Human Bioscience

OD 1 Fall Semester Human Bioscience Lecture Flashcards

Basic Principles of Histology?

Body is made of 4 types of tissues: Epithelium, Connective Tissue, Muscle, Nerves… Can also think of Gametes and Embryonic Stem Cells

Epithelium Overview

Covers and Lines tissue, High Cell Density, Little Intercellular Space

Epithelium Functions Overview

Barriers, Absorption, Secretion

Layers of Epithelium

Apical (outer), Basal (inner), Basement Membrane (outside cells - attaches epithelial cells to underlying CT)

Connective Tissue Overview

Low cell density, Excessive Extracellular Matrix (with collagen, elastin, immune cells, etc)

CT Functions Overview

Storage, Structural (holds things tg), Immunological

Types of CT Overview

Connective Tissues (softer), Cartilage, Bone (hardest), Blood (fluid form)

Nerve Tissue Overview

Rapid Cell to Cell communication, Excitable cells that experience changes in membrane potential for either Graded potentials or APs, Synaptic Transmission, Sensory motor integration, Glia - functional support

Muscle Overview

Excitable cells, Contractions, Several types, Effectors, Sensory motor elements

Other effector tissues?

Muscle, Endocrine Glands

Tissue types are categorized by…

Structural and Functional Characteristics

Structural Characteristics

Cell shapes and organizations, Extracellular matrix

Functional characteristics

Storage, protection, absorption, secretion, support, sensory, communication, contraction

Endothelium

specialized subtype of epithelium that lines internal capillaries, blood vessles, and lymphs

Simple Squamous Epithelium

1 single cell layer, flat/packed together, apical/basal side with basement membrane,

Dense Irregular Connective Tissue

Irregular due to unorganized collagen, loaded with collaged, houses capillaries lined with endothelium

Unilocular Adipose Tissue

Storage connective tissue, adipose filled “bubbles” that has dissolved fats inside. Blood will store and pickup adipose from this connective tissue as needed

Where are all tissues derived from

Embryonic stem cells organized into germinal epithelia

Ectoderm derives…

skin and nerves

Endoderm derives

gut and organs that in gastrointestinal tract, lungs, etc

Mesoderm

Connective tissue, bone, muscle, other organs

Organs are composed of…

many tissue types

Skin layers

Epidermis (epithelium)

Dermis (connective tissue)

Hypodermis (connective tissue)

Ocular tissue can be simply categorized into which three layers?

Fibrous tunic

Vascular tunic

Retina

Fibrous Tunic

Sclera, Cornea

Vascular Tunic

Iris, Ciliary body, Choroid

Retina

Pigmented layer (retinal pigment epithelium - top layer), Neural layer (neural tissue)

Which tissues are found in the eye?

All 4 types: CT, Epithelium, Neural, Muscle

Eye epithelium

Cornea, Ciliary Processes, Lens, RPE

Eye CT

Cornea, Iris, Choroid, Sclera

Eye Neural

Retina, Optic nerve

Eye msucle

ciliary muscles, iris, choroid

Cornea Layers

Corneal Epithelium (5-6 layers and dense) —> Corneal Stroma (CT, less dense with lots of ECM) —> Corneal Endothelium (inner layer with basal, basement, and apical sides)

Rank from most superficial to deep: RPE, Choroid, Sclera, Ganglion Cells, Photoreceptor Cells, Retina

Sclera, Choroid, RPE, Photoreceptor Cells, Ganglion Cells, Retina

Visualization of structure and function: Perspective

Size, Orientation, 3D structures in 2D representation

Red Blood Cell Size

7um

Light Microscopy: Staining

Hematoxylin and Eosin, Special stains, Immunohistochemistry, In situ hybridization

Hematoxylin and Eosin

most common stain - differential

Hemtoxylin - purple color staining nucleus

Eosin - pink color staining ECM/cytoplasm

Special Stain example

Trichrome stain- Keratin on outer skin surface, red dots is nuclei with cytoplasm

Fluorescent stain

antibodies with fluorescent markers:

Dapi (blue) - stains nuclei of cells

Green - stains actin

Red - stains cell/plasma membrane

Immunohistochemistry

use of antibodies —> different muscle fibers staiin different colors depending on speed at which enzymes cause contractions of fibers

in situ hybridization

stains to see function —> red dots usually indicate synthesis of specific proteins

Electron microscopy

higher resolution and magnification visualization

Transmission EM

cut thin section of cells —> scan ultra thin sections