3rd Tri topics - respiratory, excretory, endocrine, nervous, cells and digestive

Respiratory System Functions

• Exchanges gases (oxygen and CO2)
• Produces vocal sounds and sense of smell
• Removes waste gases, including carbon dioxide, from the body when exhaling
• Regulates blood pH
• Protects airways from harmful substances and irritants

Respiratory System Parts

• Nose
• Trachea (windpipe)
• Bronchi tubes
• Lungs
• Bronchioles (smaller tubes)
• Alveoli (tiny air sacs)
• Diaphragm

Nose and Nasal Cavity

• Bones and cartilage support the nose
• Two openings (nostrils) clean the air with hairs and layers of mucus
• Air is warmed and moistened in the nose
• Nasal cavity is a hollow space behind the nose
• Nasal septum is a bone that divides the nose

Pharynx and Epiglottis

• Pharynx is a tube-like passageway used by food, liquid, and air
• Epiglottis is a flap of tissue that closes to cover the trachea during swallowing to prevent food from entering the lungs

Larynx

• Enlargement at the top of the trachea that houses vocal cords (voice box)

Respiratory System Illnesses

• Cystic Fibrosis: hereditary disease causing mucus to clog lungs, making it difficult to breathe and causing infections
• Laryngitis: inflammation of the larynx causing hoarseness or loss of voice
• Hyperventilation: increased breathing rate due to anxiety or panic, leading to low CO2 concentration
• Hypoxia: disease characterized by a lack of oxygen in the body's tissues and vital organs
• Asphyxia: condition of severely deficient oxygen supply to the body
• COPD (Chronic Obstructive Pulmonary Disease): obstruction of the airways, often caused by smoking
• Emphysema: gradual degeneration of the inner wall of the air sacs, reducing the surface area of the lungs
• Lung Cancer: abnormal cell growth in the lungs
• Pneumonia: inflammation of the airspaces in the lungs, usually caused by infections
• Tuberculosis: infectious and inflammatory lung disease caused by bacteria
• Asthma: inflammation of the bronchial tubes with increased production of sticky secretions

Keeping the Respiratory System Healthy

• Do not smoke
• Exercise daily to increase lung capacity
• Eat a diet rich in nutrients
• Drink plenty of water to help thin mucus in the lungs
• Practice good oral hygiene to prevent lung diseases

Excretory System

• Removes excess water, urea, CO2, and other wastes from the blood
• Maintains homeostasis, a state of balance among all body systems

The Skin

• Excretes excess water, salts, and a small amount of urea in sweat
• Removes waste through perspiration (the process of sweating)

The Kidneys

• Filter out excess water and urea
• Remove waste by urination (the discharge of urine from the body)
• Every drop of blood in the body is filtered by the kidneys about 300 times per day
• Regulate the amount of water needed to maintain in the body (homeostasis)

Kidney Function

• Eliminate urea, minerals, and excess water
• Filter wastes and excess water from the blood

Urinary System

• Kidneys filter blood, producing urine
• Ureters transport urine from kidneys to the urinary bladder
• Urinary bladder stores urine until it is released through the urethra

Waste Excretion

• Skin: sweat, salt, and small amounts of urea
• Lungs: carbon dioxide and water
• Kidneys: urine and urea
• Large intestine: feces

Kidney Failure

• When kidneys can no longer cleanse the blood and maintain homeostasis
• Symptoms: swelling, weakness, fatigue, feeling cold, shortness of breath, changes in urination, itchy dry skin, sore legs, loss of taste, and vomiting
• Treated through hemodialysis and kidney transplant

Caring for the Excretory System

• Drink plenty of water
• Have a balanced diet
• Eat plenty of fruits and vegetables
• Exercise regularly
• Practice proper hygiene
• Do not hold back the need to urinate

The Endocrine System

• The endocrine system and nervous system work together to help maintain homeostasis or balance in the body.
• The hypothalamus is a collection of specialized cells located in the brain, and is the primary link between the two systems.

Pituitary Gland

• The pituitary gland is a small, pea-sized gland located in the brain.
• It controls the functions of many other endocrine glands.
• The pituitary gland produces several hormones, including growth hormone (GH) that stimulates body cells to grow and reproduce.
• It also helps control blood pressure and water balance.

Other Endocrine Glands

• Thyroid gland: produces hormones that regulate growth, development, and metabolism.
• Parathyroid gland: produces hormones that regulate calcium levels in the blood.
• Adrenal gland: produces steroid hormones that help regulate the body's stress response and maintain homeostasis.
• Pancreas: produces hormones that regulate blood sugar levels.
• Ovaries (in females) and testes (in males): produce hormones that regulate sexual function and development.
• Thymus: produces hormones that regulate the immune system.
• Pineal gland: produces hormones that regulate sleep and wakefulness.

Hormones and Health

• Hormones regulate growth, development, mood, tissue function, metabolism, and sexual function.
• Hyposecretion or hypersecretion of any hormone can be harmful to the body.
• Controlling the production of hormones can treat many hormonal disorders in the body.

Endocrine System Diseases

• Goiter: a condition where the thyroid gland becomes enlarged due to a lack of iodine in the diet or an over- or underproduction of thyroid hormone.
• Hypothyroidism: a condition where the thyroid gland does not produce enough thyroid hormone, leading to a slow metabolism.
• Hyperthyroidism: a condition where the thyroid gland produces too much thyroid hormone, leading to a fast metabolism.
• Hashimoto's disease: an autoimmune disorder that can cause hypothyroidism or hyperthyroidism.
• Addison's disease: a condition where the adrenal glands do not produce enough cortisol, leading to low blood pressure and increased pigmentation.
• Diabetes insipidus: a condition where the body produces too much urine and is very thirsty.
• Diabetes mellitus: a condition where the body does not produce enough or respond normally to insulin, leading to high blood sugar levels.

Nervous System Overview

• The nervous system is the body's communication and control system.
• It consists of two divisions: the Central Nervous System (CNS) and the Peripheral Nervous System (PNS).

Central Nervous System (CNS)

• Made up of the brain and spinal cord.
• Analyzes information and makes decisions.

Peripheral Nervous System (PNS)

• Made up of nerves that branch from the brain and spinal cord.
• Collects information needed to make decisions.

Nerve Structure

• Nerves are bundles of fibers composed of neurons that transmit information from one body part to another.

Neurons

• Basic working units of the nervous system.
• Information messengers that receive and send electrical messages called impulses.

Brain Regions

• Cerebrum: controls voluntary movements, thinking, and decision-making processes.
• Cerebellum: controls physical coordination.
• Brain stem: helps sort messages, channels them to the correct part of the brain, and controls breathing rate, heart rate, and blood pressure.

Spinal Cord

• A column of nerve tissue that runs from the base of the skull down the center of the back.

Sensory Receptors

• Gather information from the environment.

Stimulus and Reflex Actions

• Stimulus: any change in the internal or external environment.
• Reflex actions: automatic and rapid responses to stimuli.

Nervous System Functions

• The spinal cord connects the CNS to the PNS.
• Impulses travel back and forth between the brain and muscles through the PNS.

Peripheral Nervous System Divisions

• Sensory Division: receives information from sensory receptors.
• Motor Division: sends impulses to muscles or glands.

Motor Division Components

• Somatic Nervous System: motor responses in skeletal muscles under conscious control.
• Autonomic Nervous System: motor responses not under conscious control.
  • Parasympathetic: normal conditions.
  • Sympathetic: times of stress.

Path of Message

• Nerve impulses follow a path from sensory organs to the spinal cord, then to the brain, and finally to the parts of the body to carry out required actions.

Health Problems Associated with the Nervous System

Meningitis

• Inflammation of the meninges covering the brain or spinal cord caused by bacteria.
• Symptoms: severe headache, slow respiration, low pulse rate, and unconsciousness.
• Treatment: antibiotics and vaccination.

Concussion

• Traumatic brain injury caused by a blow to the head or body.
• Symptoms: difficulty speaking, numbness, weakness, and temporary blindness.

Stroke

• Condition caused by a blockage in the arteries, cutting off oxygen supply to the brain.
• Symptoms: difficulty speaking, numbness, weakness, and temporary blindness.
• Prevention: low-fat diet and medical treatment.

Alzheimer's Disease

• Caused by abnormal tissue in the brain, leading to confusion, memory loss, and restlessness.
• No known treatment, but good nutrition may slow its progress.

Parkinson's Disease

• Caused by damage to brain cells, leading to symptoms like mask-like face, trembling hands, and loss of control.
• Treatment: correcting imbalance in brain substances.

Epilepsy

• Condition involving damage to neurons, causing sudden convulsions, abnormal muscle jerks, and seizures.
• Treatment: surgery and medication.

Poliomyelitis

• Disease caused by polio virus, attacking nerve cells and causing headache, sore throat, vomiting, and muscle weakness.
• Prevention: polio vaccine and rest.

Amnesia

• Condition caused by head injuries, physical trauma, shock, or repression, leading to temporary or permanent memory loss.
• Treatment: occupational therapy.

What is a Cell?

• Cells are the basic structures of all living organisms
• Cells provide structure for the body, take in nutrients from food, and carry out important functions
• Cells group together to form tissues, which in turn group together to form organs, such as the heart and brain

What are Organelles?

• Organelles are specialized structures that perform various jobs inside cells
• Organelles carry out tasks such as making proteins, processing chemicals, and generating energy for the cell
• The term "organelle" means "little organs" and serves specific functions to keep a cell alive

Discovery of Cells

• The cell was first discovered by Robert Hooke in 1665 using a compound microscope
• Hooke observed a multitude of tiny pores in a thin slice of bottle cork, which he named "cells" due to their resemblance to small rooms

Cell Theory

• The cell theory states that:
  • All organisms are made up of one or more cells
  • All life functions of an organism occur within cells
  • All cells come from preexisting cells
• Proponents of cell theory include Theodor Schwann, Matthias Jakob Schleiden, and Rudolf Virchow

Proponents of Cell Theory

• Theodor Schwann: "Cell is the basic unit of Life"
• Matthias Jakob Schleiden: "All living organisms are made up of cells"
• Rudolf Virchow: "All cells come from preexisting cells"

Cell Division

• Cell division is the process in which a parent cell divides, eventually giving rise to new daughter cells
• It is the means used by multicellular organisms to grow, replenish, and reproduce

Life of a Cell

• Millions of cells in the body die every minute but are constantly being replaced through the cell cycle
• The process of cell cycle is spent growing, with a small portion of time taken to divide

Chromosomes

• Chromosomes are structures found inside the nucleus of a cell, made up of proteins and DNA organized into genes
• Humans have 23 pairs of chromosomes, with 22 pairs being autosomes and 1 pair being sex-determining
• Chromosomes are copied in the cell cycle, and each chromosome has two identical "sister" chromatids

Mitosis

• Mitosis is a process where a single cell divides into two identical daughter cells
• The major purpose of mitosis is for growth and to replace worn-out cells
• The four phases of Mitosis are Prophase, Metaphase, Anaphase, and Telophase

Meiosis

• Meiosis is a process where a single cell divides twice to produce four cells containing half the original amount of genetic information
• The purpose of meiosis is to produce gametes, the sperm and eggs, with half of the genetic complement of the parent cells

Digestive System

• The purpose of the digestive system is to break down food into nutrients that can be used by the body's cells.
• Food is the fuel that keeps the body working.

Parts of the Digestive System

• Mouth
• Esophagus
• Stomach
• Small Intestine
• Large Intestine
• Liver
• Gallbladder
• Pancreas

Digestion

• Mechanical digestion involves tearing, crushing, and mashing food.
• Chemical digestion involves enzymes breaking down food into nutrients.

Path of Food Through the Body

Mouth

• Food is shredded by teeth and mixed with saliva.
• Saliva breaks down starches into simple sugars and softens the food.
• The tongue pushes the food (bolus) down the esophagus.

Esophagus

• Muscles in the esophagus push the bolus down into the stomach.
• Peristalsis, a series of wavelike muscle contractions, helps move food through the digestive tract.

Stomach

• Food is churned and mixed with digestive juices (enzymes and acid) to break down proteins.
• The bolus becomes a thick liquid called chyme.

Small Intestine

• Partly digested food mixes with chemicals from the pancreas and liver.
• Digested food passes into the bloodstream through the villi in the small intestine walls.

Large Intestine

• The large intestine absorbs water and stores waste until it can be eliminated from the body.

Rectum/Anus

• Solid waste (feces) is eliminated from the body through the rectum.

Accessory Organs in Digestive System

• Liver: produces bile that breaks down fat.
• Gallbladder: stores bile and releases it to the small intestine when needed.
• Pancreas: produces enzymes that flow into the small intestine to help neutralize stomach acid.

Functions of the Digestive System

• Ingestion: taking in food through the mouth.
• Propulsion: movement of food throughout the alimentary canal.
• Digestion: breakdown of food into simple forms that can be absorbed by the body's cells.
• Absorption: taking in of nutrients from the digested food into the cells of the body.
• Defecation: excretion or release of waste materials that are not absorbed by the body.

Disorders of the Digestive System

GERD

• Gastroesophageal reflux disease, or chronic acid reflux.
• Acid-containing contents in the stomach leak back up into the esophagus, irritating the lining.

Hepatitis

• Hepatitis B: caused by the virus HBV, spread through contact with an infected person's blood, semen, or body fluid.
• Hepatitis C: caused by the virus HCV, spread through contact with an infected person's blood, semen, or body fluid.

Crohn's Disease

• A type of inflammatory bowel disease (IBD).
• Causes inflammation of the digestive tract, leading to symptoms such as crampy abdominal pain, fatigue, and weight loss.

IBS (Irritable Bowel Syndrome)

• Muscles in the bowel wall may contract too forcefully or too weakly, leading to symptoms such as abdominal pain, diarrhea, and constipation.

Stomach Ulcers

• Peptic ulcers affect the stomach and the upper part of the small intestine (duodenum).
• Ulcers in the stomach are also called stomach ulcers or gastric ulcers.