Bio 1st Quarter: Cell Biology and Theory

Vocabulary flashcards covering the history of cell discovery, cell theory, cell structures and organelles, membrane transport, and the cell cycle as described in the lecture notes.

Lens

A curved piece of glass or another material that makes an object look bigger, historically named after its shape which resembles lentil beans.

Microscope

A tool that uses lenses to make very small objects look much bigger to reveal details invisible to the naked eye.

Zacharias Janssen

A scientist commonly credited with making one of the earliest compound microscopes around $1590$ by placing multiple lenses in a tube.

Robert Hooke

A scientist who observed cork under a microscope in $1665$ and named the tiny box-like spaces 'cells' because they looked like small rooms.

Cellula

A Latin word meaning 'small room' or 'compartment' which Robert Hooke used as the basis for naming cells.

Micrographia

A book authored by Robert Hooke showcasing his observations of tiny objects using a microscope.

Antonie van Leeuwenhoek

A scientist who created powerful microscopes and became one of the first people to observe living microorganisms like bacteria and protists.

Animalcules

The term used by Leeuwenhoek to describe tiny living organisms because they resembled small animals.

Cell Theory

The foundation of biology stating all living things are made of cells, cells perform basic life functions, and new cells come from existing cells.

Matthias Schleiden

A scientist who studied plants and concluded that they are entirely made of cells.

Theodor Schwann

A scientist who studied animals and concluded that they are entirely made of cells.

Rudolf Virchow

A scientist who explained that new cells are produced only from cells that already exist.

Omnis cellula e cellula

A Latin phrase meaning 'every cell comes from another cell,' illustrating the concept of cell division.

Three Main Ideas of Cell Theory

($1$) All living things are made of cells; ($2$) The cell is the basic unit of life; ($3$) All cells come from preexisting cells.

Divine Theory

The belief that life was created by a divine or supernatural power.

Panspermia

The idea that life or its essential ingredients may have originated in outer space and were carried to Earth by asteroids, comets, or meteorites.

Spontaneous Generation

The obsolete belief that living things could appear directly from nonliving matter, such as maggots arising from rotting meat.

Francisco Redi

A scientist whose meat experiment proved that maggots come from flies, challenging the idea of spontaneous generation.

John Needham

A scientist who argued for spontaneous generation after observing microorganisms appearing in boiled and sealed broth.

Lazzaro Spallanzani

A scientist who refuted Needham's findings by boiling broth longer and sealing it properly, showing microorganisms come from outside contamination.

Louis Pasteur

The scientist who used a swan-neck flask experiment to prove that microorganisms come from the environment, not from the broth itself.

Prokaryotic Cell

A simple cell lacking a true nucleus, where DNA is stored in an area called the nucleoid; examples include bacteria.

Eukaryotic Cell

A complex cell containing a true nucleus that houses DNA; found in animals, plants, fungi, and protists.

Nucleus

The cell's control room that stores DNA and manages the cell's various functions and activities.

Nucleoid

The membrane-less region in a prokaryotic cell where the DNA is located.

Peptidoglycan

A strong material found in the cell walls of bacteria that acts as protective armor.

Cellulose

A strong material comprising plant cell walls that provides structural support and shape.

Binary Fission

A form of reproduction in bacteria where the cell copies its DNA and splits into two identical cells.

Cell

The smallest basic unit capable of carrying out all functions required for life.

Cell Membrane

The cell's security guard or gate that surrounds the cell and regulates what enters and exits to maintain stability.

Cytoplasm

The jelly-like material filling the cell interior where organelles are suspended and chemical reactions occur.

DNA

The cell's instruction manual containing genetic information for building proteins and performing functions.

Nucleolus

A small region located inside the nucleus responsible for the production of ribosome parts.

Ribosomes

Protein-making machines that read RNA instructions to build proteins for growth, repair, and enzymes.

Rough Endoplasmic Reticulum (Rough ER)

A factory for protein making and processing studded with ribosomes on its surface.

Smooth Endoplasmic Reticulum (Smooth ER)

A lipid-making factory that produces fats, phospholipids, and steroids, and aids in detoxification.

Golgi Apparatus

A packing and delivery center that modifies materials, packs them into vesicles, and sends them to their destinations.

Vesicles

Tiny delivery packages used to transport proteins, lipids, and other materials throughout the cell or to the membrane.

Lysosomes

The cell's recycling and garbage disposal system that uses enzymes to break down waste and old cell parts.

Peroxisomes

The cell's clean-up and detox center that breaks down fatty acids and protects the cell from dangerous chemicals.

Mitochondria

The cell's power plants that convert food molecules into $ATP$ through cellular respiration.

ATP

The cell's usable energy currency required for movement, transport, and building molecules.

Cytoskeleton

The cell's internal skeleton that provides shape, organizes organelles, and facilitates intracellular movement.

Centrioles

Structures that organize microtubules to help separate chromosomes during cell division.

Cilia

Short, hair-like structures used for cell movement or to move substances across the cell's external surface.

Flagellum

A long, whip-like structure used by cells, such as sperm, to swim through liquid.

Vacuole

A storage container for water, food, and waste; plant cells typically feature a very large central vacuole.

Cell Wall

A rigid outer layer in plants, fungi, and bacteria that provides support, protection, and specific shape.

Chloroplast

A plant cell organelle that captures sunlight to produce food via photosynthesis.

Chlorophyll

The green pigment found in chloroplasts that absorbs light energy.

Phospholipid

The main component of the cell membrane, consisting of a hydrophilic head and hydrophobic tails.

Hydrophilic

A term meaning 'water-loving,' describing the head of a phospholipid.

Hydrophobic

A term meaning 'water-fearing,' describing the tails of a phospholipid.

Phospholipid Bilayer

The double-layered structure of the cell membrane where tails face inward and heads face the watery environment.

Fluid Mosaic Model

The concept that the cell membrane is a flexible, moving fluid composed of many different parts like a mosaic.

Cholesterol

A molecule in the membrane that regulates fluidity, preventing it from becoming too stiff or too fluid.

Integral Protein

A protein built into the membrane that can span its entire width to act as a door or tunnel.

Peripheral Protein

A protein that is attached to the surface of the cell membrane.

Glycoprotein

A protein with an attached carbohydrate that functions as a cell identification tag for recognition.

Glycolipid

A lipid with an attached carbohydrate used for membrane stability and cell recognition.

Diffusion

The natural movement of molecules from an area of high concentration to an area of low concentration.

Passive Transport

The movement of substances across the membrane from high to low concentration without the expenditure of energy.

Simple Diffusion

The direct movement of small molecules through the membrane without the aid of proteins or $ATP$.

Facilitated Diffusion

The movement of molecules from high to low concentration via a specific membrane protein.

Channel Protein

A protein that creates a tunnel through the membrane for specific substances to pass.

Carrier Protein

A protein that binds with a substance and changes shape to transport it across the membrane.

Aquaporin

A specialized channel protein that facilitates the rapid movement of water across the cell membrane.

Active Transport

The movement of molecules from low to high concentration which requires energy in the form of $ATP$.

Endocytosis

The process by which a cell brings external materials inside by engulfing them with the cell membrane to form a vesicle.

Phagocytosis

Often called 'cell eating,' it is the process of taking in large solid objects like bacteria.

Pinocytosis

Often called 'cell drinking,' it is the process of taking in droplets of fluid.

Receptor-Mediated Endocytosis

A process where reaching specific receptors triggers the cell to bring recognized substances inside.

Exocytosis

The process of releasing materials outside the cell when a vesicle merges with the cell membrane.

Osmosis

The movement of water across a selectively permeable membrane.

Isotonic

A state where the solute concentration outside the cell equals the concentration inside, resulting in no net size change.

Hypotonic

A solution with a lower solute concentration than the cell, causing water to enter and make the cell swell or burst.

Cytolysis

The bursting of an animal cell due to the intake of excess water in a hypotonic environment.

Hypertonic

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

Crenation

The shrinking of an animal cell as water leaves it in a hypertonic environment.

Cell Cycle

The sequence of growth, DNA replication, and division that a cell undergoes.

Interphase

The phase of the cell cycle where the cell grows, performs normal functions, and prepares for division; includes $G1$, $S$, and $G2$ phases.

S Phase

The specific part of interphase where the cell replicates its DNA.

M Phase

The part of the cell cycle where the cell undergoes mitosis and cytokinesis to create new cells.

Mitosis

A division process resulting in two genetically similar daughter cells, used for growth and repair.

Prophase

The first stage of mitosis where chromosomes become visible, the nucleus breaks down, and the spindle forms.

Metaphase

The stage of mitosis where chromosomes align in a straight line in the middle of the cell.

Anaphase

The stage of mitosis where sister chromatids are pulled apart toward opposite ends of the cell.

Telophase

The final stage of mitosis where two new nuclei form around the separated chromosomes.

Cytokinesis

The process following mitosis where the cytoplasm splits to form two separate daughter cells.

Cell-Cycle Checkpoint

A safety mechanism that monitors if a cell is ready to proceed to the next stage of division.

P53

A protein that monitors DNA health and can stop division or trigger apoptosis if damage is detected.

Apoptosis

Programmed cell death that occurs when a cell is significantly damaged or no longer needed.