fully differentiated body parts with specialized functions
groups of different cell types that combine to form a specific function
basic units that make up tissues; sites where changes in structure and function lead to symptoms and diseases
structure that protects the cell by creating barrier that separates intracellular components from extracellular environment surrounding it; comprised of lipids, carbohydrates, & proteins arranged in a bilayer
two interconnected layers
Lipid Bilayer composition
phospholipids (Phosphate PO4-); phosphate connected to the lipid is the head
lipid structure of the lipid bilayer (phospholipid); composed largely of cholesterol; non-polar/hydrophobic
lipid layers align so non-polar tail portions are intertwined and polar heads line both outer and inner surface of the cell
carbohydrate bound to lipid; makes up bilayer but in smaller numbers than phospholipids
Purpose of the bilayer
prevents unintentional passage of water-based substances by hydrophobic cell surface
proteins that pass through the membrane which allow communication and transport between extracellular and intracellular environments
specific type of transmembrane protein that has tight binding to lipid tail and becomes part of membrane itself
allows transport of ions (atoms with electrical charge) across plasma membrane
colloidal substance surrounding cell nucleus; composed of water, proteins, fats, electrolytes, glycogen, and pigments
structures within a cell that perform a distinct function
complex network of tubules, producing proteins & fats; important in regulation of ions within cell; subway-tubular transport system
Rough ER: contains ribosomes; synthesize proteins, produces lysosomal enzymes
Smooth ER: no ribosomes; synthesizes lipid, lipoproteins and steroid hormones regulation of Ca, detoxifies certain drugs & hormones
membrane structure; substances from ER go to GA and are packaged to be transferred out;
prepares substances produced by endoplasmic reticulum for secretion out of cell
GA=Packaging & shipping dept
small sacs surround by membrane; digest cellular debris with hydrolytic enzymes; important in metabolism of particular substances
membrane-enclosed sacs smaller than lysosomes; contain enzymes (oxidase) that neutralize oxygen free radicals; promote cell survival by neutralizing harmful substances potentially damaging to cell
large, recognize abnormally folded or formed proteins; involved in proteolysis (breakdown of proteins)
produces cellular energy source (ATP); contains cytochrome enzymes of terminal electron transport necessary for production of ATP; contains enzymes needed for the citric acid cycle, fatty acid oxidation, and oxidative phosphorylation
Genes vs. Chromosomes
Genes: Individual units of inheritance located on chromosome.
Chromosome: coiled structure of chromatin forms genetic code.
Structure composed of tubule and filament structures that contribute to cell shape, movement, and intracellular transport.
Functions common to all cell types
permits transport of some substance but acts as a barrier to others
Substances enter cell passively with little energy required.
Diffusion (movement from higher to lower concentration) is an example of Passive Transport.
movement from higher concentration to lower
membrane passage between extracellular and intracellular environments
movement of some substances across membrane that need help of transport proteins for passage
channel that opens without the need for stimulation
channel that opens in response to stimulation
stimulated by receptor-ligand binding
stimulated by vibration, stretching, and pressure
requires energy when transporting particles across membrane such as sodium potassium pump
Primary Active Transport
process requiring direct use of energy (ATP)
Secondary Active Transport
movement of a second substance depends on energy derived from active transport of primary substance
Contransport or Symport
systems in which substances are transported in same direction
Countertransport or Antiport
movement of substances in opposite directions
process used to transport large substances into cells;
Pinocytosis - ATP requiring process of ingesting small vesicles;
Phagocytosis - process of ingesting large particles such as cells, bacteria, damaged cell components
vesicles move from Golgi into cytoplasm and then out of cell via cell membrane
series of metabolic processes that transforms fuel molecules into energy (ATP) and waste products
process of ATP production that occurs without oxygen
chemical reactions of oxidation and reduction between oxygen and nutrient products such as glucose
process of breaking down glucose in cytosol of cells; occurs in absence of oxygen, releasing only small amount of energy
regulates gene activation to tightly control production of proteins and prevent cell damage caused by overproduction or underproduction
signaling molecule; when ligand binds to receptor, it begins process of communication known as signal transduction pathway
tightness or strength of binding
Paracrine Signaling / Local Mediators
ligand receptor binding that results in signal transduction with a local effect
wider range of impact occurs when signal transduction affects cell behavior within entire organism
ligands involved in endocrine signaling; process is slower and longer lasting than paracrine signaling
increase in cell number
changes in physical and function properties of cells, directs cells to develop into specific cell types
Responses to Stressors on Cells
adaptation or death;
mechanisms promote cell adaptation result from signals that cause changes in gene function; changes can be in size, number or structure
decrease in size of a cell
Why does atrophy occur?
decrease in functional demand (limb in cast);
decrease in oxygen supply to cell (ischemia);
involution (removal of hormonal signals that stimulate growth)
increase in cell size usually from trophic or growth signals
increase in number of cells caused by hormone signaling
- High altitudes increase blood cells
changing of one cell type to another;
adaptation can occur: for example, people with GERD have the cells of the esophagus change from squamous epithelium to glandular cell type. Also bronchial tube cells change to adapt in smokers.
Refers to the actual change in cell size, shape, uniformity, arrangement and structure. In response to a chronic persistent stressor and is likely to resolve when the stressor is removed.
condition where stressors prompt cell alteration leading to chronic, irreversible tissue changes.
Caused by infants who need mechanical ventilation with high concentrations of oxygen.
Bronchial and alveolar tissue become thickened and reduce air into lungs
physiologic and pathologic cell response to cellular signals. (A programmed cell death prompted by a genetic signals an is designed to replace old cells with new.
AKA Cellular suicide.
Could be due to damaged genetic material/mutation
Old age of the cell
fusion or incomplete separation of digit soft tissue. This is an alteration in process of apoptosis.
death of cells related to injury
Some Causes of Injury to Cells
Endogenous (toxins from within the body)
Deficit injury (such as oxygen deprivation)
Common Causes of Cell Injury & Death
Toxins (chemical, pathogenic)
Physical injury (mechanical, chemical, thermal)
Serum deficit injury (nutrition, hydration, oxygenation)
reduction in size of the cells in the cerebrum of the brain; progression leads to reduction in brain tissue
AKA Hypertrophic Cardiomyopathy
Disease of cardiac muscle that results from excessive workload and functional demand
Most common cause of sudden unexpected cardiac death in young individuals (< 30 yrs of age)
Reactive Oxygen Species (ROS)
toxic oxygen molecules or radicals that are formed by the reaction between oxygen and water during mitochondrial repiration.. Cell damage results from too many ROS or not enough available enzymes.
ROS damages DNA
Contributes to many diseases such as heart disease, diabetes, cancer
ROS AKA Free Radical Injury
Cerebral Atrophy's Effect on Neurons
Frontal & Temporal lobes: cognitive impairment
Hippocampus and cerebral cortex: Alzheimer's disease
Basal Ganglia: Movement disorders
Recovery is severely limited due to the inability of neurons to replicate.
Cause of Secondary Cardiac Hypertrophy
increased blood pressure resulting in increased workload on the ventricle
Primary Cardiac Hypertrophy Without Known Cause
inherited non-sex linked genetic autosomal-dominant trait
ability of the ventricle to contract without rigidity
Resting Left Ventricular Outflow Obstruction
When systolic pressure gradient reaches 30 mm Hg. It is moderate when it reaches 50 mm Hg or severe when it reaches 75 mm Hg.
Rx for Secondary Cardiac Hypertrophy
as soon as it manifests and before cells undergo permanent damage.
Treatment is geared toward relaxation of the ventricle and relief of the outflow obstruction.
Antihypertensive meds are used to lower resistance in left ventricle when hypertension is the cause.
Condition of hyperplasia caused by hormone stimulation of excessive growth.
Manifested by abnormal growth of the hands and feet in people how have stopped growing (epiphyseal ossification occurs)
Usual Cause of Over-secretion of GH in Adults
pituitary tumor called an adenoma.
Same condition as Acromegaly but it occurs in youngsters
prior to the closure of epiphyseal growth plate.
Acromegaly, manifestations of
Altered facial features
Prominence of jaw, brow
Enlargement of tongue and lips
Pain & numbness in hands
Altered reproductive functioning
Rx for Acromegaly
Surgical removal of adenoma
Chronic effects can be halted if identified early before permanent cell injury occurs.
Cells of the Cervix
Squamous epithelium (outer side of cervix & vagina)
Columnar epithelium (lines the endocervical canal)
Location at which the two types of cells merge. This area is dynamic throughout a woman's repro life, migrating and changing location on the cervix in response to stimuli such as hormones and pH.
The area where the cells types merge is called the transformation zone.
Adaptations that these cell types undergo, changing from one type to another type of cell in response to environmental stressors.
Metaplastic changes of the cervix are not pathologic, the squamous epithelial cell component of the transformation zone is vulnerable to stressors which may cause the cells injure or damage.
Causes of Injury to Epithelium
considered a precancerous condition
Cervical Dysplasia - S&S
Cervical Dysplasia - Risk Factors
Early-onset sexual activity
Multiple (more than 3 sexual partners)
Exposure to human papilloma virus (HPV)
Rx for Dysplastic Ectocervix Cell
Cone biopsy/conization (with scalpel)
Large-loop electrosurgical excision (LEEP)
Cellular Damage - most common environmental cause
Hormone Process that causes Growth (gland & hormone)
Hypothalamus - GHRH
Pituitary - GH
Liver - Insulin-like growth factor 1 (1GF-1)
Hypothalamus - Somatostatin AKA GHIH
Hormone Process that causes Growth (gland & function)
Pituitary - causes cell cycle control responses/proliferation of cells;
Liver - promotes growth of bone, cartilage, soft tissue and organs;
Hypothalamus - Suppresses GH
Hormone Process that causes Growth (gland & stimulates)
Hypothalamus - pituitary to release GH;
Pituitary - liver to produce insulin-like growth factor 1 (1GF-1);
Liver - hypothalamus to produce somatostatin AKA GHIH;
substance microscopically dispersed evenly throughout another substance