Physio Exam 1

Cells are the basic structural
and functional units of life. 50-100 trillion in the human body.

the outer thin and flexible membrane of the cell which separates the intracellular from extracellular compartment (fluid)

plasma membrane
cytoplasm
nucleus

Plasmolemma
Fluid Mosaic Model

double layer of lipids embedded with proteins

phospholipids, cholesterol + glycolipids

Phospholipids

hydrophilic, polar, main constituent of intra + extra cellular fluid, and lie along the inner + outer surface of membrane

hydrophobic, lipidphillic + nonpolar, line up in center of membrane

integral and peripheral

most extend entirely through the membrane (transmembrane) but some protrude from one side of the membrane. Could act as receptors

Integral

receptors

cytoplasmic

support the cytoplasmic side of
the membrane by a network of filaments

Sugar covering or cell coast that is a short chain of carbohydrate projected out from the external surface of glycoproteins or glycolipids

cell-to-cell binding and
recognition

-An external barrier against outside forces
-external proteins act as receptors (for hormones + neurotransmitters) in cell-cell recognition
-transport of substances in and out of the cells

selectively permeable plasmolemma only allows small nonpolar, and some small polar things into cell
Larger molecules are blocked, and some may be able to go through protein transport

down the concentration gradient
no ATP needed

small, uncharged molecules like oxygen, Co2 and fat soluble molecules across the membrane

low to high concentration movement
ATP needed

most larger water-soluble or charged
molecules, such as glucose, amino acids and ions are transported
by a pump or carrier and involve the integral proteins

Vesicularulk transport

endocytosis and exocytosis

membrane lined cytoplasmic vesicles fuse with the plasma membrane and release their contents to the outside of the cell. (ex. mucus and protein secretions from the glands of the body)

brings large molecules into the cell, through an initial infolding part of the plasma membrane that encloses them to form cytoplasmic vesicles

vSNAREs and tSNAREs

Proteins extending from the vesicle
membrane vSNAREs, bind with plasma
membrane proteins, the tSNAREs (t for
target), this causes the lipid layers of
the vesicle and cell membrane to join
together.

Clathrin protein, found on cytoplasmic side

phagocytosis
pinocytosis
receptor-mediated endocytosis

cell eating

cell drinking, fluid phase endocytosis

Pseudopodes from the plasmolemma which engulfs cell debris

phagosomes fuse to lysosomes for enzymatic break down of the phagosomal contents.
What other important cells have phagocytic activity?

White blood cells

a small infolding of the plasma membrane surrounds a small quantity of extracellular fluid containing dissolved molecules.

nutrient absorption from outside the cell.

lining of the small intestine

selective mechanism for specific molecules are brought into the cells by first attaching to a receptor on the membrane before being taken into the cells in a protein coated vesicle

Insulin, other hormones, enzymes, low desity lipoproteins (LDL)

molecules that carry cholesterol in the blood to the body's cells

Contents of the vesicles are released by binding to lysosomes and the
receptors are recycled back to plasma membrane

Receptor mediated endocytosis

inherited disease in which the cells lack the receptors that bind to
cholesterol binding LDLs

cholesterol cannot enter the cells and builds up in the blood,
causing hypercholesterolemia and atherosclerosis which lead to stroke or
myocardial infarction

cellular region between the nucleus and plasma membrane

cytosol, or cytoplasmic matrix which is a viscous fluid containing water, ions and enzymes, inclusions containing stored nutrients and pigments and organelles.

viscous fluid containing water,
ions and enzymes, inclusions containing stored nutrients and pigments

dark staining granules with no membrane. amino acids link together to form protein

proteins and rRNA

Ribosomes

make protein used in cytosol

make proteins used to cell membrane or exported out of the cell

mRNA is read by rRNA of the ribosome to find the correct amino acid to link in a chain of amino acids. The tRNA carries the specific AA coded for to the rRNA to be put into the sequence. dictated by dna of the nucleus.

a ribosome-studded system of membrane-walled envelopes in cytosol, called cisternae

to rER cisternae and then are secreted by the cell in vesicles

Ribosomes

No ribosomes attached
membranous system of sacs and tubules in the cytosol

synthesis of lipids and steroids,
lipid metabolism and drug detoxification

stack of 3-10 disc-shaped envelopes or cisternae which are bound by membrane. cisternae have cis (convex) and a trans (concave) face

sorts the products of rER and packs them in membrane bound vesicles and sends
them to their proper destination.
Also produces secretory granules and lysosomes

rod like organelles covered by 2 membranes in the cytoplasm. The inner like membrane is folded into projections called cristae. Main site of ATP synthesis

-spherical, membrane-walled sacs containing digestive enzymes called Acid hydrolases.
-site of intracellular digestion and digest deteriorated organelles and substances brought into the cells by vesicles.
-fuse with phagosomes and empty their enzymes into phagosomes

Lysosomes

mental retardation,
blindness, spastic movements and death
within 1.5 years from birth.

an inherited disease in which infants lack specific enzymes in the lysosomes responsible for break down of certain glycolipids

glycolipids accumulate in the cell membrane specially on neurons

lack of the glucocerebrosidase enzyme causes harmful substances to build up in the liver, spleen, bones, and bone marrow. The substances prevent cells and organs from working properly.

3

-Most common
-Involves bone disease, anemia, and enlarged spleen, and thrombocytopenia.
-Affects both children and adults

-usually begins in infancy with severe neurologic involvement.
-This form can lead to rapid, early death.

may cause liver, spleen, and brain problems. Patients may live into adulthood.

Varies with type:
-Bone pain and fractures
-Enlarged spleen
-Enlarged liver Lung disease
-Seizures

membrane walled enzyme containing sacs

contain oxidase and catalase enzymes

use oxygen to neutralize aggressively reactive substances (free radicals) and they convert them to hydrogen peroxide,which will then be converted to O2 and H2O

catalases, which break down poisons like alcohol, phenol, and formaldehydes that have entered the body

Kidney and Liver

network of rods throughout the cytosol that work to support structure and movements of the cell

microtubules, microfilaments, intermediate filaments

-cylindrical structures made of tubulin proteins
-radiate out from the centrosome region close to the nucleus
-gives cell shape
-organize the distribution and transport of various organelles within the cytoplasm

-fine filaments of contractile protein actin
-are labile
-actin + mysosin = contractile force for movement
-muscle contraction
-amoeboid movements and pseudopod extension

tough, insoluble, stable protein fibers
resist tension on cell

spherical structure in the
cytoplasm near the nucleus. It consists of
an outer cloud of protein called: matrix
and an inner pair of centrioles
Matrix protein is involved in the elongation
of microtubules and mitotic spindle of
microtubules radiates from it in dividing
cells.

Impermanent structures in the cytoplasm
such as lipid droplets and glycogen
containing glycosomes.

-in the core of centrosome.
-These are paired cylindrical bodies
perpendicular to one another and each
composed of nine triplets of microtubules.
-They organize a microtubule network
during mitosis to form the spindle and asters. They also form the bases of cilia
and flagella

The control center of the cell and contains DNA which directs the cell's activities by providing instructions for protein synthesis

red blood cells, Anucleated

multiple nuclei

-Nuclear Envelope
-Chromatin and Chromosomes
-Nucleoli

surrounds the nucleus and has pores and is continuous with endoplasmic reticulum

-dark staining body within the nucleus
-contains part of chromosomes and is cell's ribosome producing machine (has genes that code for rRNA)

transcription

granular thread-like material in nucleus composed of DNA and histone proteins, folded compactly and creates chromosome with an X shape

Double helix chains of nucleotides that pair

A=T
G=-C

wraps around clusters of 8 spherical proteins called histones, which regulate gene expression and transcription

our traits

cluster of DNA and histone

Single long chain of DNA tightly wound.

46
44 are somatic
2 are sex

is distributed in chromosomes.During cell division, the chromatin is highly coiled, making the chromosomes appear as thick rods.

1 interphase - cell growth
2 mitotic phase - leads to cell division into 2 cells (essential for growth and repair of body)

G1 - cells active and grow vigorously and centrioles replicate
S - DNA replicates itself for the future 2 daughter cells having identical genetic material
G2 - enzymes needed for cell division are synthesized, centrioles finish replication and cell gets ready to divide

PMAT

-Asters (stars) form
-Chroms formed from coiling and condensation of chromatin threads (2 chromatins are identical, held together by centromere and protein complex called cohesin)
-nucleoli disappear, centriole pair separates, nuclear envelope fragments
- microtubules disassemble and assemble to form mitotic spindles which lengthen and push centrioles to poles of cell

-Chromosomes line up in the middle to form metaphase plate
-separase, which cleaves cohesin, start to separate chromatids

-V shaped chromatids are pulled apart at centromere kinetochore spindles to become chromosomes of daughter cells
-other spindles push against each other to elongate cell
short phase (few mins)

-prophase in reverse
-chromosomes at opposite ends of cell uncoil and resume extension of chromatin
-nuclear envelope forms by rER
-nucleoili

separates the 2 nuclei in the cell that forms for a short period

-special division of gametes
-2 steps meiosis 1 &2
-2 divisions resulting in 4 haploid cells (gametes) each containing 23 chromosomes and half the amount of DNA (1N) found in normal somatic cells (46 chromo and 2N)

Synapsis: pairing of 46 homologous duplicated chromosomes.

*Crossing over: large segments of DNA are exchanged.

Alignment: 46 homologous duplicated chromosomes align at the metaphase plate.

Disjunction: 46 homologous duplicated chromosomes separate from each other; centromeres do not split.

Cell division: two secondary gametocytes (23 duplicated chromosomes, 2N) are formed.

Synapsis: absent

Crossing over: absent

Alignment: 23 duplicated chromosomes align at the metaphase plate.

Disjunction: 23 duplicated chromosomes separate to form 23 single chromosomes; centromeres split.

Cell division: four gametes (23 single chromosomes, 1N) are found.

Abnormal number of chromosomes. (Ex trisomy, monosomy)

Trisomy 21 and some cases affects chromosome 14 too

XXY
exhibits both genitals

XO female
sterile

-23 single chromosomes (22 autosomes and 1 sex chromosome)
-Haploid= a cell containing 23 single chromosomes
-female gametes contain only X sex chromo
-male gametes contain either X or Y chromo; therefore, the male gamete determines genetic sex of the individual

200

complex and may involve cell damage due to free radicals as a result of normal cell metabolism or cell injury due to radiation and chemical pollutants.

a decrease of energy production by
radical-damaged mitochondria which weakens and ages the cell

vitamins C +E, slows aging

slows aging by lowering metabolic rate

senescence,
Propose aging is programmed into our genes

the method whereby cells are removed from tissues in an orderly fashion as a part of normal maintenance or during development. (programmed cell death)

-chromatin condensation
-nucleus break up
-plasma membrane break up
-cells shrink to membrane enclosed bodies apoptotic bodies

Certain cytokines, such as tumor necrosis factor (TNF), may also activate caspases that degrade regulatory and structural proteins in the nucleus and cytoplasm, leading to the morphological changes characteristic of apoptosis

too much apoptosis -> extensive nerve cell loss, alzheimers disease + stroke

Too little apoptosis -> linked to cancer and other autoimmune disease

When cell multiplies and divides rapidly and abnormally
either malignant or benign

-local mas remains compacted and encapsulated
grows slowly
-seldom kills host

-not capsulated, grows rapidly, cells are immature and invade surrounding tissue
-Metastasis

invading other tissues by means of lymphatic or blood tissue

result of mutations of certain regulatory genes, called protooncogenes, which normally stimulate or inhibit cell proliferation and development

bladder cancer and Myelogenous Luekemia

genetic accidents or viruses

Oncogenes dominate the normal alleles (proto-oncogenes), causing deregulation of cell division, which leads to a cancerous state.

bladder cancer and acute myelogenous leukemia

epithelial, connective, muscle, nervous

Groups of tissues that work together to perform a specific function or related functions
Groupings of these four primary tissues into anatomical and functional units

contractile tissue derived from mesodermal layer of embryonic germ cells.

to produce force and cause motion, either locomotion or movement within internal organs

skeletal, cardiac, smooth

-Striated
-attached to skeleton
-creates movement by applying force to bones and joints via contraction

-within walls of organs and structures
-not under conscious control

esophagus, stomach, intestines, bronchi, uterus, urethra, bladder, and blood vessels

-Special kind only found in heart
-The muscle in the body with the most mitochondria
-involuntary

reacts to stimuli and conducts various impulses in organs to react to the stimulus

-branches throughout the body made up of specialized cell called neurons
-found in brain, spinal cord, and peripheral nerves

easily stimulated and transmit impulses very rapidly.

Epinuerium

made up of many nuerons (nerve cell fibers)

surrounds bundle of nerve fibers

thin layer of loose connective tissue, surrounds the individual nerve fibers

1. Protection: Epithelial cells from the skin protect underlying tissue from mechanical injury, harmful chemicals, invading bacteria and from excessive loss of water.


2. Sensation Sensory stimuli: penetrate specialized epithelial cells. Specialized epithelial tissue containing sensory nerve endings is found in the skin, eyes, ears, nose and on the tongue.


3. Secretion In glands:, epithelial tissue is specialized to secrete specific chemical substances such as enzymes, hormones.

4. Absorption: Certain epithelial cells lining the small intestine absorb nutrients from the digestion of food.
5.Excretion: Epithelial tissues in the kidney excrete waste products from the body and reabsorb needed materials from the urine. Sweat is also excreted from the body by epithelial cells in the sweat glands.


6. Diffusion: Simple epithelium promotes the diffusion of gases, liquids and nutrients. Because they form such a thin lining, they are ideal for the diffusion of gases (eg. walls of capillaries and lungs).


7. Cleaning: Ciliated epithelium assists in removing dust particles and foreign bodies which have entered the air passages.


8. Reduces Friction: The smooth, tightly-interlocking, epithelial cells that line the entire circulatory system reduce friction between the blood and the walls of the blood vessels.

sheets of cells that cover body surfaces and cavities

Their function is to protect the body
(such as the skin) or sensory reception such as the olfactory epithelial cells, absorption, such as the internal covering cells of the intestine, ion transport and filtration, like the cells covering various tubules in the kidney.

Squamous (flat) x Cuboidal (cubelike) x Columnar (tall and rod like)
Simple (1 layer) x Stratified (multiple)

-multiple layers
-The superficial layer is used to classify the layer. Only one layer touches the basal lamina. Stratified cells can usually withstand large amounts of stress

-only one layer of cells but looks stratified bc position of nuclei
-mainly used in only pseudostratified columnar epithelium

-squamous cells all of which touch basement membrane
-irregularly shaped and very flat, cell nucleus bump
-Gases and other substances can easily diffuse across squamous cells to the underlying basement membrane, and because of their smooth surface, liquids can quickly flow over them
-lining body cavities and capillaries to reduce friction, as well as lining the alveoli to facilitate gas exchange

-Single layer of cubelike cells with large, spherical central nuclei.

-Function: secretion and absorption.

-Location: Cuboidal epithelium is found in glands and in the lining of the kidney tubules as well as in the ducts of the glands. They also constitute the germinal epithelium which produces the egg cells in the female ovary and the sperm cells in the male testes

-one or more layers. The cells are elongated and column-shaped. The nuclei are elongated and are usually located near the base of the cells.

-Location:
Columnar epithelium forms the lining of the stomach and intestines. Some columnar cells are specialized for sensory reception such as in the nose, ears and the taste buds of the tongue. Goblet cells (unicellular glands) are found between the columnar epithelial cells of the duodenum.

-Function:
They secrete mucus or slime, a lubricating substance which keeps the surface smooth.

Function: Secretion, mucus.

Location: Ducts of large glands, Ciliated variety lines the trachea, most upper respiratory tract.

are multi-layered.
They protect areas such as ducts of sweat glands and the male urethra.

Function: Protection

Are several cell layers.

Function: Protection, secretion

Location: small amount in male urethra and in large ducts of some glands.

vagina

-Description: resembles both stratified squamous and stratified cuboidal; basal cells cuboidal or columnar, surface cells dome shaped or squamous like, depending on degree of organ stretch
-Function: Stretches readily, permits stored urine to distend urinary organ
-Location: lines the ureters, bladder, and part of the urethra

exocrine or endocrine
each produces various products

-products of these cells collect in the duct of the gland and flow toward the surface to which the duct is in contact
-Multicellular exocrine glands are classified by the structure of their ducts as
simple, or compound and by the structure of their secretory units as tubular,
alveolar (acinar), or tubuloalveolar
-retain ducts to body surfaces
-goblet cells are examples of mucus secreting unicellular exocrine glands

-"ductless"
-product is released across the cell membrane into interstitial spaces around the cells. Diffusion of the product into capillaries follows

-the pancreas which has an endocrine as well as
exocrine parts. The endocrine part produces insulin and glucagon
and other hormones. The exocrine part secretes enzymes responsible
for food breakdown and digestion.

merocrine, apocrine, holocrine

How most glands release prods
form membrane-bound secretory vesicles internal to the cell. These are moved to the apical surface where the vesicles coalesce with the membrane on the apical surface to release the product

apical portions of cells are pinched off and lost during the secretory process. This results in a secretory product that contains a variety of molecular components including those of the membrane.

mammary glands

-involves death of cell
-The secretory cell is released and as it breaks apart, the contents of the cell become the secretory product
most complex products released here

Some sweat glands located in the axillae, pubic areas, and around the areoli of the breasts release their products in this manner. Sebaceous glands also are of this type

1- Adhesion proteins link plasma membranes of adjacent cells
2- Contours of adjacent cell membranes
3- Special cell junctions:
-Tight junctions
-Adhering junction
-Desmosomes
- Gap junctions

a type of junctional complex.They are formed by claudin and occludin proteins, joining the cytoskeletons of the adjacent cells.

-hold cells together
-block the movement of integral membrane proteins between the apical and basolateral surfaces of the cell
-aims to preserve the transcellular transport
-prevent the passage of molecules and ions through the space between cells

1. two disc like plaques connected across intercellular space
2. plaques adjoining cells are joined by proteins called cadherins
3. proteins interdigitate (lock) into extracellular space
4. intermediate filaments insert into plaques from cytoplasmic side

1- passageway between two adjacent cells
2- they let small molecules move directly between neighboring cells
3- cells are connected by hollow cylinders of protein

1- Epithelial cells lie on a protein sheet called basal lamina.
2- It acts as a filter and base on which regenerating epithelial cells can grow.
3- The basal lamina and some underlying reticular fibers , form the ticker basement membrane.

-"connecting" function. It supports and binds other tissues
-cells scattered throughout extracellular matrix
-derived form mesoderm

-Collagenous Fibers
-Elastic fibers
-Reticular Fibers
Fibrous Connective Tissue

-Adipose
-Cartilage
-Bone

-autosomal dominant genetic disorder of the connective tissue
-disproportionately long limbs, long fingers, tall, cardiovascular abnormalities (especially those affecting heart valves and aorta)

-defect in the gene on chromosome 15 which encodes a glycoprotein called fibrillin-1
-Fibrillin is essential for the formation of the elastic fibers found in connective tissue

group of rare genetic disorders affecting humans and domestic animals caused by a defect in collagen synthesis (Collagen I and III)

67% intracellular

33%

cardiovascular system where it makes up fluid portion of blood

environment fluids, as interstitial, or tissue, fluid, within a matrix of glycoproteins and proteoglycans. It consists of the protein fibers collagen and elastin. This fluid, derived from blood plasma, provides nutrients and regulatory molecules to the cells. The extracellular environment is supported by collagen and elastin protein fibers, which also from the basal lamina below epithelial membranes

-class of glycoproteins that extend from the cytoskeleton within a cell, through its plasma membrane, and into the extracellular matrix
- by binding to components in matrix serve as Adhesion molecule between cells and extracellular matrix

1. requires action of specific carrier proteins in membrane called carrier mediated transport
2. transport through the membrane thats not carrie mediated. Involves the simple diffusion of ions, lipid-soluble molecules, and water through the membrane.

net diffusion of solvent (water) through a membrane

simple diffusion, osmosis, and facilitated diffusion.

-is the only form of transport that is not carrier-mediated.
-occurs down and electrochemical gradient (downhill)
-does not require metabolic energy and therefore is passive

-high oil/water partition coefficient of the solute increases solubility in the lipid of the membrane.
-decrease radius (size) of the solute increases the speed of diffusion.
-decrease membrane thickness decreases the diffusion distance.

small hydrophobic solutes

through water-filled channels, or pores. If the solute is an ion, then its flux will depend on both the concentration difference and the potential difference across the membrane

-The characteristics of carrier-mediated transport apply to facilitated diffusion and primary and secondary active transport.
1. Stereospecificity. For example, D-glucose (the natural isomer) is transported by facilitated diffusion, but the L-glucose isomer is not. Simple diffusion, however, would not distinguish between the two isomers because it does not involve a carrier.
2. Saturation. The transport rate increases as the concentration of the solute increases, until the carriers are saturated. The transport maximum (™) is analogous to the maximum velocity (V max) in enzyme kinetics.
3. Competition. Structurally related solutes compete for transport sites on carrier molecules. For example, galactose is a competitive inhibitor of glucose transport in the small intestine.

-occurs down and electrochemical gradient (downhill), similar to simple diffusion.
-does not require metabolic energy and therefore is passive.
-is more rapid than simple diffusion.
-is carrier-mediated and therefore exhibits stereospecificity, saturation, and competition.

-glucose transport in muscle and adipose cells in downhill is carrier-mediated, and is inhibited by sugars such as galactose, therefore, it is categorized as facilitated diffusion. In diabetes mellitus, glucose uptake by muscle and adipose cells is impaired because the carriers for facilitated diffusion of glucose require insulin.

-occurs against an electrochemical gradient (uphill)
.-requires direct input of metabolic energy in the form of adenosine triphosphate (ATP) and therefore is active.
-is carrier-mediated and therefore exhibits stereospecificity, saturation, and competition.

s a number between zero and one that describes the ease with which a solute permeates a membrane.
If the RC is one, the solute is *impermeable. Therefore, it is retained in the original solution, it creates an osmotic pressure, and it causes water flow. Serum albumin (a large solute) has a reflection coefficient of nearly one.
b. If RC is zero, the solute is completely permeable. Therefore, it will not exert any osmotic effect, and it will not cause water flow. Urea (a small solute) has a reflection coefficient of close to zero and it is, therefore, an ineffective osmole.

a. The transport of two or more solutes is coupled.
b. One of the solutes (usually Na+) is transported downhill and provides energy for the uphill transport of the other solute(s).
c. Metabolic energy is not provided directly, but indirectly from the Na+ gradient that is maintained across cell membranes. Thus, inhibition of Na+, K+-ATPase will decrease transport of Na+ out of the cell, decrease the transmembrane Na+ gradient, and eventually inhibit secondary active transport.
d. If the solutes move in the same direction across the cell membrane, it is called cotransport, or symport.
e. in the solutes move in opposite directions across the cell membranes, it is called countertransport, exchange, or antiport

-is the concentration of osmotically active particles in a solution.
-is a colligative property can be measured by freezing point depression.
-can be calculated using the following equation: Osmolarity= g x c

aka oncotic pressure. The osmotic pressure created by proteins (plasma proteins)