Anatomy and Physiology: Cell Biology, Homeostasis, and Body Organization

Vocabulary flashcards covering cell structure and function, cellular transport, signal transduction pathways, feedback loops, anatomical terminology, membranes, and tissue classifications based on the lecture notes.

Cell

The most basic structural and functional unit of life; the smallest part of an organism that is still capable of all life's processes.

Organelle

Specialized structures within the cell that work together to help the cell function.

Macromolecule

Key large biological molecules that make up all living things.

Nucleotide

The monomer of nucleic acids.

Fatty acid

The monomer of lipids.

Monosaccharide

The monomer of carbohydrates.

Amino acid

The monomer of proteins.

Enzyme

Biological catalysts; mostly proteins.

Catalyst

Molecules that speed up biochemical reactions by lowering the activation energy needed to get the reaction going without changing the reactants or products.

Active site

The highly specific location on an enzyme where substrates (reactants) bind.

Differentiation

The process of stem cells, or undifferentiated cells, undergoing specialization to become specific types of cells with different functions.

Cell membrane

Controls what goes in and out of the cell.

Centrioles

Organelles that play a key role in cell division and the anchoring of spindle fibers.

Cilia

Organelles that move fluid across the cell's surface.

Flagella

Organelle that moves the entire cell through extracellular fluid.

Nucleus

Organelle that holds the DNA that controls the activities of the cell.

Ribosomes

Organelles that make proteins.

Rough ER

Organelle that makes proteins.

Smooth ER

Organelle that makes lipids, performs chemical modifications, and stores $Ca^{2+}$.

Golgi apparatus

Organelle responsible for processing proteins to be sent out.

Vesicles

Organelles that transport proteins around and out of the cell.

Lysosomes

Organelles responsible for the breakdown of materials.

Vacuoles

Organelles responsible for storage.

Mitochondria

Organelle that is the site of cellular respiration.

Homeostasis

Stability of the internal environment and the mechanisms that maintain that stability.

Receptor

Sensory organ that receives the stimulus.

Stimulus

An action that evokes a response.

Effector

An organ that does the response.

Response

The effect, caused by the stimulus.

Feedback inhibition

When the output of a process is used as an input to control the behavior of the overall process itself, usually leading to inhibition of the process.

Passive transport

The movement of molecules across the cell membrane that doesn't require extra energy, moving down the concentration gradient.

Active transport

The movement of molecules across the cell membrane that does require extra energy, moving against the concentration gradient.

Hypertonic solution

A solution with a water concentration lower than the cell's cytoplasm.

Hypotonic solution

A solution with a water concentration higher than the cell's cytoplasm.

Isotonic solution

A solution with a water concentration identical to the cell's cytoplasm.

Ligand

Molecules that bind to other molecules (receptor proteins) for signaling purposes.

Signal transduction pathway

A sequence of events initiated by a signal that leads to a cellular response.

Inhibitor

Any molecule that blocks the normal ligand from binding, thus preventing communication along the signal transduction pathway.

Transduction

The passing along of the signal until the desired response is reached.

Phosphorylation

Addition of a phosphate group by kinases that changes a molecule's shape and contributes to transduction.

Dephosphorylation

Removal of a phosphate group by phosphatases that changes a molecule's shape and contributes to transduction.

Second messenger

A small molecule that serves as an intermediate between the receptor and the cascade of responses after.

Static equilibrium

An equilibrium state that is constant and unchanging.

Dynamic equilibrium

An equilibrium state that fluctuates above and below a constant state, where the overall rate of loss balances out with the overall rate of gain.

Positive feedback loop

A feedback mechanism where the output of a system intensifies the response, leading to amplification.

Negative feedback loop

A feedback mechanism where the output of a system causes a counter response to return to a set point, leading to stabilization.

Simple diffusion

Net movement of molecules from high to low concentration (e.g., $O_2$ and $CO_2$).

Facilitated diffusion

Uses a transport protein (channel or carrier) to aid in the movement of molecules from high to low concentration (e.g., $Ca^{2+}$ or glucose).

Osmosis

Diffusion of water from high to low concentration.

Molecular pumps

Uses energy to pump molecules through a protein channel against the concentration gradient (e.g., $Na^+/K^+$ pump).

Endocytosis

Uses energy and vesicles to move particles into the cell.

Exocytosis

Uses energy and vesicles to move particles out of the cell.

Autocrine signal

Chemical signal that affects the same cell that releases them.

Paracrine signal

Chemical signal that diffuses to nearby cells.

Juxtacrine signal

Chemical signal requiring direct contact between the signaling cell and the receiving cell.

Hormones

Chemical signal that travels to distant cells.

Lateral

Anatomical term meaning away from the midline of the body; on the outer side of.

Intermediate

Anatomical term meaning in between.

Proximal

Anatomical term meaning closer to the point where a limb attaches to the body trunk.

Distal

Anatomical term meaning farther from the point where the limb attaches to the body trunk.

Superficial

Anatomical term meaning toward or at the body surface.

Deep

Anatomical term meaning away from the body surface.

Body planes

Flat surfaces used to divide the body into different sections.

Sagittal plane

Vertical plane that divides the body into left and right sections.

Midsagittal plane

A sagittal plane that crosses through the midline of the body.

Parasagittal plane

A sagittal plane that does not cross through the midline of the body.

Frontal (coronal) plane

Vertical plane that divides the body into anterior and posterior sections (front and back).

Transverse (cross section) plane

Horizontal plane that divides the body into superior and inferior sections (above and below).

Cutaneous membrane

Skin, the covering of the body's surface.

Mucous membrane

Mucosae; lines all body cavities that open to the outside of the body.

Serous membrane

Serosa; lines ventral body cavities that are closed as well as covers many organs.

Parietal membrane

Type of serous membrane that lines the body cavity.

Visceral membrane

Type of serous membrane that covers internal organs.

Meninges

The membrane that covers the brain and spinal cord in the dorsal body cavity.

Tissues

Groups of cells that are similar in structure and work together for a common function.

Organ

A distinct structure made up of at least $2$ different types of tissues.

Exocrine glands

Externally secreting glands (e.g., sweat).

Endocrine glands

Internally secreting glands (e.g., hormones).

Neuron

Highly specialized nerve cells that make up nervous tissue and generate and conduct nerve impulses.

Thermoregulation Feedback Loop

A negative feedback loop maintaining human body temperature at $37^\times\text{C}$ ($98.6^\times\text{F}$) using the hypothalamus in the brain as a receptor, with sweat glands, capillaries, and muscles acting as effectors.

Signal Transduction Pathway Diagram

A visual model of a signaling pathway showing a signal molecule binding to a cell membrane receptor in extracellular fluid, triggering signal transduction across the cytoplasm to produce a cellular response.

Connective Tissue Classification Flowchart

A structural diagram categorizing Connective Tissue into Connective tissue proper (Loose and Dense), Cartilage (Hyaline, Elastic, Fibrocartilage), Bone (Compact, Spongy), and Blood.