Comprehensive Overview of Human Anatomy and Physiology

anatomy

structure

physiology

function

What is homeostasis?

The process by which the body maintains a stable internal environment.

What does histology involve?

The study of tissues and cells using microscopy to visualize specific cells.

What is the anatomical position?

Standing erect with head level, eyes forward, hands at the side, palms forward, legs parallel, and feet flat.

prone

A horizontal body position with the face and upper body oriented upwards.

supine

A horizontal body position with the face and upper body oriented downwards.

What are body cavities?

Spaces that suspend internal organs, protecting, separating, and supporting them while allowing expansion and contraction.

What is the plasma membrane?

A selectively permeable barrier that controls the entry of ions, nutrients, and waste, and allows cell recognition.

What are the components of the plasma membrane?

Phospholipid bilayer with hydrophilic heads and hydrophobic tails, along with integral and peripheral proteins.

What is the function of ribosomes?

Sites of protein synthesis that can be free in the cytosol or bound to the rough endoplasmic reticulum.

What does the rough endoplasmic reticulum do?

Modifies and transports proteins, and is continuous with the outer nucleus membrane.

What is the role of mitochondria?

Generates ATP and has its own DNA, RNA, and ribosomes, allowing it to reproduce.

nucleus's function

Holds DNA for replication and protein synthesis; can be uninucleated, multinucleated, or anucleated.

What are the types of membranes in the body?

Cutaneous (skin), mucous (lines cavities open to outside), serous (lines internal organs), and synovial (lines joint cavities).

What is passive transport?

Movement of substances across the membrane without energy, including simple diffusion, facilitated diffusion, and osmosis.

What is active transport?

Movement of substances against a concentration gradient that requires ATP or energy.

What is tonicity?

The concentration of solutes in a fluid, affecting the movement of water across membranes.

What is a hypotonic solution?

A solution that is low in solutes compared to another solution.

What is a hypertonic solution?

A solution that is high in solutes compared to another solution.

What is an isotonic solution?

A solution with equal solute concentrations compared to another solution.

What happens to red blood cells in a hypertonic solution?

They lose water and may shrivel due to the higher solute concentration outside the cell.

What happens to red blood cells in a hypotonic solution?

They gain water and may swell or burst due to the lower solute concentration outside the cell.

What happens to cells in a hypertonic solution?

In a hypertonic solution, where there is a higher concentration of solutes outside the cell, water moves outside, leading to crenation of the cell.

What occurs in a hypotonic solution?

In a hypotonic solution, where there is a lower concentration of solutes outside the cell, water moves inside, causing the cell to swell and potentially burst.

What is negative feedback

process to reverse a change

How does positive feedback differ from negative feedback?

strengthens or enhances a stimulus to produce a larger change, resulting in rapid changes.

What are the vertical columns in the periodic table called?

The vertical columns in the periodic table are called groups.

What are the horizontal rows in the periodic table called?

The horizontal rows in the periodic table are called periods.

What does the atomic number represent?

The atomic number represents the number of protons in an atom.

Smallest unit of matter

Atom

What is atomic mass?

The number of protons and neutrons in an atom's nucleus.

In uncharged atoms, how do the number of protons and electrons compare?

They are equal.

What does the period number indicate in the periodic table?

The number of occupied electron shells.

What does the group number indicate in the periodic table?

The number of valence electrons.

What charge do electrons have?

A negative charge.

proton charge

A positive charge.

How many electrons can the 1st shell hold?

1 electron.

What is the maximum number of electrons that can occupy the 2nd to 20th shells?

Up to 8 electrons.

What are valence electrons?

Electrons in the outer shell that interact with chemical bonds.

What characterizes stable atoms?

They have a full valence shell and are unlikely to react.

What happens to unstable atoms?

They react with other atoms to become stable by losing or gaining electrons.

What is a molecule?

Two or more atoms joined by chemical bonds.

What is a compound?

Two or more different elements joined by chemical bonds.

What are ions?

Atoms that have gained or lost electrons.

What is the result of losing an electron?

The atom becomes positively charged.

What is the result of gaining an electron?

The atom becomes negatively charged.

What is an ionic bond?

A bond formed when one atom transfers electrons to another.

What is a covalent bond?

A bond formed when atoms share electrons.

What do organic compounds contain?

Carbon and hydrogen.

What are macromolecules?

Large organic molecules such as carbohydrates, lipids, proteins, and nucleic acids.

What is the pH range for acids?

pH < 7.

What is the pH of neutral solutions?

pH = 7.

What do acids produce when dissolved in water?

Aqueous hydrogen ions (H+).

What do alkalis produce when dissolved in water?

Aqueous hydroxide ions (OH-).

Buffers

To help neutralize blood when excess hydrogen or hydroxide is present.

What are prokaryotes?

Small, unicellular organisms without membrane-bound organelles.

What are eukaryotes?

Larger, multicellular organisms with membrane-bound organelles.

What is a virus?

A non-living entity that contains RNA or DNA within a protein capsule and infects host cells.

What are the modes of transmission for infections?

Contact, vehicle borne, vector borne, and vertical transmission.

What is sterilization?

The destruction or elimination of all microbes.

What is disinfection?

The elimination of most pathogens from inanimate objects, excluding bacterial spores.

What is the function of the integumentary system?

To cover and protect the body.

What are the main layers of the skin?

Epidermis, dermis, and hypodermis.

What is melanin?

A pigment that determines skin color and increases with UV exposure.

What is the role of keratin in the skin?

It provides water resistance.

What are the three types of barriers in the skin's defense system?

Chemical barriers (secretions and melanin), physical barrier (waterproof and continuity of skin), and biological barrier (macrophages).

What is the metabolic function of the skin related to vitamin D?

The skin produces vitamin D for calcium and phosphorus absorption, requiring 15 minutes of UV exposure per day.

How does the skin regulate body temperature?

Through sweat glands that secrete sweat, which cools the body.

What is the role of sebaceous glands in the skin?

They secrete sebum, which slows down bacterial growth and acts as a barrier.

What happens to skin as it ages?

Basal cell activity decreases, leading to thinning of the epidermis, increased injuries, decreased immune sensitivity, and reduced vitamin D production.

What is the function of the lymphatic system?

It drains excess fluid and proteins from tissues, defends against threats, transports fats and vitamins from the gut to the liver, and produces immune cells.

What are lymphocytes and macrophages?

Specialized white blood cells produced in bone marrow that seek and destroy foreign cells, proteins, and cancer cells.

What is the structure of lymph vessels?

They consist of lymphatic capillaries, vessels, trunks, and ducts, with overlapping endothelial cells allowing one-way fluid movement.

What are the primary organs of the lymphatic system?

Red bone marrow and thymus glands.

role of spleen

It filters blood, removes defective blood cells, and stores/releases blood and blood cells.

What is the role of lymph nodes?

They filter lymph, multiply B cells, and trap foreign matter for destruction by macrophages and T cells.

oedema

Excessive accumulation of interstitial fluid in tissue spaces, often due to increased blood pressure or obstruction of lymph flow.

What are antigens?

Anything capable of inducing an immune response, including microbes, proteins from other species, and transplanted tissues.

What are the two types of immunity?

Innate (non-specific) immunity, which is a general defense, and specific (adaptive) immunity, which targets specific antigens.

What are the first and second lines of defense in the immune system?

First line includes physical and chemical barriers (skin, mucous membranes), while the second line includes antimicrobial chemicals and immune cells.

What is the role of phagocytes in the immune response?

They 'eat' antigens, clean dead tissues, and are found in connective tissues and the bloodstream.

What are the key signs of inflammation?

Redness, heat, swelling, pain, and loss of function.

What is the role of natural killer cells?

They target and kill abnormal cells, particularly those infected by viruses.

What occurs during acute inflammation?

Localized response that limits infection chances, involves histamine release, and removes dead tissue.

What happens during a fever?

The hypothalamus resets temperature, raising it to destroy pathogens and promote healing.

What is the third line of defense in the immune system?

It involves specific responses to antigens using B and T cell lymphocytes, with memory formation after exposure.

What is the organization of the nervous system?

It consists of the central nervous system (brain and spinal cord) and the peripheral nervous system (all neural tissue outside the CNS).

What is the function of hair in the integumentary system?

Provides warmth, protection against physical trauma, and keeps out foreign particles.

What are the modifications of the epidermis?

Nails, which are densely packed epithelial cells made of hard keratin.

What is the role of sweat glands?

They regulate body temperature and remove waste.

What is the function of the cell body (soma) in a neuron?

It contains the nucleus and creates electrical impulses.

What are dendrites and their role in neuron function?

Dendrites are numerous and relatively short extensions that receive information from other neurons to pass onto the cell body.

What distinguishes grey matter from white matter in the brain?

Grey matter consists of neuron cell bodies and dendrites, while white matter consists of myelinated axons.

What is the role of the axon in a neuron?

The axon passes information away from the cell body and can be as long as 1 meter.

What is the myelin sheath and its significance?

The myelin sheath is a biological insulator made of a fatty substance that increases the speed of electrical impulses along axons.

What are the Nodes of Ranvier?

Gaps in the myelin sheath that facilitate faster electrical impulse transmission.

glia cells

cells that support, nurture, and protect neurons, maintain potassium balance, produce myelin sheath, and contribute to nerve regeneration

What is the resting membrane potential of a neuron?

The resting membrane potential is approximately -70mV, with the intracellular potential being more negative than the extracellular potential.

How does the sodium-potassium exchange pump function?

It actively transports sodium out of the cell and potassium into the cell, with a ratio of 3 sodium ions for every 2 potassium ions.