Term
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Definition
-The fundamental unit of life.
-Basic building block and smallest living component of an organism. |
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Term
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Definition
Also known as the plasma membrane, it is composed of lipids and proteins. (bilayer) Meaning it's not solid.
It is semipermeable, so things can move out and in based on needs. |
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Term
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Definition
-Highly selective filter that sheilds cell contents from the outside environment
-impermeable to most water-soluble
substances, including ions, glucose
and amino acids
(Glucose is only allowed in unless
insulin is attached.)
-permeable to lipid-soluble
substances, such as oxygen and
steroid hormones
(Oxygen is needed for the cell to
live and function.) |
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Term
| Functions of Cell Membrane |
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Definition
-Transports nutrients in and waste products out (because it is semipermeable)
-Cell recognition
-Communication with other cells
-Growth regulation
-Respond and adapt to changes in the environment (whether it's internal or external) Ex. Change in hot or cold |
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Term
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Definition
| Fluid-like substance within the cell |
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Term
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Definition
-Surrounds and protects the nucleus and organelles within the cell.
-Provides cushion-like protection |
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Term
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Definition
-The "brain" or the control center of the cell
-Carries most of the genetic material in the form of DNA |
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Term
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Definition
| -Major function is to protect and preserve the genetic information so it can be replicated exactly and passed on during cell division |
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Term
| Endoplasmic Reticulum (ER) |
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Definition
-Membrane component that extends throughout the cytoplasm
-A single continuous membrane, even though its curvy |
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Term
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Definition
| Main function is synthesis of membrane components, including LIPIDS and PROTEINS for the cell/plasma membrane and the other organelles or for other cells that need lipids and proteins |
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Term
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Definition
-Part of ER system
-Complexes of protein and RNA which are formed in the nucleus and trasported to the cytoplasm
-Primary funtion of ribosomes is synthesis of PROTEIN
-Depending on the destination of the protein to be created, ribosomes may bind to the ER or float free in the cytoplasm
-They are formed in the nucleus |
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Term
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Definition
-Rough ER has ribosomes attached
-Smooth ER does not have ribosomes attached |
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Term
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Definition
-Smooth ER is involved in lipid metabolism, where as Rough ER is involved in protein metabolism
-Most cells have very little smooth ER, however, structures specializing in production of steroid hormones or lipoproteins have significant amounts of smooth ER
Ex.-the liver manufactures lipoproteins so there would be a large amount of smooth ER present |
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Term
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Definition
| (liver cell) manufactures lipoproteins as well as detox of harmful lipid-soluble compounds such as alcohol, so there would be a large amount of smooth ER present |
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Term
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Definition
| -Composed of a stack of smooth compartments resembling a stack of hollow plates |
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Term
| Golgi Apparatus-continued |
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Definition
-Receives newly synthesized proteins and lipids by way of transport vesicles from the ER
-Transport vesicles diffuse into the GA and become part of the GA
-The proteins and lipids move through the middle to the last part...compartment (medial) to the final compartment where they depart for their final destination |
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Term
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Definition
-The way they are attached is based on where they are going
-As they pass through GAm the lipids or proteins attach to or rearrange sugar molecules, then packaged into Golgi transport vesicles (secretory vesicles)
-The way they are arranged/configured with sugar determines their destination, whether to the plasma membrane or lysosomes |
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Term
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Definition
-Bags of acidic digestive enzymes
-It is the cells's digestive system
-Breaking down occurs |
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Term
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Definition
-Acidification (break things down)
-Destruction of damaged and obsolete parts of cell (do not need)
-Ingestion of cell particles |
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Term
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Definition
-Final products of this digestion are simple molecules:
~AA and fatty acids which are used by the cell
~or cellular waste that is secreted at the cell surface
-Lysosomes are especially important in the liver (detoxify alcohol) and kidney (waste is excreted) |
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Term
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Definition
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Term
| Functions of Mitochondria |
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Definition
-Where energy comes from
-Convert energy to forms that can be used to drive cellular reactions
Cells with high energy needs such as cardiac and skeletal muscle, ave a high number of mitochondria
-Most energy comes from glucose, which is accompanied by insulin
-Oxygen is needed in cell to maintain life so it moves freely
-Cell needs energy, glucose needs insulin to get in,then in mitochondria converts to energy
-Number of mitochondria, depends on energy needs |
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Term
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Definition
-Whatever is going on with a person, is what is happening with the cells
-Disease and injury are cellular in nature
-Although pathologic processes present themselves in terms systemic effects and manifestations, ultimately it is the cells that make up the systems that are affected
-Even cancer is ultimately due to alterations in cell function |
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Term
| Cell Injury and Death-continued |
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Definition
| -Cells face many challenges to their survival but have efficient ways to cope with an altered cellular environment |
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Term
| Three ways cells respond to environmental change or injury |
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Definition
1. If the change is mild, or short lived, the cell may withstand the assault and completely return to normal (reversible cell injury) EX. Felt something hot, but take hand off right after
2. The cell may adapt to persistent but sublethal injury by changing its structure or function (generally reversible) EX. Kept hand on heat longer, so there is scaring.
3. Cell death may occur if the injury is too severe or prolonged |
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Term
| Cell death is irreversible and may be... |
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Definition
-Necrosis-cell death by external injury
-Apoptosis-pathologic process associated with significant tissure damage (programmed) |
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Term
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Definition
| -Occurs when cells shrink and reduce functions in response to a variety of normal and injurious factors |
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Term
| General causes of Atrophy |
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Definition
-Disuse-Immobilization by bedrest, casting of an extremity results in shrinkage. When resume activity, usually returns to normal size.
(not using..they will shrink!)
-Denervation-loss of nerve stimulation
Ex. Patient from accident in wheelchair, due to injury and loss of function/use |
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Term
| General causes of Atrophy-continued |
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Definition
-Ischemia-inadequate blood supply to the tissues. If present in lower extremities (poor circulation results in thin skin, muscle wasting and loss of hair)
-Tissues need oxygen! |
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Term
| General causes of Atrophy-continued 2 |
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Definition
-Nutrient starvation-whether due to poor intake, absorption, or distribution to the tissues
-Interruption of endocrine signals-gladular tissues such as the adrenal cortex, thyroid gland, and testicles depend on growth-stimulating signals to maintain size and functions
Loss of signals |
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Term
| General causes of Atrophy-continued 3 |
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Definition
-Persistent cell injury-chronic inflammation and infection, not used to fullest funtion
-Aging-Ex: bones |
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Term
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Definition
-Increase in cell mass accopanied by an augmented functional capacity. (Cells gets bigger, change in function whether its good or bad!)
-Cells hypertrophy is response to increased demands. Hypertrophy usually subsides when the demand has decreased or is removed, but not always. |
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Term
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Definition
-This type of adaptation usually occurs in cells that do not undergo mtotic division, such as differentiated muscle cells.
-Muscle build up with exercise(strength training)
Good or bad based on demands of the body. Ex. Not good for the heart to be enlarged, ok for muscles to be enlarged. Hard for heart to pump when enlarged. |
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Term
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Definition
-Cells that are capable of mitotic division can adapt by hyperplasia (increased number of cells)
-Usually results from increased physiologic demands or hormonal stimulation.
-Difference is if cells go through mitosis
Cells that go through mitosis get hyperplasia, and ones that don't get hypertrophy. |
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Term
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Definition
-Chronic irritation of epithelial cells may result in calluses and/or corns (chronic friction) overproduction of skin cells
-Estrogen can lead to an increase in endothelial and uterine stomal cells
EX: elevated number of RBCs in response to high altitude and liver enlargement in response to drug detoxification |
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Term
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Definition
-Replacement of one differentiated cell type with another (results from injury)
-Usually occurs with adaptation to persistent injury
-Fully reversible when agent causing the injury is removed
-Often involves replacement of glandular epithelium with squamous epthelium. Can occur with smoking, lung tissue will heal if one quits smoking! |
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Term
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Definition
-Disorganized appearance of cells (abnormal variations inn size, shape, and arrangement)
-Represents adaptation that has gone wrong. Usually has a greater potential to develop into cancer. EX: Keloid, overgrowth of skin, disorganized healing, and be a big scar or branding) |
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Term
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Definition
-Usually occurs as a result of ischemia or toxic injury and is characterized by:
-Cell rupture-whatever is inside the cell, is outside in a place where it should not be!
-Spilling of the contents into the extracellular fluid and blood-this triggers release of certain enzymes depending on the location of the cell death. Elevated amylase level indicates damage to pancrease and elevated creatine-MB or trophin level indicates cellular death in the heart.
-Inflammation |
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Term
| 4 types of tissue Necrosis |
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Definition
Depends on type tissue involved:
-coagulative-heart tissue, kidney
-liquefactive-brain
-fat-pancreas
-caseous-lung |
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Term
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Definition
-Cellular death involving a large area of tissue
-Usually results from interruption of major blood supply to a specific body part, such as toes, leg, or bowel |
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Term
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Definition
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Term
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Definition
A form of coagulative necrosis characterized by:
-Blackened, wrinkled tissue that is separated by adjacent healthy tissue by an obvious line of demarcation
-Usually occurs in the extremities
-Black tissue, and then right next to it is healthy tissue
-In patients with circulation problems, diabetes...
-No blood supply to area, so it dies. |
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Term
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Definition
-Liquefactive necrosis results is wet gangrene
-Typically found in internal organs
-Appears cold and black and may be foul smelling due to presence of bacteria
-Usually in tissues that have some circulation but surrounded by fluids |
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Term
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Definition
Rapid spread of tissue damage and release of toxins in the blood stream make this type of gangrene life threatening.
-Still have circulation, still has some alive tissue, smells really bad |
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