BIO 208L Exam 1 Review: Microscope, Cells, and Mitosis

Vocabulary flashcards covering microscope concepts, cell organelle structure and function, the cell cycle, and stages of mitosis.

Parfocal

A property of a microscope where an image remains approximately in focus when switching from one objective lens to another.

Field of View

The visible circle of light and specimen area observed through the microscope eyepieces at a specific magnification.

Depth of Field

The vertical thickness or depth of a specimen that remains in sharp focus at one focal setting.

Working Distance

The distance between the bottom tip of the objective lens and the top surface of the specimen slide.

Total Magnification

Calculated by multiplying the magnification power of the ocular lens by the magnification power of the objective lens ($\text{Total Magnification} = \text{Ocular Lens} \times \text{Objective Lens}$).

Compound Light Microscope Parts

Includes ocular lenses, eyepiece, nosepiece, objective lenses, stage, stage clips, condenser, iris diaphragm, lamp, power switch, light adjustment dial, coarse adjustment knob, fine adjustment knob, mechanical stage adjustment knob, arm, and base.

Inverted Microscope Image

The optical phenomenon where a compound microscope turns the specimen image upside down and laterally inverted (e.g., the letter 'e').

Depth of Field Demonstration

An exercise using overlapping colored threads to observe how only one depth plane comes into focus at a time under higher magnification.

Human Cheek Epithelial Cells

Flat squamoid animal cells viewed under microscope magnification showing the outer plasma membrane, cytoplasm, and central stained nucleus.

Plasma Membrane

A double layer of phospholipids with embedded cholesterol and proteins; serves as an external cell barrier, contains transmembrane receptors, transport proteins, and maintains resting potential.

Cytoplasm

Cellular region between the nuclear and plasma membranes; consists of fluid cytosol containing dissolved solutes, organelles, and inclusions.

Mitochondria

Rodlike double-membrane structures with inner membrane folds called cristae; site of ATP synthesis and powerhouse of the cell.

Ribosomes

Dense particles consisting of two subunits composed of ribosomal RNA and protein; function as the sites of protein synthesis.

Rough Endoplasmic Reticulum

Membranous system enclosing cisterns and studded externally with ribosomes; attaches sugar groups to proteins, packages proteins in vesicles, and synthesizes phospholipids.

Smooth Endoplasmic Reticulum

Membranous system of sacs and tubules free of ribosomes; site of lipid and steroid (cholesterol) synthesis, lipid metabolism, drug detoxification, and $\text{Ca}^{2+}$ storage.

Golgi Apparatus

A stack of flattened membranes and associated vesicles close to the nucleus; packages, modifies, and segregates proteins for secretion, inclusion in lysosomes, or incorporation into plasma membrane.

Peroxisomes

Membranous sacs containing catalase and oxidase enzymes that detoxify toxic substances; catalase breaks down hydrogen peroxide.

Lysosomes

Membranous sacs containing acid hydrolases that serve as sites of intracellular digestion.

Microtubules

Cylindrical structures made of tubulin proteins that support the cell, give it shape, participate in cellular movements, and form centrioles, cilia, and flagella.

Intermediate Filaments

Protein fibers of varying composition that serve as stable cytoskeletal elements to resist mechanical forces acting on the cell.

Microfilaments

Fine filaments composed of the protein actin involved in muscle contraction, intracellular movement, and helping form the cell's cytoskeleton.

Centrioles

Paired cylindrical bodies, each composed of nine triplets of microtubules; organize microtubule network as part of centrosome and form spindle and asters during mitosis.

Inclusions

Varied cytoplasmic structures including stored nutrients such as lipid droplets, glycogen granules, protein crystals, and pigment granules.

Cilia

Short cell-surface projections containing nine pairs of microtubules surrounding a central pair; coordinated movement creates a unidirectional current to propel substances.

Flagellum

A long cell extension (only example in humans is the sperm tail) that functions to propel the cell.

Microvilli

Tubular extensions of the plasma membrane containing a bundle of actin filaments that increase surface area for absorption.

Nucleus

Largest organelle, surrounded by nuclear envelope and containing nucleoplasm, nucleoli, and chromatin; serves as control center responsible for genetic information and protein synthesis instructions.

Nuclear Envelope

Double-membrane structure pierced by nuclear pores with outer membrane continuous with ER; separates nucleoplasm from cytoplasm and regulates passage of substances.

Nucleolus

Dense spherical non-membrane-bounded bodies in the nucleus composed of ribosomal RNA and proteins; site of ribosome subunit manufacture.

Chromatin

Granular, threadlike material composed of DNA and histone proteins; DNA constitutes the genes.

Cell Organelles Model

A 3D cell model illustrating major organelles including nucleus, nucleolus, chromatin, ER, Golgi, centrioles, and mitochondria.

The Cell Cycle

The life cycle of a cell consisting of Interphase ($\text{G}_1$, $\text{S}$, $\text{G}_2$) and Mitotic phase ($\text{M}$), which includes Mitosis and Cytokinesis.

Interphase

The phase of the cell cycle during which the cell grows and prepares for division, composed of $\text{G}_1$ (growth), $\text{S}$ (growth and DNA synthesis), and $\text{G}_2$ (growth and final division preparation).

Prophase

First phase of mitosis where chromatin condenses into distinct chromosomes and the nuclear membrane disintegrates.

Metaphase

Second phase of mitosis where spindle fibers attach to centromeres and chromosomes align along the metaphase plate.

Anaphase

Third phase of mitosis where sister chromatids, each now called a chromosome, separate and move to opposite poles.

Telophase

Fourth phase of mitosis where chromosomes arrive at each pole, new nuclear membranes form, and cytoplasmic division begins.

Cytokinesis

Division of the cytoplasm, resulting in two complete daughter cells with identical chromosomes to the original nucleus.

Overview of Mitosis

Diagram showing nuclear division through Prophase, Metaphase, Anaphase, Telophase, and completion of daughter cells.

Whitefish Blastula Mitosis

Microscopic slide images of animal cell division in whitefish blastula illustrating Interphase, Prophase, Metaphase, Anaphase, Telophase, and Cytokinesis.