Lecture 2 Flashcards
Nucleus
Contains genetic information; directs the metabolic function of cells; Nuclear membrane/pores; allows communication with cytoplasm
Cytoplasm
Surrounds nucleus; structures carry out directions of the nucleus, carry organelles, and surrounded by a selectively permeable cell membrane
Cell
Basic structural and functional unit of the body (building blocks, there are over 200 types and trillions in your body)
Tissues
Group of similar cells performing the same functions
Organs
Groups of tissues
(ex. the heart)
Organ systems
Groups of organs functioning together (ex. the nervous system or the cardiovascular system)
Functioning organisms
Integrated organ systems (humans, animals, etc.)
What is the organization of the cell? (smallest to largest)
Cells, Tissues, Organs, Organ Systems, Functioning Organism
What happens if there is an abnormality at any level of cell organization
Disease
Juxtacrine signalling
Cell-to-cell communication by direct contact
Paracrine signalling
Cell-to-cell communication by soluble mediators acting near groups of cells
What is a cell structure made up of?
Nucleus, Cytoplasm and it’s elements
What is found in the cytoplasm?
Organelles such as Nucleus, Mitochondria, Endoplasmic reticulum, Golgi apparatus, Lysosomes, Centrioles, Cytoskeleton
Endocrine signalling
Cell-to-cell communication by direct contact through soluble mediators acting across a distance
Receptor
Cell surface signal
Organelle
A small structure present in the cytoplasm of the cell, such as a mitochondrion
DNA
The nucleic acid present in the chromosomes of the nuclei of cells that carries genetic information
Chromosome
Cell structure organizing the molecules of DNA. Individual structural units of DNA which are best seen in dividing cells
Chromatin
Tightly wound DNA in the nucleus; formed in part from nucleosomes
Nuclear membrane
Double-layered; with pores; separates the nucleus from the cytoplasm
Ribonucleic acid (RNA)
In nucleoli; components of messenger, transfer, ribosomal RNA
Nucleoli
Spherical Intra-nuclear structure in the nucleus that contains RNA (sing. nucleolus)
Nucleosome
Basis of packaging DNA
Histones
Nuclear proteins forming the nucleosomes
Alcohol steatosis
“fatty liver”; excessive alcohol can lead to an abnormal intracellular accumulation of lipids in the liver
Mitochondria
Rod-shaped structures capable of converting food material into energy to manufacture adenosine triphosphate (ATP) that fuels chemical reactions in the cell
Endoplasmic Reticulum (ER)
Interconnected network of tubular channels enclosed by membranes. Involved in communication with the nuclear and cellular membrane
Rough ER
Ribosomes are attached to the external surface; responsible for protein synthesis
Smooth ER
Contains enzymes and is responsible for lipid synthesis
Ribosomes
small site for protein synthesis that are attached to ER but may also be free in the cytoplasm
Golgi apparatus
Flat sacs located near the nucleus attach carb molecules to the proteins synthesized by RER
Protein pathways from RER to GA
The protein produced by ribosomes attached to the RER –> RER tubules transport these proteins to the Golgi apparatus –> combine proteins with carbohydrate molecules in GA –> forms secretory granules
Lysosomes
Cytoplasmic vacuoles with digestive enzymes (prevents leakage of enzymes)
Peroxisome
Enzymes that decompose hydrogen peroxide (any waste in the cell)
Centrioles
Short cylindrical structures adjacent to the nucleus (involved in cell division)
Cytoskeleton
Form cell’s structural framework, shape, and cell movements; 3 types of protein tubules (mostly intermediate filaments)
3 types of protein tubules
- Microtubules (largest) ex. a/b tubulin polymers
- Intermediate filaments ex. vimentin/keratin fibers
- Microfilaments (smallest) - G actin polymers, can generate force
How does the intermediate filaments help in providing diagnostic and prognostic information?
It helps in looking for diseases (ex. Alzheimers and cancer - cell of origin) and treatment for them
Selectively permeable
Only lets certain molecules enter and exit and it controls traffic into or out of the cell (ions/inorganic molecules)
What is the cell membrane composed of?
Lipid bilayer, glycoproteins, glycolipids, receptors, ion channels/transporters, Carbohydrates
CF-CFTR protein
Controls flow of Water and chloride ions across the cell membrane
Diffusion
Solutes move from concentrated → dilute solution (high to low)
Osmosis
Water molecules move from dilute → concentrated solution (low to high concentration)
Hypertonic
Water leaving (cell deflates)
Isotonic
Water leaving and entering cell is equal (optimal)
Hypotonic
Water entering (cell explodes)
Active transport
Movement from low concentration to high concentration (active meaning it requires energy)
Sodium
Electrolyte found extracellularly
Potassium
Electrolyte found intracellularly
Phagocytosis
Ingestion of particles too large to pass across the cell membrane (Large particles)
Endocytosis
Internalization materials by engulfing (small particles)
Pinocytosis
Ingestion of fluid and very small molecules/ions
Exocytosis
Remove wastes/ products (hormones, enzymes) from cells from secretory vesicles from Golgi apparatus
What are 4 types of tissues?
Epithelium, Connective and supporting, Muscle, Nerve
Epithelium
Covers the exterior of the body, lines interior body surfaces to communicate with the outside (GT, UT, Vagina), and forms glands + parenchymal cells excretory or secretory organs (liver and kidney); contains no blood vessels and gets its nutrients from diffusion
Epithelium function
Protection, absorption, secretes mucus, sweat, oil, enzymes, hormones
Exocrine glands
Discharge secretions through a duct
Endocrine glands
Discharge secretions directly into the bloodstream
Endothelium
Layer of simple squamous epithelium – lines inside of heart and blood vessels
Mesothelium
Layer of simple squamous epithelium that lines pleural, pericardial, and peritoneal cavities
Simple Squamous
Direct contact with basement membrane (absorbtion/filtration) capillary walls, alveoli walls
Simple Cuboidal
Absorption/secretion/excretory functions kidney, pancreas
Simple Columnar
Absorption/secretion/excretory
Stomach/ colon/ rectum
Stratified Pseudo
Ciliated (mucous secretion/protection) upper airways/trachea
Stratified Transitional
Elastic organs (bladder, urethra)
Stratified Squamous
Protective (Esophagus/mouth/Vagina)
Types of connective tissue fibers
Collagen fibers, Elastic fibers, Reticular fibers
Collagen fibers
Found in joints and skin (most abundant protein)
Elastic fibers
Found in blood vessels, lungs, and skin (contains elastin protein)
Reticular fibers
Form supporting framework of organs (liver, spleen)
Similar to collagen but thin and delicate
Hematopoietic
Immature cell that will form into any blood cell
Lymphatic
Lymphocyte forming
Adipose tissue
Insulation, energy, padding
Cartilage types
Hyaline, Elastic, fibrocartilage
Subcutaneous tissue
Support/protection of organs and muscles (deepest skin layer)
Actin
Globular multi-functional proteins that form microfilaments in the cytoskeleton
Myosin
Motor protein pulls actin filaments
Striated muscle
Moves skeleton and under conscious control (skeletal muscle)
Smooth muscle
Located in walls of hollow internal organs (function under unconscious control)
Cardiac muscle
Found in the heart
Neurons
Nerve cells, transmit nerve impulses
Central body
dendrites (transmit toward cell body) and axon (transmit away) emerge from it to transmit impulses
Neuroglia
Supporting cells more numerous than neurons (provide protection)
Astrocytes
Long, star-shaped cells, numerous, highly branched process; Provide structure/support and nourishment to neurons
Oligodendrocytes
CNS; Small cells, scanty cytoplasm, surround nerve cells (myelin) - Schwann (PNS)
Microglia
Phagocytic cells – immune protection; Macrophages of NS
Parenchymal cells
Primary functional cells of an organ
Parenchyma
Functional cells of an organ
Stroma
Tissue that forms the supporting framework of an organ
Trophoblast
Peripheral group of cells; forms placenta and other structures to support and nourish embryo
Inner cell mass
The inner group of cells; will give rise to the embryo; arranged in three distinct
Ectoderm
Outer layer becomes external covering of body that will interact with external environment (skin, nervous system, ears, eyes)
Mesoderm
Middle layer (connective tissue, muscle, bone, cartilage, heart, blood, blood vessels, and major portions of urogenital system)
Endoderm
Inner layer (epithelium of pharynx, respiratory tract, liver, biliary tract, pancreas, some parts of urogenital tract)
Atrophy
Reduction in cell size in response to: Diminished function, Inadequate hormonal stimulation, Reduced blood supply
Hypertrophy
Increase in cell size without increase in cell number
Hyperplasia
Increase in both cell size and number in response to increased demand
Metaplasia
Change from one type of cell to another
Dysplasia
Cell development and maturation are disturbed and abnormal
Cell necrosis
Irreversible damage causing cell damage and leading to cell death (not all dead cells are necrotic)
Apoptosis
Programmed cell death
Hayflick limit
Damage/shortening ends of telomeres with each division
Autophagy
Cellular organelles are degraded and recycled by the cells
Keratin filament
Type of filament in epithelial cells
Vimentin filament
Type of filament in connective and muscle cells
Neurofilaments
Type of filament in nerve cells
Lamin filaments
Found in the nuclear structure of all cells
Anaplastic cells
Tumor cells who’s structure is deranged
Mesoderm
Embryonic germ layer
