in respiration rate
  • Increase in blood carbon dioxide (CO₂)
  • Increase in blood carbonic acid (H₂CO₃)
  • pH decreases towards normal
• What are the factors affecting enzyme action?

  Temperature, pH, substrate concentration, enzyme concentration
• What happens when blood pH drops too low?

  Brain and arterial receptors detect acidosis
• What are the compensatory mechanisms in the body for acidosis?

  • Increase in respiration rate
  • Decrease in blood carbon dioxide (CO₂)
  • Decrease in blood carbonic acid (H₂CO₃)
  • pH increases towards normal
• What limits the reaction rate when enzyme concentration increases?

  Limited substrate availability can restrict rate
• What system does homeostasis use to maintain optimal pH?

  Buffer system
• What is the name of the layer surrounding the cell?

  Plasma membrane
• What triggers the positive feedback mechanism in blood clotting?

  A small cut triggers more clotting
• What are the two mechanisms that the body uses to regulate temperature?

  • Heating mechanisms (shivering)
  • Cooling mechanisms (sweating)
• What is the process when temperature receptors detect cold?

  1. Temperature receptors detect cold
  2. Brain signals muscles to shiver
  3. Shivering generates heat
  4. Body temperature increases
• What are the key components of the cell membrane?

  • Phospholipid bilayer
  • Proteins (integral and peripheral)
  • Cholesterol
  • Carbohydrates (glycoproteins and glycolipids)
• How does a signaling molecule interact with an intracellular receptor?

  • Signaling molecule binds to intracellular receptor
  • This activates the receptor and triggers a response inside the cell
  • The response could involve changes in gene expression, metabolism, or cell behavior
• What is the name of the structure inside the cell that contains the DNA?

  Nucleus
• What is the main coordination centre in vertebrates?

  The brain
• What effect does positive feedback have in control systems?

  It amplifies change
• What are the differences between the nucleus and cytoplasm in a cell?

  Nucleus:

  • Contains DNA and controls cell activities
  • Separated from cytoplasm by nuclear envelope

  
  

  Cytoplasm:

  • Gel-like substance surrounding the nucleus
  • Site of many cellular processes like metabolism
• What effect does negative feedback have in control systems?

  It counteracts change
• What are the main functions of the different lobes of the brain?

  • Frontal lobe: Motor control, concentration, planning, problem solving
  • Parietal lobe: Sensory processing, spatial awareness
  • Temporal lobe: Hearing, language, memory
  • Occipital lobe: Vision
  • Cerebellum: Coordination, balance
• What is the name of the fluid surrounding the cell?

  Extracellular fluid