Flashcards in Chapter 3 Deck (64)
What differentiates mature cells from immature cells?
Differentiation - mature cells are more specialized.
What is a fertilized ovum?
It is a zygote
Name two large cells
Fertilized zygote and anterior horn cell
What is are the components of a mature cell? Is there an exception?
Nucleus, Cytoplasm, and Cell Membrane.
An exception would be mature red blood cells. Immature red blood cells have a nucleus however it is lost by the time its matured.
What are eukaryotic cells ?
Organisms with a nucleus.
What is a nucleus and what does it contain ?
Large spherical organelle with a double membrane with pores that allow substances into and out of the cell. It contains DNA
A region in the nucleus with no surrounding membrane is called the nucleolus which produces ribosomes (site of protein synthesis).
There is also chromatin - uncoiled DNA and protein - histones. When chromatin condense theyre called chromosomes.
The fluid in the nucleus is the nucleoplasm.
What is the cytoplasm?
The inside of a cell. It is made up of cytosol - fluid portion and organelles.
What is the mitochondria?
Powerhouse of the cell. Produces energy for the cell. Has a double membrane with folds on the inner membrance called cristae. ATP is produced in the inner membrane.
Mature red blood cells have no mitochondria.
Also have DNA and direct the synthesis of some proteins
What are ribosomes?
Responsible for protein production . Made up of RNA. Do not have a membrane, assembled in the nucleolus. Are found free in the cytoplasm or bound to the ER
What is the endoplasmic reticulum?
Network of channels having a single membrane. Connected to the nuclear envelope, cell membrane, and organelles.
rER - has ribosomes attached to it. Synthesize and process proteins, take them to the Golgi apparatus . Found mostly in endocrine glands that secrete hormones.
sER - has no ribosomes, involved with lipid synthesis and detoxification . Found in the liver .
What is the Golgi Apparatus?
System of stacked membraneous sacs cisternae - look like stacked bowls decreasing in size.
Process, package, and transport proteins made in the rER. When done processing the protein is wrapping in a vesicle to be pushed out of the cell by exocytosis.
Difference between Lysosome and Perioxisome?
Lyso- Small, membrane bound . Contain lytic enzymes that can destroy / digest proteins, carbs, etc
Per - Similar but contain peroxidases. Help to break down peroxide , help with detoxification . Found in the liver.
What are Cilia?
Hairline strands outside the cell membrane. Help to propel material throughout the body. Found in mucus membrane
When people smoke they can damaged, therefore particles cannot be moved up the respiratory tract causing the coughing.
What are Flagella?
Like cilia but longer. Found in sperm cell and responsible for mobility.
What are centrioles?
Cylinderical organelles near the nucleus. Have spindle fibres attached to them . Help to pull chromosomes apart during cell division.
What is the cell membrane? What are its characteristics?
Made up of two phosolipid layers - hydrophilic heas pointing outwards and hydrophilic tails pointing in wards.
It is semi permeable
What is passive transport? Different types?
Involves no energy. Molecules move from area of high concentration to area of low concentration
Simple diffusion - lipid soluble substances like O2, CO2 move down the concentration gradient - area between high and low concentration. Movement does not stop, when equilibrium is reached - movement constant
Facilitated Diffusion - Not lipid soluble - K, NA, GL. Need a carrier to move around.
Osmosis - Diffusion of H2O from low to high concentration. If more solid in the cell then inside is hypertonic, outside is hypotonic. If concentration equal then isotonic
Filteration - Molecules move across a membrane due to pressure on the side where the molecules are leaving.
What is active transport?
Requires energy . Molecules move from low to high concentration.
Endocytosis - Formation of vesicle
Phagocytosis - When larger molecules are brought into the cell
Phinocytosis - Liquid brought into the cell.
Exocytosis - Secretion of protein hormones in endocrine glands
Transcytosis - when endo and exo are happening at the same time
NaK pump - Na out of cell and K into . High Na concentration outside the cell, and high K concentration inside the cell . Happens in nerve cells after passage of impluse.
What is interphase?
When the cell is getting ready for mitosis or replicating DNA
What is mitosis?
Cell division and replication. Resulting in two daughter cells with same number and kind of chromosomes as the original nucleus
What is prophase?
First phase. Chromatin condenses to form chromosomes. Each chromosome has two identical sister chromatids joined by a centromere. Centrioles - microtubles move to the opposite ends of the cell forming spindle fibres that attach to the centromeres of the chromosomes.
What is metaphase?
2nd phase. Chromatids line up in the middle or equatorial plate
What is anaphase?
3rd phase . Spindle fibers joining the centromere to the centrioles shorten shorten and move the sister chromatids to the opposite ends of the cell.
What is telophase?
Final phase. Formation of nuclear envelope . Chromosomes unwind to form chromatin. The cell is ready to divide.
What is cytokenesis?
Actual division of the cell. It starts at late anaphase and continues in telophase.
What is Meiosis ?
Cell division required for reproduction - ova and sperm . Instead of 2 identical daughter cells it produces 4 functional sperm cell in men and 1 egg and 3 nonfunctional polar bodies in women .
What is regulation?
The number of times a cell can divide (50-75).
Labile cells - constantly dividing eg - bld cells, skin
Stable cells - dividing when needed - hepatocytes
Permanent cells - cannot multiply - neuron
What are stem cells?
Cells that can become a variety of cells
Embryonic Cells - derived from embryos that develop from eggs fertilized in vitro not taken from eggs fertilized in a womans body
Adult stem cells - present in most organs or tissues in body
What is the major difference between embryonic and adult stem cells?
Embryonic stem cells are totipotent - they can develop into any cell type.
Adult stem cells can only develop into specialized cells of a specific tissue or organ .
What is cell death?
Normal occurrence also known as apoptosis. Programmed cell death. Method of destroying cells that may have mutated and pose a danger of becoming cancer
What is necrosis?
Premature cell death - always pathological.
A myocardial infarction results in death of cardiac muscle cells.
What is epithelial tissue?
Lines body cavities, organs , surfaces etc.
Avascular (lack a blood supply), shed without blood loss and receives nutrients from blood vessels in underlining connective tissue.
Has a basement membrane which separates epithelial tissue from connective tissue.
Has a nerve supply and is labile.
What is simple squamous epithelium?
Flattened - only one cell lays in thickness
Functions - Easy passage of substances through the membrane through diffusion , filtration
Found in lungs for easy exchange of oxygen and co2
What is stratified squamous epithelium?
Fuction - protective function, protects against abrasion
stacked in several layers . Tightly packed ,held together by cell junctions.
Found in oral cavity, vagina, anus, esophagus
What is simple cubodial epithelium?
Arranged in single layer - cubodial shaped .
Function- Secretes and adsorbs
Found in kidney and glands
What is simple columnar epithelium?
These cells are taller than they are wide. Arranged as single layer .
Fuction - Involved with secretion of mucous and enzymes and absorption , seen in the digestive tract.
Some have special structures on them cilia - to move subtances, microvilli - to increase surface area, goblet cells to secrete mucus for protection . Found in bronchi, bladder
What is stratified columnar epithelium?
Fuctions- secretes and protects
Not common- found in male reproductive tract and pharynx
What is psuedo stratified columnar epithelium?
Give appearance of being stratified, but arent.
Found in respiratory tract. Have ciliated tissue
Goblet cells are specific cells that produce mucin which help form mucus which traps debris
Function- secrete mucous, ciliated tissue move mucous
What is transitional epithelium?
Cubodial with modification of apical - surface. The apical is domed or curved to ensure the epithelium doesnt rip when stretched or expanded . Found in thr urinary bladder, ureters, urethra .
What is stratified cubodial tissue?
Found in sweat glands, salivary glands
Function - protective tissue
What is Glandular or Secretory Tissue?
Specialized cell that secretes digestive juices, hormones, milk , perspiration and wax
Columnar or cuboidal shaped
What are mucous or serous membranes?
Simple squamous cells lines certain internal and external cavities of the body, forming a smooth, transparent, two-layered membrane lubricated by a fluid derived from serum
Internally-e.g.-The mucus in digestive tract protects the lining of the stomach and small intestine from digestive enzymes
Externally- protects the body from drying out, from injury and bacterial invasion
What is MUCOSA?
term used for specific mucous membrane
respiratory mucosa -lines respiratory passage
gastric mucosa -lines stomach
intestinal mucosa- lines small &large intestine
What is serious membrane?
A double-walled membrane that produces a watery fluid (serous fluid) and lines close body cavities
Outer membrane-parietal membrane
Inside membrane-Visceral membrane
The fluid allows organs to move freely and prevent friction
What is SEROSA?
SEROSA-term given to certain serous membrane beginning with “p”
Pleural membrane-lines the chest cavity (thoracic) and protect the lungs –pleural fluid
Pericardial membrane-lines the heart cavity and protects the heart- pericardial fluid
Peritoneal membrane –lines the abdominal cavity and protects the abdominal organs- peritoneal fluid
What is Blood?
Cells and a non-living matrix are the plasma
Erythrocytes, leukocytes, and thrombocytes (platelets) that are cell fragments
Transport of gases, nutrients and wastes, as well as immunity and blood clotting
What is bone?
Supportive Connective Tissue
Extremely hard (calcified) matrix composed of mineral salts (calcium carbonate & calcium phosphate) deposited around collagen fibers
Osteocytes , osteocytes, and osteoclasts are bone cells
Supports and protect underlying soft tissues and organs -strength
Attachment for skeletal muscle, hematopoiesis, and storage for certain chemicals
What is Cartilage?
Cartilage: dense connective Tissue
Support, protect, and act as a framework for bone development
Three types of cartilage:Hyaline cartilage, Elastic cartilage, Fibrocartilage
What is Hyaline cartilage ?
Most common type
Contains only collagen fibers
Found in the nose tip, bronchi, ends of long bones, ribs, larynx and in the supporting rings of the trachea
Forms the skeleton of the embryo
What is Elastic cartilage ?
Matrix contains many elastic fibers; also contains collagen fibers; more flexible than hyaline cartilage
Found in the outer ear, epiglottis and larynx
What is Fibrocartilage?
Matrix contains strong collagen fibers
Absorbs shock and reduces friction between joints
Found between the vertebrae and in the knee joint
What is connective tissue?
Most abundant and widely distributed tissue in the body
Support and connect the organs of the body
Produces blood cells, and stores fat
Found in bones, cartilage, mucus membrane , muscles, nerve, skin and all internal organs
Defined as tissue made up of living cells and a non-living matrix
Matrix is the material between the cells and is made up of water, salts, proteins, fibers, and other substances
What is loose connective tissue?
LOOSE (areolar) Fibrous Connective Tissue
Semi fluid matrix that ssurrounds various organs
Supports nerve cells and blood vessels
Temporarily stores glucose, salt and water
Mainly fibroblasts cells (large , star shaped, fiber producing cells), Areolar tissue, adipose (fat) tissue, and reticular connective tissue
What is regular dense connective tissue?
In dense regular connective tissue the bundles (collagen) are parallel (as in tendons and ligaments)
Tendons-connect muscle to bone
Ligaments-strong bands that connect bones and hold it together at the joints
Aponeuroses-wide bands holding one muscle to another
Tendons (connect muscle to bone), ligaments (connect bone to bone), and dermis
What is adipose tissue?
Adipose tissue is a type of loose connective tissue in which the adipose cells enlarge and store fat (lipids)
Cushions, support and insulate the body
Found in the subcutaneous skin layer, around the kidneys, heart and in the marrow of long bone
What is irregular dense connective tissue?
Dense irregular connective tissue has fibers that are not arranged in parallel bundles as in dense regular connective tissue. ... Fibroblasts are prodominant cell type scattered sparsely across the tissue.
What is elastic connective tissue?
Ligaments in the spine and the walls of lager arteries, the heart and the bronchi
What is muscle tissue?
Muscle cells are also called muscle fibers or myocytes
Contraction and relaxation of muscles produce movement
Heart and muscle tissue do not repair themselves
What is smooth muscle tissue?
Called visceral or involuntary muscle
Spindle shaped fibers are shorter than skeletal muscle and cells have a single nucleus
Walls of hollow organs like the gastrointestinal tract and uterus
Tapered no striations
What is cardiac muscle tissue?
It has striations, contracts involuntarily, and cells have a single nucleus, intercalating discs
Found only in the heart
What is skeletal muscle tissue
Called striated muscle because of alternating light and dark bands
Fibers are long and have multiple nuclei
Attached to bones by tendons and causes the bones to move
What is cutaneous membrane?
Cutaneous membrane (skin)
Forms the outer covering of the body
Consists of an outer portion of keratinized stratified squamous epithelium attached to a thick layer of dense connective tissue
What is inflammation?
a protective response to an injury causing pain and swelling