Biol-1115 Lab

Resolution

Ability to see finedetail

Parfocal

Focus remains constant even when magnification or focal length changes

Working distance

Distance from objective lens to slide

Image reversal

Left-right & top-bottom. Specific to light compound microscope.

Advantages of stereoscopic dissecting microscope:

1. Ability to observe objects that are too large/ thick.

2. Ability to observe objects in 3D

3. Image reversal does not occur.

Total magnification

The product of objective & ocular lenses

Field diameter

Number of millimetres seen in whole field of view through ocular lenses.

Stage micrometer

1 cm ruler on glass slide

Scale

Size of drawing relative to true size of organism. Drawing diameter divided by true diameter of organism in mm

True diameter

The field diameter multiplied by the linear fraction in mm

True size

The actual, unmagnified size of organism on slide

Cross section

Cut at right angles to the longitudinal axis of an object

Longitudinal section

Cut parallel to the longitudinal axis of an object

Median section

Cut along the middle of an object

Radial section

Cut made along a radius of a circular object.

Organelles

Mitochondria, chloroplasts, lysosomes, endoplasmic reticulum, Golgi apparatus.

Cytoskeleton

A network of microtubules, microfilaments, & intermediate filaments that extends throughout the cytoplasm & serves a variety of mechanical, transport, & signalling functions.

Mitochondria

Where cellular respiration occur & ATP is generated

Food vacuoles

A membranous sac formed by phagocytosis of microorganism or particles to be used as food by the cell

Cilia

Short appendage containing microtubules. Specialized for locomotion or moving fluid past the cell. Primary cilia are non - motile for sensory & signalling.

Flagella

Long cellular appendage specialized for locomotion

Chloroplasts

Specific to plant cells. Absorbs sunlight & uses it to drive the synthesis of organic compounds from carbon dioxide & water.

Lysosomes

Digestive organelle where macromolecules are hydrolyzed.

Endoplasmic reticulum

Network of membranous sacs & tubes; active in membrane synthesis & other synthetic & metabolic processes

Golgi apparatus

Active in synthesis, modification, sorting, & secretion of cell products from endoplasmic reticulum.

Central vacuole

Specific to mature plant cells. A large membranous sac with diverse roles in growth, storage, & sequestration of toxic substances

Cell wall

Specific to plant cells. A rigid structure surrounding the cell.

Centrioles

Specific to animal cells. A structure in the cytoplasm that functions as a microtubule organizing center & is important during cell division. Has 2 centrioles

Ovum

Mature female egg cell.

Plasma (cell) membrane

Membrane enclosing the cell

Chromosome

Cellular structure consisting of one DNA molecule & associated proteins

Nucleus

Holds genetic material in the form of chromosomes. Made up of chromatin. Contains the nuclear envelope, nucleolus, & chromatin.

Nuclear membrane

Membrane enclosing the nucleus

Nucleolus

A nonmembranous structure involved in production of ribosomes; a nucleus has one or more nucleoli.

Epidermis

Simple plant tissue in non woody plants. Outer most layer of cells in animals.

Prokaryotic cells

Lacks any membrane-bound organelles or a true nucleus. DNA is held in nuclei

Eukaryotic cells

Presence of membrane-bound organelles. DNA held in nucleus.

Plant cells

Has a cell wall, central vacuole, chloroplasts, & plasmodesmata. Only has microfilaments & micro tubules in its cytoskeleton.

Animal cells

Has a lysosome, centrosome, & flagellum. Has microvilli & intermediate filaments a part of its cytoskeleton.

Rough endoplasmic reticulum

Active in protein synthesis, folding, & quality control; covered in ribosomes.

Smooth endoplasmic reticulum

Active in synthesis of lipids, carbohydrates metabolism, & detoxification; free of ribosomes.

Cytoplasm

Content of the cell enclosed by the cell membrane.

Tissue

Group of similar cells performing a common activity

Histology

Study of tissues

Organ

Group of tissues collectively performing a specific function

Organ system

Group of organs performing a major body function

Indeterminate growth

Continues to grow bigger & taller throughout their lives. (Plants)

Determinate growth

Achieves a mature size & stops growing (animals)

Epithelial tissue

Forms the covering & lining of free body surfaces, internal & external. Functions for protection (surface of skin & lining of internal organs), absorption of nutrients (in intestines), secretion (in kidneys, salivary glands, intestines, thyroid gland), lubrication (in areas where mucus is produced), & exchange of materials by diffusion (lungs & blood capillaries)

Basement membrane

Separates epithelium from underlaying tissue

Apical (luminal) surface

Free surface of epithelium which is exposed to air (skin) or fluid (stomach)

Microvilli

Located in lumen to increase surface area

Epithelial tissue function

Barrier against mechanical injury, pathogens, & fluid loss

Epithelial cell shapes:

Squamous: flat, scale-like

Cuboidal: appear square in side view, nucleus in center

Columnar: appear rectangular in side view, nuclear towards base of cell

Simple epithelial

Cells are arranged in one single layer

Stratified epithelial

Cells are arranged in two or more layers.

Simple columnar epithelium function

Absorption of nutrients, secretion of digestive juices, & secretion of mucus by goblet cells.

Villi & crypts

Outward finger-like extensions & inward indentations, respectively → increases surface area of small intestine

Nephrons

Formation of urine

Simple cuboidal epithelial function

Secretion & absorption. Found in kidneys, thyroid gland, sweat glands, & salivary gland.

Simple squamous epithelium function

Allows substances to easily diffuse through cells to be filtered through → thinnest epithelium → found in kidney walls, internal surfaces of ventral body cavities, blood vessels, lymphatic vessels, & heart.

Stratified squamous epithelium (non-keratinized (wet)) function

protection against abrasion & pathogens → oral cavity, pharynx, esophagus, vagina, & anus.

Stratified squamous epithelium (keratinized (dry)) function

Known as epidermis: thick → soles of feet, palms of hands. Thin → found everywhere else.

Pseudostratified ciliates columnar epithelium

Protection, secrete mucus by goblet cells, &move mucus by cilia → the nasal cavity, trachea, & bronchi

Goblet cells

Secrete mucus into the respiratory tree. Usually lack stain & cilia.

Glomeruli

Cluster of capillaries at end of kidney tubules where waste is filtered out of blood

Simple columnar epithelium → small intestine

Simple columnar epithelium → small intestine

Simple columnar epithelium → small intestine

Simple columnar epithelium → small intestine

1. Simple squamous epithelium

2. Simple cuboidal epithelium → kidneys

1. Simple cuboidal epithelium

2. Simple squamous epithelium → kidneys

Simple cuboidal epithelium → kidneys

Simple squamous epithelium → alveoli of lung

Stratified squamous epithelium, non-keratinized → esophagus

Stratified squamous epithelium, keratinized → skin

1. Keratin layer (thin) → ex. Face

2. Stratified squamous epithelium (epidermis) → skin

1. Pseudostratified columnar epithelium, with cilia → trachea

2. Hyaline cartilage

1. Pseudostratified columnar epithelium, with cilia → trachea

2. Connective tissue

Pseudostratified columnar epithelium, with cilia

Connective tissue

Most abundant, support, anchor, & connect.

Extracellular matrix

Fibres & ground substance in connective tissue

Fibroblasts

Most common cell in connective tissue → produces fibers & other intercellular materials.

Collagen fiber

One of two most common fibers in connective tissue → strength. Imbedded in ground substance

Connective tissue proper

Encompasses all organs & body cavities connecting & separating → areolar (loose), adipose (fat), & dense regular tissue.

Areolar (loose) connective tissue.

Most widespread → attach skin to underlaying tissue, fills space between organs & holds them in place, cushions & protects them. Surrounds & supports blood vessels.

Adipose (tat) tissue

Large internal fat droplet that pushes cytoplasm into thin layer & nucleus is at edge of cell → storage for lipids, pads & protects, & insulates.

Specialized connective tissue

Cartilage, bone, & blood. Cartilage & bone form skeletal framework. Blood is vascular (transport) tissue.

Cartilage

Elastic, pliable, compact non-vascular. → hyaline, elastic, & fibrocartilage

Lacunae

Traps chrondrocytes in matrix.

Chondrocytes

Cartilage cells.

Matrix

Ground substance → structural support.

Elastic fiber

One of two most common fibers in connective tissue → elasticity. Imbedded in ground substance

Blood plasma

Extracellular matrix → water, salts, proteins, glucose, lipids, glycoproteins, hormones, amino acids, & vitamins.

Erythrocytes

Red blood cells, most abundant, transport oxygen, carbon dioxide, & nutrients. Lacks nodes but has hemoglobin & cytosteletal elements

Areolar (loose) connective tissue

Areolar (loose) connective tissue

Adipose (fat) connective tissue

Hyaline cartilage → trachea