BIOL21300 A&P-I Laboratory 3: Cell Structure & Organelles

This set of vocabulary flashcards covers cell structures, organelles, and the phases of the cell cycle and mitosis based on the BIOL21300 A&P-I Lab 3 transcript.

Human sperm head diameter

$$2\,\mu m$$

Erythrocyte diameter

Between $7-8\,m$ ($7.5\,m$)

Human oocyte diameter

$$120\,\mu m$$

Simple squamous epithelium function

Forms a barrier

Smooth muscle cells function

Involuntary contraction

Platelets function

Blood clotting

Plasma membrane

Provides a selectively permeable barrier between the intracellular and extracellular environments of the cell

Cytoplasm

Includes cellular organelles and cytosol (intracellular fluid)

Nucleus

The most noticeable feature of a cell that contains the genetic material (DNA)

Nucleolus

A small, dark, circular structure within the nucleus that synthesizes rRNA and assembles ribosomes

Chromatin

Genetic material within the nucleus consisting of uncoiled chromosomes and associated proteins

Cytoskeleton

Provides the main structural support for the cell and is composed of microtubules, intermediate filaments, and microfilaments

Microfilaments

Helical polymers composed of a filamentous protein called actin

Microtubules

Hollow cylinders of globular protein called tubulin

Rough Endoplasmic Reticulum (RER)

Extensive membrane network with ribosomes involved in protein synthesis destined for the cell membrane, lysosomes, or secretion

Smooth Endoplasmic Reticulum (SER)

Extensive membrane network without ribosomes involved in lipid and carbohydrate synthesis and detoxification of drugs and poisons

Golgi Apparatus

Stack of flattened membranes (cisternae) that modify, package, and sort proteins for delivery

Mitochondria

Double-membrane, oblong organelles known as the "powerhouse" of the cell; the site of aerobic cellular respiration used to produce ATP

Cristae

The arrangements of the inner mitochondrial membrane designed to increase surface area for energy production

Matrix

The space within the inner membrane of the mitochondrion

Lysosomes

Membrane-enclosed sacs containing digestive enzymes formed by the Golgi; they break down intracellular debris or unneeded substances

Peroxisomes

Membrane-enclosed sacs containing catalase and oxidative enzymes that breakdown lipids and toxic substances

Ribosomes

Sites of protein synthesis made of protein and ribonucleic acid; can be bound (attached to ER) or free (suspended in cytosol)

Centrosome

An area next to the nucleus containing a pair of perpendicularly oriented cylindrical centrioles used to organize spindle microtubules during cell division

Microvilli

Plasma membrane modifications that increase surface area for absorption, commonly found in the GI tract

Cilia

Plasma membrane modifications that move mucus, found in respiratory airways

Flagellum

A plasma membrane modification that propels/moves the sperm cell

Diploid ($2n$)

Having two copies for each chromosome; human somatic cells have 46 chromosomes ($2 \times 23$)

Haploid ($1n$)

The state of sex cells (sperm or oocytes) having 23 chromosomes

Cell Cycle

A series of ordered events including Interphase and the Mitotic (M) phase as a cell grows and divides

S phase

The synthesis phase of interphase where DNA (chromosomes) and centrioles are duplicated

Prophase

First stage of mitosis where chromatin supercoils into chromosomes, the nucleolus breaks down, and spindle fibers grow from centrioles

Metaphase

Second stage of mitosis where chromosomes align on the equatorial plate and spindle fibers attach at the centromere

Anaphase

Third stage of mitosis where spindle fibers move sister chromatids apart toward opposite poles

Telophase

Fourth stage of mitosis where chromosomes arrive at poles and uncoil, new nucleoli and nuclear envelopes form, and the mitotic spindle breaks up

Cytokinesis

The division of the cytoplasm between two newly formed cells, resulting in a cleavage furrow and two daughter cells