Lecture 3: Cytology and Hystology Flashcards
Prokaryotic
Lack membrane surrounding nucleus
Eukaryotic
Cells contain a membrane-bound nucleus,
Somatic & Sex cells
Somatic Cells
Normal human body cells,
46 in humans (chromosomes)
Sex Cells
Egg & Sperm,
23 in humans
Organelles
Little cellular organs in eukaryotic cell
Plasma Membrane
Double layer of phospholipids embedded with proteins
Diffusion
High concentration of solute to low concentration of solute
Osmosis
Movement of water,
High water concentration to low water concentration
Protein Functions in Plasma Membrane
Anchoring, Recognition, Enzymes, Receptors, Carriers, Channels,
Carbohydrate Functions in Plasma Membrane
Anchoring,
Protection,
Receptors,
Recognition
Facilitated Diffusion
No energy expended by cell,
Decreases the charge and concentration differences between cell exterior and interior,
Automatic reaction from molecular slam dancing
Active Transport
Transports molecules against electrochemical gradient,
Energy in form of ATP,
ATPase Pumps
Sodium-Potassium Pump,
Moves Na+ out of cell and K+ into cell,
Maintains homeostasis from ‘leaky’ cells
Vesicular Transport
Form of active transport (uses ATP) but not against a concentration gradient,
endocytosis,
exocytosis
Endocytosis
Process of cell engulfing a particle/substance,
Phagocytosis,
Pinocytosis
Phagocytosis
Engulfing a solid
Pinocytosis
Engulfing a liquid
Exocytosis
Process of a cell discharging a particle from the plasma membrane
Nucleus
Contains DNA, info, etc,
Surrounded by double-membrane nuclear envelope
Ribosomes
Make Proteins,
Made of RNA and protein,
Large/small subunits,
Found in cytosol (intracellular fluid) and on rough ER
Rough Endoplasmic Reticulum
Folds and modifies proteins that were sent to it
Golgi Apparatus
Packaging and shipping center,
Sends proteins where to go, packaged in vesicles,
Stack of pancakes
Smooth Endoplasmic Reticulum
Fatty acid and phospholipid synthesis for membrane replacement,
Breakdown of hydrophobic toxins
Mitochondria
Powerhouse of cell,
ATP production is it’s core function,
High surface area allows more reactions
Lysosomes and Peroxisomes
Garbage trucks of cells,
Storage and waste processing,
Contains enzymes that breakdown, recycle, clean up waste products of the cell
Cytoskeleton
Gives the cell shape and aids cell movement and transport of materials within the cell,
Actin Filaments,
Intermediate Filaments,
Microtubules
Actin Filaments
Smallest,
Interact w/ myosin to cause cell movements (cell crawling, cytokinesis, cytoplasmic streaming),
Muscle contractions
Intermediate Filaments
Medium,
Defined by size instead of by composition,
Provide structural support for the cell
Microtubules
Largest,
Hollow tubes made of protein that transport vesicles
Centrosomes
Anchor the cytoskeleton,
1 at each ‘pole’ of the cell that contain 2 centrioles,
Help chromosomes split evenly
DNA
Forms a double helix,
Contains all genetic informations for making an organism
RNA
3 kinds,
rRNA,
mRNA,
tRNA
rRNA
Ribosomal RNA,
Forms part of ribosomes
mRNA
Messenger RNA,
Carries message from DNA
tRNA
Transfer RNA,
Brings correct amino acid to ribosomes
Transcription
Reading and copying DNA,
RNA polymerase is the enzyme used
Translation
Ribosomes use rRNA, mRNA, and tRNA to make the proteins from the DNA copy
Genotype
Pairing of alleles
Phenotype
Outward expression of a genotype
Essential Amino Acids
Must be consumed
Nonessential Amino Acids
Can be made in the body
Codon
Groups of 3 bases within mRNA sequence that codes for specific amino acid
Mitosis
Divides cell evenly in 2,
Meiosis
2 Rounds of mitosis without replication,
Results in sex cells with half number of chromosomes
Histology
Study of tissues
Tissues
Collections of cells and cell products that perform specific functions
Epithelial Tissue
Forms surfaces and linings in/on body, Protects, Controls permeability, Provide sensation, Produce specialized secretions Epithelia & Glandular
Epithelia Cellularity
Connections
Gap Junctions
In epithelia,
Allows transfer of ions
Desmosomes
In epithelia,
Glue like connections
Apical
In epithelia,
In contact with external
Basal
In epithelia,
In contact with internal
Epithelia Attachment
Basement membranes anchor tissue to other tissues
Avascular
No blood
Regeneration
Replacement of damaged cells/tissues,
Follows tissue injury,
Fibroblasts produce collagen fibers (scar tissue),
Some tissues heal better than others
Squamous Epithelia
Thin,
Flat,
Scale Like
Cuboidal Epithelia
Square
Columnar Epithelia
Rectangle
Simple Epithelia Layers
Single layer
Stratified Epithelia Layers
Two or more layers
Transitional Epithelium
Can stretch without damage
Exocrine Glands
Release products/secretions through a duct onto an internal or external surface
Endocrine Glands
Release products/hormones directly into blood/tissue fluids
Merocrine
Product released via exocytosis
Apocrine
Product released when apical surface ruptures when full
Holocrine
Product released when cell is full and entire cell ruptures
Connective Tissue Proper
Consists of several cell types within a matrix of fibers and ground substance
Fibroblasts
Make tissue
Fibrocytes
Maintain tissue
Macrophages
WBC,
Phagocyte
Fat Cells
Store energy
Mast Cells
WBC,
Immune/inflammatory responses, releases histamine
Collagen Fibers
Most common
Elastic Fibers
Return to original shape after stretching
Reticular Fibers
Create organ framework
Ground Substances
Thick fluid that surrounds cells and fibers in Connective Tissue Proper,
Slows movement of pathogens
Loose Connective Tissue
Deep,
Separates skin from underlying muscles,
Includes adipose tissue (fat tissue)
Dense Regular Connective Tissue
Collagen fibers are parallel to one another,
Go in one direction,
Tendons and ligaments,
Muscle to bone
Dense Irregular Connective Tissue
Collagen fibers are not parallel,
Form a mesh,
Skin/joint capsules,
Multiple directions
Fluid Connective Tissue
Blood & Lymph
Lymph
Liquid portion of blood that leaves capillaries and is brought back to the blood stream eventually
Supporting Connective Tissue
Cartilage and Bone
Cartilage
Contains living cells called chondrocytes that maintain the cartilage
Hyaline Cartilage
Most common,
Nasal,
Joints,
Rib
Elastic Cartilage
Contains many elastic fibers,
Stretches,
Outer ear,
Epiglottis,
Fibrocartilage
Very tough,
Very little movement,
Intervertebral discs,
Pubic Symphysis
Muscle Tissue
Capable of contraction/allows for movement,
Skeletal (move joints, skin moving on face),
Cardiac (heart, involuntary),
Smooth (involuntary)
Neural Tissue
Conducts electrical impulses from one part of the body to another
Membranes
Layers of a epithelial and connective tissue combination
Mucous Membrane
Secretes mucous,
Lines cavities that communicate with the exterior of the body (digestive, respiratory)
Serous Membrane
Line internal subdivisions of ventral body cavities, Pleura (lungs), Peritoneum (abdomen), Pericardium (heart), Parietal and visceral layers
Cutaneous Membrane
Skin
Synovial Membrane
Decreases friction,
Surrounds synovial joints and secretes synovial fluid
Inflammation
Tissue response to injury and infection,
Mast cells release histamine and heparin,
Local blood vessels dilate,
Local pain sensing nerve endings fire,
Signs of Inflammation (5)
Heat, Redness, Swelling (leaking fluid), Pain, Loss of function
