Respiratory and Circulatory Systems Review

Parts of the Respiratory System and Their Functions

• Nasal Cavity: Warms, moistens, and filters air.
• Pharynx: Passageway for air and food.
• Larynx:
  • Epiglottis: Closes off the windpipe during swallowing to prevent food from entering the airway.
  • Glottis: Contains vocal cords, facilitating sound production.
• Trachea: Conducts air to the bronchi.
• Bronchi: Main passageways into the lungs.
• Bronchioles: Smaller airways that lead to the alveoli.
• Alveoli:
  • Site of gas exchange with the circulatory system.
  • Oxygen enters the blood, and carbon dioxide is expelled.

Oxygen Carrying Cells

• Red Blood Cells (Erythrocytes):
  • Function: Carry oxygen throughout the body.
  • Require Hemoglobin:
  • Protein that binds oxygen.
  • Contains Iron: Facilitates oxygen binding.

Unique Blood Characteristics in Animals

• Some animals, like certain mollusks, have blue blood due to the presence of Cyanoglobin (copper-based).

Importance of Oxygen

• Engaged in Cellular Respiration: Essential for producing energy in cells.

Variations in Respiratory Systems

• Amphibians:
  • Lack diaphragm; use positive pressure to push air into lungs.
• Fish:
  • Utilize gills for extracting dissolved oxygen.
• Birds:
  • Possess air sacs and lungs for more efficient gas exchange during both inhalation and exhalation.
• Insects:
  • Utilize trachea for gas exchange, which limits body size due to inefficiency.

CO2 and Blood pH Connection

• Bicarbonate Buffer System:
  • CO2 in blood forms carbonic acid, which can dissociate into bicarbonate ions (HCO3-), buffering pH changes.
  • Increased CO2 leads to decreased pH (acidity), which triggers increased breathing to expel CO2.

Chronic Obstructive Pulmonary Disease (COPD)

• Definition: Chronic Obstructive Pulmonary Disease; includes conditions like emphysema and chronic bronchitis.
• Major Cause: Smoking is the leading cause.

Myoglobin in Animals

• Myoglobin:
  • Oxygen transport protein found in muscle tissues of aquatic mammals, aids in prolonged underwater swimming.

Circulatory System Components

• Veins: Carry deoxygenated blood back to the heart.
• Arteries: Carry oxygenated blood away from the heart.
• Capillaries: Small vessels for nutrient and gas exchange at the tissues.
• Pulmonary Circuit: Transports deoxygenated blood to lungs and oxygenated blood back to heart.
• Systemic Circuit: Carries oxygenated blood to body tissues and returns deoxygenated blood to the heart.

ECG Wave Parts

• P-Wave: Represents atrial contraction.
• QRS Complex: Represents ventricular contraction.
• T-Wave: Indicates heart resetting, involving electrolyte movements.

Blood and Plasma Differences

• Blood: Composed of cells (RBCs, WBCs, platelets) and liquid (plasma).
• Plasma: Liquid component containing dissolved substances like proteins and minerals.

Atherosclerosis

• Definition: Hardening of arteries due to plaque build-up from LDL cholesterol, leading to cardiovascular diseases.

Understanding Cholesterol Types

• LDL (Low-Density Lipoprotein):
  • Known as "bad cholesterol", deposits fats in tissues.
• HDL (High-Density Lipoprotein):
  • Known as "good cholesterol", retrieves fats from tissues back to the liver.

Hypertension & Related Conditions

• Hypertension: High blood pressure.
• Heart Attack (Myocardial Infarction): Tissue damage due to blocked coronary arteries.
• Stroke: Result of blood flow blockage in the brain.
• Angina Pectoris: Chest pain due to heart issues.

Unique Features of Arthropod Circulatory Systems

• Open Circulatory System: Hemolymph (equivalent of blood) bathes internal organs directly.

Circulatory System Variations in Animals

• Fish: Have a 2-chambered heart.
• Amphibians/Reptiles: Have a 3-chambered heart.
• Mammals/Birds: Have a 4-chambered heart, preventing mixing of oxygenated and deoxygenated blood for efficient metabolism.

Blood Cell Functions and Formation

• RBC: Transport oxygen.
• WBC: Function in immune protection:
  • T and B Cells: Adaptive immunity and antibody production.
  • Basophils: Release histamines to promote inflammation.
  • Eosinophils: Attack multicellular parasites.
  • Neutrophils: Engulf pathogens like macrophages.
  • Monocytes: Differentiate into various types of macrophages in tissues.

Lymphatic System and Function

• Function: Cleans and returns leaked fluids and substances from the circulatory system via lymph nodes.

Edema

• Definition: Swelling caused by fluid accumulation due to poor circulation.

Digestive System Overview

• Digestive Parts & Functions: All parts perform chemical and mechanical digestion except the esophagus.
  • Mouth: Begins starch digestion via salivary amylase.
  • Esophagus: Transports food to the stomach.
  • Stomach: Protein digestion via acidity and enzymes.
  • Small Intestine: Major site for digestion and absorption:
  • Duodenum: Bile from liver and enzymes from pancreas are introduced.
  • Jejunum: Continues digestion and absorption.
  • Ileum: Final absorption segment.
  • Large Intestine: Reabsorbs water and compacts waste.

Digestive Modifications in Animals

• Gizzard: Found in birds; grinds food with ingested stones.
• Cecum: Enlarged in hindgut fermenters for fiber fermentation (some eat feces).
• Foregut Fermenters: Ruminants with a 4-chambered stomach for fiber breakdown.

Diabetes Types Comparison

• Type 1 Diabetes:
  • Develops early, often autoimmune destruction of insulin-producing cells in the pancreas.
  • Requires insulin injections.
• Type 2 Diabetes:
  • Develops later, cells become insulin resistant.
  • Managed with lifestyle changes.

Hormonal Regulation of Blood Sugar

• Insulin: Hormone promoting sugar absorption from blood into cells to lower blood sugar levels.
• Glucagon: Hormone that signals liver to release sugar from glycogen to raise blood sugar levels.

Bariatric Surgery Options

• Sleeve Gastrectomy: Reduces stomach size to limit food intake.
• Gastric Bypass: Bypasses part of the stomach and intestine to limit nutrient absorption.
• Gastric Banding: Places a band around the stomach to reduce food intake.

Immune Response Differences

• Innate Immunity: Fast, non-specific response involving barriers and immune cells without lymphocyte involvement.

• Adaptive Immunity: Slow, specific response with memory cells; provides long-lasting immunity through antibodies. Vaccines enhance this response.

• Note: Some pathogens can mutate, complicating immunity development and vaccine effectiveness.