Introduction to Human Physiology

These flashcards cover key concepts from the lecture notes on human physiology, focusing on homeostasis, tissue types, and physiological functions.

What is homeostasis in the human body?

Refers to the steady state of the internal environment, maintaining stable conditions such as body temperature, pH, sodium concentration, and water balance.

What are the three adaptations that penguins have to maintain body temperature in cold weather?

Anatomically, they have a thick layer of fat; functionally, they shiver to produce heat; behaviorally, they huddle together to reduce exposure to cold.

What are the four major types of tissues found in the human body?

Epithelial tissue, connective tissue, muscle tissue, and nervous tissue.

What role does epithelial tissue play?

This type of tissue covers body surfaces, lines internal organs, serves as a barrier against pathogens, and facilitates gas and nutrient exchange.

What is the function of connective tissue?

This type of tissue connects different types of tissues together, supports organs, and stores energy.

What distinguishes skeletal muscle cells from cardiac and smooth muscle cells?

Skeletal muscle cells are voluntary, have multiple nuclei, and show striations; cardiac and smooth muscle cells are involuntary and have different structures.

What system is responsible for detecting external stimuli in the human body?

The nervous system is responsible for detecting changes in the external environment.

What is the primary function of insulin?

Regulates blood glucose levels by facilitating the uptake of glucose into cells.

What do red blood cells do?

Red blood cells transport oxygen throughout the body using hemoglobin.

How does the endocrine system contribute to homeostasis?

This system regulates various hormonal responses that help maintain internal balance, such as blood glucose levels and water balance.

What is the difference between anatomy and physiology?

Anatomy refers to the structure or form of organisms, whereas physiology involves the functions of those structures.

What are the key variables maintained in homeostasis?

1. Fluid Levels: Concentration of solutes like \text{Ca}^{2+}, \text{Na}^+, and \text{K}^+ or glucose.

2. Blood pH: Must be maintained for biochemical processes.

3. Body Temperature: Maintaining heat even in extremes like -40 degrees Celsius.

What are the levels of biological organization?

1. Cells: Basic unit of life.

2. Tissues: Groups of similar cells.

3. Organs: Composed of multiple tissue types.

4. Organ Systems: Groups of organs with related functions.

5. Organism: Combined systems working together.

Distinguish between simple and stratified epithelia.

• Simple Epithelia: A single layer of cells (e.g., simple squamous).

• Stratified Epithelia: Multiple layers of cells (e.g., stratified squamous).

What is the function of cilia on epithelial cells in the airways?

HelpS clear debris by moving mucus through the respiratory tract.

What are the specialized functions of the different white blood cells (WBCs)?

• Neutrophils: Respond to bacterial infections.

• Lymphocytes: Respond to viral infections.

• Eosinophils: Respond to parasites.

What unique structures are found in cardiac muscle?

This muscle is striated, involuntary, and contains intercalated discs that promote synchronized contractions for pumping blood.

What are the primary components of a neuron?

• Dendrites: Receive signals.

• Axon: Conducts electrical impulses away from the cell body.

• Synaptic terminals: Release neurotransmitters to target cells.

What is Multiple Sclerosis (MS)?

An autoimmune disorder where the immune system destroys the myelin sheaths of axons, leading to disrupted electrical signal transmission.

What is the function of the renal system?

The renal system filters blood, maintains fluid balance, regulates solute concentrations, and eliminates waste through the production of urine.

What are the roles of ADH and Adrenaline?

• Anti-Diuretic Hormone (ADH): Promotes water reabsorption in the kidneys.

• Adrenaline (Epinephrine): Released during stress to increase blood pressure and energy availability.

What is the difference between conformers and regulators?

• Conformers: Internal conditions change to match the external environment.

• Regulators: Use internal mechanisms to maintain stable internal conditions despite environmental changes.

What are the components of a negative feedback loop?

1. Sensor: Detects changes (e.g., thermoreceptors).

2. Effector: Executes the response to return the system to its set point (e.g., sweat glands or muscles).