Unit 2 HBS

Neurological Diseases (Activity 2.1.8)

Devic's Disease (Neuromyelitis Optica, NMO): A rare autoimmune condition in which the immune system attacks the optic nerves and spinal cord.

Symptoms: Vision loss or blurred vision in one or both eyes; Weakness or paralysis in the limbs; Loss of bladder or bowel control; Pain or stiffness in the spine; Nausea and vomiting due to brainstem involvement

Epilepsy: A neurological disorder characterized by recurrent, unprovoked seizures caused by abnormal electrical activity in the brain.

Symptoms: Seizures (can vary from staring spells to convulsions); Temporary confusion or loss of awareness; Uncontrollable jerking movements in arms and legs; Psychological symptoms such as anxiety or déjà vu

Fibromyalgia: A chronic disorder involving widespread musculoskeletal pain, fatigue, and tenderness.

Symptoms: Widespread pain (often described as a constant dull ache); Extreme fatigue; Sleep disturbances or insomnia; Cognitive difficulties (commonly called "fibro fog"); Headaches and sensitivity to light or noise

Alzheimer's Disease: A progressive neurodegenerative disorder that leads to memory loss, cognitive decline, and personality changes.

Symptoms: Memory loss affecting daily life; Difficulty completing familiar tasks; Confusion with time or place; Trouble understanding visual images or spatial relationships; Changes in mood, personality, or behavior

Multiple Sclerosis (MS): A chronic autoimmune disease where the immune system attacks the protective sheath (myelin) around nerve fibers, disrupting communication between the brain and body.

Symptoms: Numbness or tingling in the limbs; Muscle weakness or spasms; Vision problems (blurred or double vision); Fatigue; Difficulty with coordination and balance

Parkinson's Disease: A progressive neurological disorder affecting movement and coordination due to the loss of dopamine-producing neurons.

Symptoms: Tremors, especially in the hands or fingers; Slow movement (bradykinesia); Muscle stiffness or rigidity; Impaired posture and balance; Speech changes (soft or slurred)

Charcot-Marie-Tooth Disease (CMT): A hereditary condition that damages the peripheral nerves, leading to muscle weakness and loss of sensation.

Symptoms: Weakness in the feet, legs, and hands; High foot arches or flat feet; Difficulty walking or frequent tripping; Numbness or reduced sensation in extremities; Muscle wasting in the lower legs (leading to a "stork leg" appearance)

Huntington's Disease: A genetic disorder causing progressive breakdown of nerve cells in the brain, affecting movement, cognition, and emotions.

Symptoms: Involuntary movements (chorea); Impaired coordination and balance; Difficulty swallowing or speaking; Cognitive decline (memory loss, difficulty planning); Mood swings, depression, or irritability

Lou Gehrig's Disease (Amyotrophic Lateral Sclerosis, ALS): A progressive neurodegenerative disorder affecting motor neurons, leading to muscle weakness and eventual paralysis.

Symptoms: Muscle weakness (especially in the hands, arms, and legs); Difficulty speaking or swallowing; Muscle cramps or twitching; Slurred speech; Breathing problems as the disease progresses

Endocrine System (Activity 2.2.1), including:

Types of hormones (Protein vs. Steroid)
Negative & Positive Feedback
Insulin & Glucagon
Diabetes (Type 1 & Type 2)

Protein Hormones	Steroid Hormones
Made of amino acids Cannot pass through the cell membrane; bind to surface receptors Work through secondary messengers (e.g., cAMP) Examples: Insulin, Glucagon, Growth Hormone	Derived from cholesterol Lipid-soluble; can pass through the cell membrane and bind to intracellular receptors Directly affect gene expression Examples: Estrogen, Testosterone, Cortisol

Negative Feedack

Positive Feedback

Maintains homeostasis by reversing a change.

Example: Regulation of blood glucose—when blood sugar rises, insulin is released to lower it; when it drops, glucagon is released to raise it

Amplifies a response until a specific event occurs.

Example: Oxytocin release during childbirth increases contractions until birth occurs.

Insulin

Glucagon

(produced by beta cells in the pancreas)
Lowers blood glucose by promoting glucose uptake into cells.
Stimulates glycogen formation in the liver.

(produced by alpha cells in the pancreas)

Raises blood glucose by breaking down glycogen into glucose in the liver.

Diabetes Type 1	Diabetes Type 2
Autoimmune disease where the immune system attacks insulin-producing beta cells in the pancreas. Results in little to no insulin production. Typically diagnosed in childhood or adolescence. Treatment: Insulin injections, monitoring blood sugar levels	Body cells become resistant to insulin or the pancreas doesn’t produce enough insulin. More common in adults but increasingly seen in younger individuals. Strongly linked to lifestyle factors (obesity, diet, lack of exercise). Treatment: Lifestyle changes, oral medications, sometimes insulin therapy.