Anatomy and Cell Biology Practice Flashcards

Vocabulary flashcards covering human anatomy levels of organization, directional terminology, planes, body cavities, cell membrane transport mechanisms, organelles, and cell division.

Anatomical Position

Standard frame of reference in which a person stands erect with feet flat on the floor, arms at sides, and palms, eyes, and face facing forward.

Supine

Body or forearm position where palms face forwards or upwards and the radius and ulna are parallel.

Prone

Body or forearm position where palms face rearward or downward and the radius and ulna are crossed.

Sagittal Plane

An imaginary flat surface that passes through the body vertically, dividing it into right and left halves.

Frontal Plane

Also called the coronal plane, an imaginary surface that divides the body into front (anterior) and back (posterior) portions.

Transverse Plane

Also called the horizontal plane, an imaginary surface that divides the body into upper (superior) and lower (inferior) portions.

Ventral

Directional term meaning toward the front or belly.

Dorsal

Directional term meaning toward the back or spine.

Proximal

Directional term meaning closer to the point of attachment or origin.

Distal

Directional term meaning farther from the point of attachment or origin.

Axial Region

Body region consisting of the head, neck, and trunk.

Appendicular Region

Body region consisting of the upper and lower limbs.

Mediastinum

Region in the thoracic cavity separating the left and right pleural cavities, containing the heart, blood vessels, esophagus, trachea, and thymus.

Greater Omentum

An abdominal membrane that hangs like an apron from the stomach and transverse colon.

Abduction

Movement of a body part away from the midline.

Adduction

Movement of a body part toward the midline.

Phospholipids

Molecules that make up $75\%$ of plasma membrane lipids, arranged in a bilayer with hydrophilic heads facing water and hydrophobic tails facing the center.

Glycocalyx

A unique fuzzy carbohydrate coating on the external surface of the plasma membrane that acts like a cell's identification tag.

Transmembrane Proteins

Proteins that pass entirely through the lipid bilayer, having hydrophilic regions in contact with fluid and hydrophobic regions inside the membrane.

Filtration

Passive transport process where particles are driven through a selectively permeable membrane by hydrostatic pressure.

Simple Diffusion

Net movement of particles down their concentration gradient from an area of high concentration to an area of low concentration due to constant molecular motion.

Osmosis

Net flow of water through a selectively permeable membrane from a side with higher water concentration to a side with lower water concentration.

Aquaporins

Channel proteins in the plasma membrane specialized for the passage of water.

Hypotonic Solution

A solution with a lower solute concentration than the cytoplasm, causing water to enter the cell so that it swells and may lyse.

Hypertonic Solution

A solution with a higher solute concentration than the cytoplasm, causing water to leave the cell and leading to crenation.

Symport

A carrier protein mechanism that transports two or more solutes simultaneously in the same direction across the membrane.

Antiport

A carrier protein mechanism that transports two or more solutes in opposite directions across the membrane.

Sodium-Potassium Pump

An active transport antiport carrier that consumes one ATP to pump $3\,\text{Na}^+$ out of the cell and $2\,\text{K}^+$ into the cell.

Phagocytosis

A form of endocytosis ("cell eating") where a cell surrounds foreign particles with pseudopods and engulfs them into a vesicle.

Pinocytosis

A form of endocytosis ("cell drinking") in which the plasma membrane dimples to take in droplets of extracellular fluid.

Transcytosis

The process of capturing material on one side of a cell by endocytosis and releasing it on the opposite side by exocytosis.

Nucleus

The largest organelle ($5\,\mu\text{m}$ in diameter) that acts as the genetic control center of the cell and shelters DNA.

Rough Endoplasmic Reticulum

An extensive network of parallel flattened sacs covered with ribosomes that synthesizes proteins and phospholipids.

Smooth Endoplasmic Reticulum

A branching network of tubules without ribosomes that synthesizes steroids and lipids, detoxifies drugs and alcohol, and stores calcium.

Golgi Complex

A system of cisternae that synthesizes carbohydrates and modifies, sorts, and packages newly synthesized proteins into vesicles.

Lysosomes

Membrane-bound packages of hydrolytic enzymes responsible for intracellular digestion, autophagy, and autolysis.

Peroxisomes

Organelles containing enzymes that use molecular oxygen to oxidize organic molecules, producing and breaking down hydrogen peroxide ($\text{H}_2\text{O}_2$).

Mitochondria

Double-membraned organelles specialized for ATP synthesis, containing internal folds called cristae and their own circular mtDNA.

Axoneme

The structural core of cilia and flagella consisting of a $9+2$ array of microtubules that produces movement via dynein arms.

Cystic Fibrosis

A hereditary disease in which chloride pumps fail to install in the membrane, leading to a lack of surface saline layer and thick, blocking mucus.

Centrioles

Short cylindrical assemblies composed of nine triplets of microtubules that organize spindle fibers during cell division.

Microtubules

Hollow cylinders ($25\,\text{nm}$ in diameter) made of $13$ parallel protofilaments of tubulin that maintain cell shape and direct organelle movement.

Inclusions

Unenclosed structures in the cytoplasm, including stored cellular products (glycogen, fat droplets) or foreign matter (debris, pathogens).

Mitosis

Process of cell division that produces two genetically identical body (somatic) cells from a single parent cell.