Unit 1 Biology Test 1 Revision - Principles of Biology and Cell Structure

A comprehensive set of vocabulary flashcards covering basic principles of biology, cell structures (organelles), membrane composition, and mechanisms of cellular transport based on the lecture notes.

Cell theory

The set of principles stating that all organisms are made up of cells, all cells come from pre-existing cells, and the cell is the smallest living organisational units.

Living organisms

Entities that eat, respond, reproduce, and grow.

Inorganic molecules

Non-carbon based molecules mentioned as Water ($H_2O$), Oxygen ($O_2$), $CO_2$, $N_2$, and Minerals.

Organic molecules

Molecules such as Carbohydrates (e.g. glucose, starch), Lipids (fats), Proteins (e.g. enzymes), Nucleic Acids (e.g. DNA), and Vitamins.

Prokaryotes

Primitive cells, specifically Monera, which have no obvious structural organization and a circular DNA chromosome.

Eukaryotes

Cells found in kingdoms Protista, Fungi, Animalia, and Plantae that contain organelles and DNA in linear chromosomes within a nucleus.

Cell wall

A structure that gives plant cells support and stops the cell from bursting when it is turgid.

Cytoplasm

All of the interior of the cell comprised of the ions, cytosol, organelles, and other internal components.

Nucleus

Organelle containing all the DNA and the information required to tell the cell what to do.

Nuclear envelope

The surrounding membrane, also known as the nuclear membrane, that holds together the nucleus and keeps genetic material and the nucleolus intact.

Nucleolus

A round granular structure within the nucleus composed of protein and RNA, which does not have a membrane.

Cytoskeleton

An internal framework of a cell composed of protein filaments and microtubules that controls cell shape and movement.

Centrioles

Structures that produce spindle fibers for use in cell division.

Mitochondrion

The organelle where cellular respiration takes place.

Endoplasmic reticulum (ER)

An organelle involved in protein synthesis and the production, synthesis, and transport of proteins.

Rough endoplasmic reticulum (RER)

Endoplasmic reticulum that has ribosomes attached to it.

Smooth endoplasmic reticulum (SER)

Endoplasmic reticulum with no ribosomes attached; it is involved in the synthesis of molecules other than proteins.

Endomembrane system

The group of organelles containing the Golgi apparatus, nuclear membrane, ER, and cell membrane.

Ribosomes

The site of protein synthesis where RNA is translated into proteins.

Golgi bodies

Organelles that modify proteins and pack them into vesicles for release from the cell.

Lysosomes

Organelles containing powerful digestive enzymes used to break down debris and foreign material.

Cilia and flagella

Tail-like or hair-like structures on the cell that help it move around.

Vacuoles

Fluid-filled organelles containing water and sap that provide structural support to plant cells.

Chloroplasts

The site of photosynthesis which contains the light-trapping pigment chlorophyll.

Extracellular fluid

The fluid surrounding all cells; in multicellular organisms, this fluid constitutes the regulated internal environment.

Phospholipid bilayer

The structure of cell membranes composed of molecules with a hydrophilic and a hydrophobic end.

Surface area to volume ratio

A ratio where higher values indicate more surface contact with the environment; organisms adapt large ratio organs like lungs and leaves.

Diffusion (Passive Transport)

The passive movement of molecules and particles along a concentration gradient from a region of high concentration to low concentration.

Facilitated Diffusion

The movement of a substance through the cell membrane via a carrier molecule, carrier protein, or protein channel.

Concentration Gradient

The difference in concentration between two regions.

Active Transport

An active mechanism requiring energy expenditure to move molecules from low concentration to high concentration across a concentration gradient.

Exocytosis

The secretion of molecules from within a cell to the outside by packing them into vesicles.

Endocytosis

The intake of molecules from outside a cell to the inside by packing them into vesicles found in the plasma membrane.

Phagocytosis

The process of taking solids into the cell by endocytosis.

Pinocytosis

The process of taking liquids into the cell by endocytosis.

Osmosis

The movement of molecules from a place of high water concentration to a place of low water concentration through a semi-permeable membrane.

Plasmolysis

The shrinking of the cytoplasm as a result of water loss from the cell due to osmosis.

Flaccid

Describing a cell that has lost water, causing the vacuole to shrink and the cell to lose its shape.

Turgid

Describing a cell that is full of water (swollen) and cannot gain anymore without the risk of popping.

Isotonic

A condition where the solution around a cell has the same concentration as the solution inside the cell, resulting in no net movement of water.

Hypotonic

A condition where the solution around a cell is more dilute than the inside, causing water to move into the cell.

Hypertonic

A condition where the solution around a cell is more concentrate than the inside, causing water to move out of the cell.

Solute

A substance, such as molecules or particles, dissolved in another substance.

Solvent

A substance, such as water or liquid, in which other substances can be dissolved.