Biology 1 Reviewer: Cell Theory, Cell Structures, Cell Cycle, Transport, and Metabolism

Comprehensive set of vocabulary flashcards covering key terms, historical scientists, organelle functions, microscopic concepts, cell cycle phases, membrane transport mechanisms, and cellular metabolism from the lecture notes.

Theory of Spontaneous Generation (Abiogenesis)

A theory suggesting that organisms can arise from non-living things under certain environmental conditions.

Francesco Redi

Italian scientist who designed an experiment in 1688 with open, cork-sealed, and gauze-covered containers of meat to disprove spontaneous generation by showing maggots come from fly eggs.

John Needham

An English naturalist who challenged Redi in 1745 by boiling broth in a sealed flask; he claimed microorganisms grew spontaneously because he did not heat the broth long enough.

Lazzaro Spallanzani

Scientist who disputed Needham's results by showing that sealed boiled broth only developed microbial growth after being opened and exposed to air, proving air is a factor for microbial growth.

Louis Pasteur

French chemist who ended the spontaneous generation dispute using S-shaped swan neck flasks and was awarded the Alhumbert Prize by the Paris Academy of Sciences in 1862.

Alhumbert Prize

A prestigious prize awarded by the Paris Academy of Sciences in 1862 to Louis Pasteur for disproving spontaneous generation.

Zacharias Janssen

A Dutch inventor and spectacles maker believed to be the first to invent a compound microscope in 1590.

Robert Brown

An English botanist who noted that every plant cell contained a circular structure, which he named the Nucleus (Latin for 'kernel').

Karl Nägeli

A Swiss botanist who expanded cell theory through his observations on the concept of cell division.

Robert Hooke

Scientist who observed thin slices of cork in 1668 under 30x magnification and called the boxlike compartments 'Cells' from the Latin word 'Cellula'.

Cellula

Latin word meaning 'Little rooms', which served as the origin for the word 'Cell'.

Antonie van Leeuwenhoek

Dutch scientist and master microscope maker who observed miniscule organisms ('animacules') including blood cells and sperm cells at up to 300x magnification.

Animacules

The name given by Antonie van Leeuwenhoek to miniscule organisms like bacteria and protozoa due to their movement.

Matthias Jakob Schleiden

German botanist who published a paper in 1838 suggesting that 'all plant tissues are compounds of cells.'

Theodor Schwann

German zoologist who stated that 'all animal tissues are composed of cells' and discovered Schwann cells around peripheral nerve fibers.

Schwann Cells

Cells discovered by Theodor Schwann that form the myelin sheath around peripheral nerve fibers.

Rudolf Virchow

German scientist who generalized the phrase 'omnis cellula e cellula' in 1855, establishing that all cells arise from the division of preexisting cells.

Omnis cellula e cellula

A Latin phrase meaning 'all cells arise from the division of other preexisting cells'.

Prokaryotic Cells

Smaller cells that lack a true membrane-bound nucleus and membrane-bound organelles, typically found in bacteria and archaea.

Eukaryotic Cells

Organisms containing a membrane-bound nucleus and various organelles, found in animals, plants, fungi, and protists.

Cell Membrane (Plasmalemma)

A semi-permeable boundary composed of lipids and proteins that encloses the cell and regulates entry and exit of materials.

Cell Wall

An outer layer present in plants, fungi, and bacteria made of middle lamina, primary, and secondary cell walls that provides structure, protection, and filtering.

Centriole

Tubular structures in eukaryotic cells composed of tubulin that organize spindle fibers during cell division and assist cilia and flagella formation.

Cilia and Flagella

Tiny hair-like projections made of microtubules covered by plasma membrane used primarily for movement and sensing.

Chloroplast

A double-membraned plastid organelle containing chlorophyll that serves as the primary site for photosynthesis in plants and algae.

Cytoplasm

Everything present inside the cell except the nucleus, serving as the site for enzymatic reactions like cellular respiration and translation.

Cytoskeleton

Fibrous structures present in the cytosol that give shape to the cell and support intracellular and extracellular transport.

Rough Endoplasmic Reticulum (Rough ER)

A network of tubules connected to the nuclear membrane studded with ribosomes, directly involved in protein synthesis.

Smooth Endoplasmic Reticulum (Smooth ER)

A network of tubules lacking ribosomes that functions in lipid synthesis (such as cholesterol and steroids).

Endosomes

Membrane-bound compartments originating from the Golgi network involved in sorting and delivering internalized materials.

Golgi Apparatus

Eukaryotic organelle responsible for packaging macromolecules into vesicles for transport to their site of action.

Lysosomes

Membrane-bound organelles in animal cells containing hydrolytic enzymes, known as 'suicide bags' for their ability to undergo self-destruction.

Microvilli

Tiny finger-like projections on the cell surface packed with enzymes that increase surface area to enhance absorption and secretion.

Mitochondria

The 'powerhouse' of the cell whose primary function is to synthesize energy in the form of Adenosine Triphosphate (ATP).

Adenosine Triphosphate (ATP)

The major energy currency of the cell that powers most cellular energy-consuming activities.

Nucleus

The 'brain of the cell' that controls organelle activities and stores/transfers genetic material in the form of DNA or RNA.

Peroxisomes

Oxidative membrane-bound organelles found in the cytoplasm of all eukaryotes used for cell detoxification.

Ribosomes

Structures composed of equal parts RNA and proteins required for protein synthesis, found freely or attached to the ER.

Vacuole

Storage organelle for nutrients and waste products; in plant cells, it exists as one large central vacuole performing digestive functions.

Scanning Objective

The microscope objective lens offering the lowest magnification (4x), used for locating the specimen.

Low Power Objective (LPO)

The microscope objective lens providing medium magnification (10x), used for general viewing.

High Power Objective (HPO)

The microscope objective lens providing high magnification (40x), used for detailed observations.

Oil Immersion Objective (OIO)

The microscope objective lens providing very high magnification (100x), requiring oil for clarity and resolution.

Transmission Electron Microscope (TEM)

A microscope that passes an electron beam through ultra-thin specimens (less than 100 nanometers) to observe 2-D internal structures.

Scanning Electron Microscope (SEM)

A microscope that directs a focused beam of electrons across a specimen's surface to produce detailed 3D images of topography and morphology.

Interphase

The longest resting phase of the cell cycle where the cell is metabolically active, growing, and replicating its DNA.

G1 Phase

Sub-phase of interphase where the cell grows exponentially and synthesizes proteins needed for DNA replication.

S Phase

The longest sub-phase of interphase (10-12 hours) where genetic material and centrosomes are duplicated.

G2 Phase

Sub-phase of interphase where energy storage is renewed, organelles duplicate, and cytoskeleton disassembles for the mitotic spindle.

Mitosis

Type of cell division occurring in somatic (body) cells resulting in identical daughter cells.

Chromatin

Loose, uncoiled form of DNA appearing as a tangled mass of thin threads.

Chromosomes

Highly coiled and condensed structures of DNA.

Prophase

First stage of mitosis where chromatin condenses into sister chromatids, the nucleolus disappears, and the spindle forms.

Metaphase

Mitosis phase where chromosomes align at the imaginary equatorial plane called the metaphase plate.

Anaphase

Mitosis phase where sister chromatids separate at the centromere and move away toward opposite spindle poles.

Telophase

Mitosis phase where spindle fibers disappear, daughter nuclei form at opposite poles, and nuclear envelopes reappear.

Cytokinesis

The division of the cytoplasm, marked by the formation of a cleavage furrow in animal cells.

G0 Phase

Resting state outside the main cell cycle where differentiated cells (such as neurons) remain viable and active but do not divide.

Meiosis

Cell division occurring in sex cells where a diploid parent cell divides twice to produce four haploid daughter cells.

Homologous Chromosomes

Chromosome pairs (one from each parent) sharing the same length, centromere position, and gene locations.

Autosomes

Any chromosome that is not a sex chromosome, totaling 22 pairs in humans.

Sex Chromosome

The 23rd pair of chromosomes determining the gender of an individual (XY = male, XX = female).

Synapsis

The pairing of homologous chromosomes during Prophase I of meiosis.

Crossing Over

The swapping of genetic material between non-sister chromatids during Prophase I at points called chiasmata.

Chiasmata

The exact points where non-sister chromatids meet and exchange genetic material during crossing over.

Kinetochores

Protein complexes located outside centromeres that bind to polar spindle fibers during cell division.

Interkinesis

A short pause or resting phase between Meiosis I and Meiosis II.

Amphipathic

Having both hydrophilic (water-loving) and hydrophobic (water-hating) properties, such as phospholipid molecules.

Carrier Protein

Membrane protein used in active transport to move substances against their concentration gradient using chemical energy (ATP).

Channel Protein

Membrane protein used in passive transport allowing specific molecules to cross the cell membrane quickly.

Osmosis

The diffusion of water molecules across a semi-permeable membrane from an area of higher concentration to lower concentration.

Tonicity

The capability of an extracellular solution to modify cell volume by causing it to gain or lose water.

Isotonicity

State where solute concentration is equal inside and outside the cell, resulting in equal rates of water diffusion and no volume change.

Hypertonicity

State where solute concentration is higher outside the cell, causing water to leave the cell and make it shrink or shrivel.

Hypotonicity

State where solute concentration is lower outside the cell, causing rapid water entry leading to cell swelling and lysis.

Passive Transport

Movement of substances across a cell membrane along the concentration gradient (high to low) without energy expenditure.

Facilitated Diffusion

Passive transport process where large molecules like glucose require specific carrier proteins to cross the cell membrane.

Active Transport

Energy-requiring movement of substances across a cell membrane against their concentration gradient (low to high).

Sodium-Potassium Pump

An active transport mechanism that uses ATP energy to exchange sodium ions for potassium ions across the cell membrane.

Phagocytosis

Type of endocytosis known as 'cell eating' where the cell engulfs solid particles to be digested by lysosomes.

Pinocytosis

Type of endocytosis known as 'cell drinking' where the cell internalizes extracellular fluid and dissolved solutes.

Receptor-Mediated Endocytosis

Targeted endocytosis where cell surface receptor proteins capture specific target molecules before membrane invagination.

Exocytosis

Process where vesicles transport macromolecules to the plasma membrane to expel waste or secrete hormones out of the cell.

Anabolism

Metabolic processes that require energy to build larger molecules from smaller units.

Catabolism

Metabolic processes that break down complex molecules into simpler ones, releasing energy.

Photosynthesis

An anabolic process taking place in chloroplasts that converts solar energy into chemical energy stored in glucose.

Stroma

The gel-like fluid enclosed by the inner membrane of the chloroplast surrounding the thylakoids.

Thylakoids

Disc-like membrane structures inside the chloroplast containing chlorophyll; stacked into structures called grana.

Chlorophyll a

The primary photosynthetic pigment present in all photosynthetic organisms that absorbs violet-blue and red light.

Chlorophyll b

An accessory photosynthetic pigment found in plants, green algae, and cyanobacteria that absorbs blue and yellow light.

Carotenoids

Accessory pigments absorbing violet and blue-green light, responsible for yellow, red, and orange colors with photoprotective roles.