Chapter 3 Compartmentation: Cells and Tissues単語カード | Quizlet

cranial

brain, spinal cord

thoracic

heart, lungs

An incision made between the ribs would be called a ____?

thoracotomy

An incision made through the sternum would be called a _____?

sternotomy

abdominopelvic

abdomen:

- lined with peritoneum which also surrounds the stomach, intestines, liver, pancreas, gallbladder, and spleen.)

Kidneys are retroperitoneal

Pelvis:

reproductive organs, urinary bladder and terminal portion of the large intestine

What is a lumen?

the interior of any hollow organ.

may be wholly or partially filled with air or fluid.

For some organs, the lumen is essentially an extension of the external environment, and material in the lumen is not truly part of the body's internal environment until it crosses the wall of the organ. True or false?

TRUE

Ex.

What are internal lumens?

lined with endothelium

ex. chambers of the heart

ex. blood vessels

What are external lumens?

lined with epithelium (have exit or entrance to body)

ex. air sacs of lungs

ex. digestive system, urinary, reproductive

What percent of the body is water?

60%

How much of body fluid is extracellular?

1/3 or 33%

fluid OUTSIDE of the cells

How much of body fluid is intracellular?

2/3 or 66%

fluid INSIDE of cells

What is the extracellular fluid divided into?

Plasma: (25% of the ECF) & contains more protein than interstitial fluid

Interstitial fluid: (75% of the ECF)

- surrounds cells of tissue, except the blood

each have nearly the same contents, expect for the proteins

How does fluid move among the compartments?

plasma <--> interstitium & extracellular <--> intracellular

What are the functions of the cell membrane (plasma membrane, plasmalemma)?

1. isolates cell (barrier)

2. regulates exchange (phospholipid bilayer, protein channels & transporters)

3. communication (receptors)

4. structure & support (anchor cytoskeleton)

Membrane phospholipids form bilayers, micelles, or liposomes.

How do they arrange themselves?

So that their nonpolar tails are not in contact with aqueous solutions such as ECF.

What is a phospholipid bilayer?

amphipathic

forms a sheet - external barriers

they are hydrophobic barriers

have a polar head (phosphate) and non-polar tail (fatty acids)

What is a micelle?

droplets of phospholipids.

important in lipid digestion

What is a liposome?

has an aqueous center

internal storage (phospholipid bilayer)

potentially the precursor to the first living cell

What does amphipathic mean?

has both hydrophilic and hydrophobic domains

What are the three main types of lipids that make up the cell membrane?

phospholipids

sphingolipids

cholesterol

What are phospholipids made of?

a glycerol backbone with two fatty acid chains extending to one side and a phosphate group extending to the other.

(major lipid of membranes usually)?

What are sphingolipids?

have fatty acid tails, but replaces phosphate with carbohydrate

they are slightly longer than phospholipids

What is cholesterol?

mostly hydrophobic

insert themselves between the hydrophilic heads of phosopholipids

helps make membranes impermeable to small water-soluble molecules and keeps the membrane flexible over a wide range of temperatures

What are integral proteins?

proteins that are embedded in the membrane

transmembrane - span across through the membrane (amphiphatic)

lipid-anchored - anchored into the bilayer on one side or the other (protein bound to fatty acid tail or sphingolipid)

What are peripheral proteins?

proteins on the surface of the membrane that include glycoproteins

can be removed without disrupting the membrane

Most membrane carbohydrates are sugars attached either to membrane proteins (glycoproteins) or to lipids (glycolipids). They are found exclusively where? what do they form there?

Found exclusively on the external surface of the cell, where they form a protective layer (THE GLYCOCALYX)

What does the cytoplasm consist of?

the fluid portion called cytosol;

insoluble particles called inclusions;

insoluble protein fibers; and

membrane bound structures called organelles

1. cytosol

2. inclusions

3. Insoluble protein fibers

4. organelles

Cytosol

intracellular fluid

semi-gelatinous fluid separated from the ECF by the cell membrane.

contains dissolved nutrients and proteins, ions, and waste products.

Inclusions

insoluble materials.

Some are stored nutrients, others are responsible for specific cell functions

i.e. glycogen, lipid droplets, ribosomes & polysomes

tend to clump together in clusters as storage areas of the cell

Cytoskeleton

compartmentalize in the cell

protein fibers and tubules

Organelles

membrane bound compartments that play specific roles in the overall function of the cell.

The inclusions of cells do not have boundary membranes and so are in direct contact with the cytosol. True or False.

TRUE

Does movement of material between inclusions and the cytosol require transport across a membrane?

NO

How are nutrients stored?

as glycogen granules and lipid droplets

What are ribosomes?

small dense granules of RNA and protein that make proteins under the direction of the cell's DNA

fixed and free

What are fixed ribosomes?

attach to the cytosolic surface of organelles, like the Rough ER

What are free ribosomes?

are suspended free in the cytosol...some form groups of 10-20 known as polyribosomes

If a ribosome is fixed, can it later become free and vice versa?

YES.

Where are ribosomes most numerous?

in cells that synthesize proteins for export out of the cell

What are microfilaments/actin fibers?

the thinnest cytoplasmic protein fiber.

function:

cytoskeleton; associates with myosin for muscle contraction

What are microtubules?

the largest protein fibers

hollow

made of tubulin

function; movement of cilia, flagella, and chromosomes; intracellular transport of organelles; cytoskeleton

What do microtubules form?

centrioles, cilia, flagella

What is the centrosome?

microtubule-organizing center

assembles tubulin molecules into microtubules

usually contains two centrioles

Where might you find cilia in the human body?

cells lining the upper airways and part of the female reproductive tract are covered with cilia.

Mitochondria

have an unusual double membrane

mitochondrial matrix is inside the inner membrane; contains enzymes, ribosomes, granules, and its own DNA.

intermembrane space, lies between the outer and inner mitochondrial membranes; plays an important role in ATP production

Endoplasmic Reticulum

a network of interconnected membrane tubes with three major functions

1. synthesis

2. storage

3. transport of biomolecules

rough and smooth

Rough ER

main site of protein synthesis

proteins are assembled on ribosomes attached to cytoplasmic surface of the RER, then inserted into the RER lumen, where they undergo chemical modification

Smooth ER

lacks attached ribosomes and is the main site for the synthesis of fatty acids, steroids, lipids

phospholipids for the cell membrane are produced here

can also detoxify in liver and kidney

stores calcium ions in skeletal muscles

Golgi Apparatus

consists of a series of hollow curved sacs (cisternae) stacked atop one another.

receives proteins made on the RER, modifies them and packages them into the vesicles

Nucleus

contains the DNA

has a nuclear envelope which is a two membrane structure that separates the nucleus from the cytoplasmic compartment.

has pores in which communication between the nucleus and cytosol takes place.

Protein synthesis

1. mRNA is transcribed from the genes in DNA

2. mRNA leaves the nucleus and attaches to cytosolic ribosomes, intiating protein synthesis

3. some proteins are released by free ribosomes into the cytosol or are targeted to specific organelles

4. ribosomes attached to the RER direct proteins destined for packaging into the lumen of the RER

5. Proteins are modified as they pass through the lumen of the ER

6. transport vesicles move the proteins from the ER to the golgi

7. golgi cisternae migrate toward the cell membrane

8. some vesicles bud off the cisternae and move in a retrograde

9. some vesicle bud off to form lysosomes or storage vesicles

10. other vesicles become secretory vesicles that release their contents outside of the cell.

How are cells in tissues held together?

cell junctions and other support structures

What is the extracellular matrix?

extracellular material that is synthesized and secreted by the cells of a tissue.

structures outside of cells or structures that allow cells to connect

always has two basic components: proteoglycans and insoluble protein fibers

What are proteoglycans?

glycoproteins which are covalently bound to polysaccharide chains

What insoluble protein fibers are included in the matrix?

like collagen, fibronectin, laminin

they provide strength and anchor cells to the matrix.

During growth and development, cells form cell-cell adhesions that may be transient or that may develop into more permanent cell junctions. True or false

true

What are cell adhesion molecules?

CAMs are membrane-spanning proteins responsible for both cell junctions and for transient cell adhesions.

mediate cell-cell or cell-matrix adhesions necessary for normal growth/development

What are the 3 major cell-cell junctions?

1. gap junctions

2. tight junctions

3. anchoring junctions

Gap junctions

simplest cell-cell junctions

all direct and rapid cell-cell communication through cytoplasmic bridges between adjoining cells.

connexins interlock to create passageways that are able to open or close

allow chemical and electrical signals to pass rapidly from cell-cell

Tight junctions

occluding junctions that restrict the movement of material between the cells they link.

cell membranes of adjacent cells partly fuse together with the help of claudins and occludins to make a barrier.

these create the blood-brain barrier

Desmosomes

attach to intermediate filaments of the cytoskeleton.

strongest cell-cell anchoring

important in the heart; keeps the cardiac cells together as they work together to pump

Epithelial tissue

lines all free body surfaces

- entering or exiting the body proper requires crossing epithelium

What are the functions of epithelial tissue?

protection, regulation, movement, secretion

Exchange epithelium

usually simple squamous

one layer of cells

flattened cell shape

features: pores between cells permit easy passage of molecules

permit rapid exchange of materials, like gases

found: in lungs, lining of blood vessels

Transporting epithelium

usually cuboidal or columnar

- apical membrane (against cavity) faces lumen

has microvilli that increase SA

-basolateral membrane (anchored) faces ECF, has folds to increase SA

one layer of cells

tight junctions prevent movement between cells; surface area increased by folding of cell membrane into fingerlike microvilli

found in intestine, kidney, some exocrine glands

selective about what can cross them

regulate the exchange of nongaseous materials like ions and nutrients between internal and external environments

Ciliated Epithelium

external movement: trachea moves mucus away from lungs from trachea up to larynx

columnar or cuboidal

one layer of cells

one side covered with cilia to move fluid across surface

found in: nose, trachea, upper airways; female reproductive tract

Protective Epithelium

many layers of cells; keratinized

flattened (squamous) in surface layers; polygonal in deeper layers

cells tightly connected by desmosomes

found in: skin and lining of cavities (like mouth) that open to the environment

Secretory epithelium

exocrine & endocrine

produces a lot of mucus, sometimes enzymes, hormones

one to many layers

columnar or polygonal

protein secreting cells filled with membrane bound secretory granules and extensive RER; steroid secreting cells contain lipid droplets and extensive SER

found in: exocrine glands (pancreas, sweat glands, salivary glands); endocrine glands (gonads, thyroid)

Structure of epithelia: basal lamina/basement membrane

thin layer of extracellular matrix lying between the epithelial cells and underlying tissues

composed of collagen and laminin filaments embedded in proteoglycans.

Leaky epithelia

anchoring junctions allow molecules to cross epithelium by passing through the gap between two adjacent epithelial cells. i.e. wall of capillaries

Tight epithelia

(in kidney)

adjacent cells are bound to each other by tight junctions that create a barrier, preventing substances from traveling cell-cell.

Types of epithelia

simple or stratified

squamous (flat)

cuboidal

columnar