Cell Structure and Function

Comprehensive vocabulary flashcards covering cell history, theory, types, organelles, and structures based on the Chapter 4 lecture transcript.

Cellulae

The name given by Robert Hooke to the multitude of tiny pores described as "tiny rooms" observed in slices of cork.

Robert Hooke

The scientist who discovered the cell in 1665 while observing slices of cork under a crude microscope.

Antonie van Leeuwenhoek

Known as the Father of Microbiology, he was the first person to witness a live cell under a microscope in the 1670s.

Cell Theory (Original)

1) All living organisms are made of cells; 2) The cell is the fundamental unit of structure, function and organization of life; 3) All cells come from pre-existing cells.

Rudolph Virchow

The scientist who proposed in 1858 that all cells come from pre-existing cells.

Schleiden and Schwann

The scientists who proposed in 1838 that all living organisms are made of cells and that the cell is the fundamental unit of life.

Modern interpretation of the cell theory

The added concepts that cells contain hereditary material and that cells process energy.

Cell Size Range

Most cells are between $1$ and $100\,\mu\text{m}$ in diameter.

Light Micrograph (LM)

A view of a specimen using light, which can be used to observe either living or dead specimens.

Scanning Electron Micrograph (SEM)

A view of the surface features of a specimen; requires the specimen to be killed and often colorized.

Transmission Electron Micrograph (TEM)

A view of the internal structures of a specimen; requires the specimen to be killed.

Universal Components of All Cells

DNA, cytoplasm, plasma membrane, and ribosomes.

Prokaryotic Cells

Smaller, simpler cells that evolved approximately $3.5$ billion years ago and lack membrane-bound organelles.

Nucleoid

The region in a prokaryotic cell that contains a single circular bacterial chromosome.

Eukaryotic Cells

Larger, more complex cells that evolved approximately $1.8$ billion years ago and contain membrane-bound organelles like the nucleus and ER.

Virus Structure

Consists of a protein coat, nucleic acid (genetic code DNA or RNA), and sometimes an envelope with spikes for attachment.

Plasma (Cell) Membrane

A semi-permeable or selectively permeable membrane composed primarily of phospholipids.

Fluid Mosaic Model

A model of the cell membrane where 'Mosaic' refers to embedded molecules (cholesterol, proteins, glycoproteins, glycolipids) and 'Fluid' means phospholipids are not chemically bonded.

Nucleus

The organelle that protects DNA from the metabolic processes of the cell.

Nuclear envelope

The outer boundary of the nucleus that controls access to the DNA.

Nucleoplasm

The viscous fluid enclosed by the nuclear envelope.

Nucleolus

A dense, irregularly shaped region within the nucleus where ribosomal subunits are produced.

Chromatin

A fiber consisting of a DNA molecule and its associated proteins.

Ribosomes

Organelles responsible for protein synthesis and the formation of peptide bonds between amino acids.

Endomembrane System

A series of interacting organelles (including the ER, Golgi body, and vesicles) between the nucleus and plasma membrane used for manufacturing and distributing cellular products.

Rough ER

A portion of the endoplasmic reticulum with attached ribosomes where proteins are folded into their tertiary structure.

Smooth ER

A portion of the endoplasmic reticulum involved in lipid production, carbohydrate/fatty acid breakdown, detoxification, and muscle contraction.

Golgi Apparatus

A stack of flattened sacs that acts as a molecular warehouse and finishing factory for proteins and lipids from the ER.

Lysosomes

Vesicles containing digestive enzymes that break down cellular wastes and debris.

Contractile Vacuole

Found in protists like Paramecium, it fills with water and then contracts to pump it out of the cell.

Central vacuole

The often largest organelle in a mature plant cell used for storage and maintaining structure.

Mitochondria

The 'Power House' of the cell where cellular respiration occurs to convert the chemical energy of food into ATP.

Chloroplasts

Organelles in plants and some protists that convert light energy into chemical energy through photosynthesis.

Stroma

The fluid contained within the chloroplast.

Cytoskeleton

A network of protein fibers (microtubules, microfilaments, and intermediate filaments) providing structural support and motility.

Extracellular matrix

A complex mixture of polysaccharides and proteins that provides support and organization outside animal cells.

Cuticle

A covering secreted by cells at a body surface, used in plants for protection from insects and water retention.

Homeostasis

The maintenance of a constant internal body temperature and a characteristic of all life.

Domain Eukarya

The domain containing all organisms that are not prokaryotes.