Lab 2: Cells, Cell Cycle & Epithelium Tissues Flashcards
(58 cards)
What are the 4 types of tissues?
epithelium, connective, nervous & muscle
2 classes of epithelial tissues and their functions
- Membranes/ covering & lining epithelium: Prevents things from coming inside
- Glandular epithelium:
Removes materials from the blood
Overall function of epithelial tissues
protection, absorption, secretion, filtration & sensation
Unique features of epithelial tissues
polarity, specialized contacts, supported by connective tissue (basement membrane), avascular but innervated (no blood supply, diffusion, supplied by nerves) & regeneration
SIMPLE SQUAMOUS function, description & location
- Description: 1 layer (thin/short); squared (little flat rocks on top); close up – flat nerds rope (nuclei = nerds)
- Function: diffusion, filtration & secretion
- Location: AIR SACS OF LUNGS, kidney, lining of heart, blood vessels, lymphatic vessels & ventral body cavity (serosae)
SIMPLE CUBOIDAL function, description & location
- Description: 1 layer; 3d cubes on top; close up – donut
- Function: secretion & absorption
- Location: KIDNEY TUBULES, ducts, small glands & surface of ovary
SIMPLE COLUMNAR function, description & location
- Description: 1 layer; white house columns on top (tall); close up – hairy (cilia) & slimy (mucus) cucumber slice
- Function: absorption, cilia propels mucus, and secretion of mucus & enzymes
- Location: SMALL INTESTINE, digestive tract (stomach → rectum), gallbladder, small bronchi & uterine tubes
PSEUDOSTRATIFIED COLUMNAR function, description & location
- Description: appears stratified (fake); the bottom is still 1 layer (simple) & has cavities (thin/packed/busy white house); close up – ciliated city (hairs at ends of cell image; different heights/levels of nuclei)
- Function: secretes mucus & cilia propels mucus
- Location: TRACHEA (upper respiratory) & sperm
STRATIFIED SQUAMOUS function, description & location
- Description: many blurry rocks piled on top of each other; close up – dark & dense → light & scattered seeds on the outside (cells are full of keratin & dead)
- Function: protects underlying tissues
- Location: nonkeratinized → LINING OF ESOPHAGUS, mouth & vagina; keratinized → epidermis of skin (dry)
STRATIFIED CUBOIDAL function, description & location
- Description: 2 layers of 3D cubes; close-up – ring (basement membrane & duct lamen on the inside)
- Function: protection
- Location: largest ducts of sweat glands, mammary glands & SALIVARY GLAND
STRATIFIED COLUMNAR function, description & location
- Description: 3 layers of 3D cubes & has long white house columns with cavities; close up – light & scattered → dark & dense seeds on the outside
- Function: protection & secretion
- Location: MALE URETHRA & large ducts of some glands (rare)
TRANSITIONAL function, description & location
- Description: relaxed state; more defined rocks stacked on top of each other; close up – rounded petals like a flower on the ends (resembles stratified squamous & cuboidal)
- Function: STRETCHES & distension/swelling of urinary organ
- Location: BLADDER, urutera & urethra
Endocrine vs Exocrine
- Endocrine → lose duct, secretes hormones into extracellular fluid, which enter blood stream & lymph (inside)
- Exocrine → retain ducts, secrets to body surface or into body cavities (outside)
Telophase key events
Begins when chromosomes stop moving, reverse prophase, identical set of chromosomes at opposite poles of cell uncoil → threadlike chromatin form, nuclear envelope & nucleoli appear & spindle disappears; 2 nuclei identical to mother.
Anaphase key events
Centromeres (lead the chromosomes) split simultaneously causing chromatid → chromosome (“V”), kinetochore microtubules PULL each chromosome TOWARD ITS POLE, microtubules push the 2 poles apart, chromosomes = short & easy to move (leaves middle open)
Metaphase key events
centromeres are at opposite poles of cell (@ equator of spindle), chromosomes LINE UP IN MIDDLE of cell, metaphase plate sits between the pulling & enzymes separate chromatids from each other
Prophase key events
chromatin condenses to form chromosomes which interact with spindle microtubules, each chromosome has identical sister chromatids @ centromere, nucleoli & nuclear envelope disappear/break up, mitotic spindle, centrosomes are pulled to opposite poles of cell, asters are present & kinetochore microtubules play TUG OF WAR using the chromosomes which brings the chromosomes to the equator of the cell.
Interphase key events
- Cell growth & normal metabolic activities
- DNA = chromatin
- A nuclear envelope & 1 or more nucleoli are visible
3 Periods of Interphase & Key Events
G1 → centrioles begin replicating
S → DNA is replicated
G2 → centrioles finish replicating
When does MEIOSIS occur and what does it produce?
Meiosis is only for sexual reproduction & produces daughter nuclei that are all genetically different from the mother
What is an issue of the cell cycle?
When there is an uncontrolled division of cells, a tumor develops which leads to cancer.
What is cytokinesis & when does it occur?
Division of cytoplasm & occurs at the end of mitosis
What is MITOSIS & what does it create?
Division of copied DNA (mother cell’s DNA) & makes 2 daughter nuclei that are both identical to mother
What happens before the cell divides?
DNA replicates
