Week 4 Flashcards
sodium potassium pump
general info
Na+ ions are expelled
K+ ions brought in
Enzyme ATPase
what are the two types of active transport
primary + secondary
what is the process of primary active transport
carrier protein
Changes shape
Pumps the substance across the membrane
Energy to change shape of protein
Directly from ATP
Typical cell will expend 40% of its ATP energy on AT processes
Cyanide turns off production of ATP
what is active transport
Other substances hitch a ride
Secondary active transport proteins bind onto the Na+ as it leaks back into the cell across the plasma membrane
Thus use the potential energy
Stored in a concentration gradient
Indirect use of the ATP energy used in primary AT
what is a symporter
same direction
what is an antiporter
opposite direction
what is a vesicle
A structure within or outside a cell
Consists of liquid/cytoplasm
Enclosed by a lipid bilayer
what is endocytosis
Substances move in
Vesciles formed from the plasma membrane
exocytosis
Vesicle fuses with the plasma membrane
Material expelled out of the cell and into the extracellular fluid
what is a neutrophils
type of white blood cells
what are the organelles in the cell
centrosome
cilia & flagella
ribosomes
endoplasmic reticulum
strucute/function
cilia and flagella
Cell surface
Motile
Movement of foreign particles away from the cell, or fluid across its surface (cilia)
Cell movement (flagella) - sperm
structure/function
ribosome
Site of protein synthesis
Contain ribosomal RNA
structure/function
endoplasmic reticulum
Connected to the nuclear envelope
Extends into the cytosol
Rough ER – protein synthesis
Smooth ER – synthesis of steroids and fatty acids
when was the human genome project finished
1990-2003
what are the 4 basic types of tissues
Epithelial
Connective
Muscular
Nervous
structure/function
epithelial tissue
Allows body to interact with internal and external envrionment
Covers the body surface
Lines the hollow organs, body cavities and ducts
Forms the glands
strucutre/function
connective tissue
Supports and protects body and body organs
Stores energy reserves as fats
Provides immunity
structure/function
muscular tissue
Cells specialized to produce contraction and generation of force
Generates heat
structure/function
nervous tissue
Detects and responds to change both inside and outside the body
Creates electrical signals that activate muscular contraction of glandular secretions
what is a cell junction
Contact points between plasma membrane
types of cell junctions
tight junctions
adherens junctions
desmosomes
gap junctions
structure/function/examples
tight junctions
Strands of transmembrane proteins
Fuse together the outer surface of adjacent plasma membranes
Binds them together into leakproof sheets
Limit the leakage of various substances between the two cells
Epithelial cells lining the stomach, intestine and urinary tract
Inhibit passageof substances between cells
Prevent contents leaking into blood or surrounding tissue
structure/function/examples
adherens junctions
Dense protein plaque inside plasma membrane
Attaches to membrane proteins and cytoskeleton
Runs like a belt around the entire cell
Provides strong bond between the sides of adjacent epithelial cell membranes
Strong – Resists mechanical stress
structure/function/examples
gap junctions
Fluid-filled channels
Directly connects cytoplasm of two cells
Ions and small molecules diffuse from the cytosol of one cell to another
Prevent the passage of larger molecules
Also enable nerve impulses to spread rapidly amongst cells
In the eye
Used to transport nutrients and waste
Crystalline lens and cornea
structure/function/examples
Desmosomes
Attach one cell to another
Transmembrane glycoproteins extend into the intracellular space between adjacent cells
Each cell produces a similar plaque structure on its side of the junction
what is a hermidesmosome
attach a cell to the basement membrane below
what is a basement membrane
Thin membrane of protein fibres and mucopolysaccharies
Secreted by eepithelial cells
Non – cellular structure
Separates and anchors the epithelium from underlying tissue
what are the two laminae in the basement membrane
basal lamina
reticular lamina
what is the bowman’s layer
anterior part of corneal stroma
not a basement layer
structure + properties of
epithelial tissue
Continuous sheets
Single or multiple layers
Cells closely packed
Many cell junctions
Little intercellular space/fluid between
two main types of epithelial tissue
Covering, lining or surface epithelium
Glandular epithelium
what does avascular tissue mean
Rely on adjacent connective tissue for nutrients/waste disposal
what is the classification of cells
simple
Single cell layer
Functions: diffusion, osmosis and filtration
Secretion: mucus sweat and enzymes
Absorbtion: intake of fluids or ingested food in the intestine
what is the classification of cells
pseudostartified
Also simple
All cells lie on BM
Cells may not stretch to apical surface
Gives appearance of multi layers tissue
Also simple
what is the classification of cells
stratified
Two or more cell layers
Protection of underlying tissues
Location where significant wear and tear
what are the different shapes of tissue
squamous
cubodial
columnar
transitional
ciliated/non-ciliated
microvilli
keratinised
what is squamous tissue
flat rapid passage of substace
what is cubodial tissue
May have microvilli/cilia
Secretion and absorbtion
functions:
connective tissue
Binds, supports, strengthens
Protects, insulates, compartmentalises
e.g blood
extracellular matrix + cells
properties of
ground substance in extracellular matrix
Structure determines functional properties
Fluid, semi-fluid, gelatinous, or calcified
highly vascular except cartilage
nerve supply
what are the protein fibers of extracellular matrix
Secreted by connective tissue cells
Properties vary according to location
properties of collogen fibres
Strong, flexible, cushioning
E.g. bone, cartilage, tendons, ligaments
properties of elastic fibres
Protein elastin
Elasticity
E.g. Skin, blood vessel walls, lung tissue
what are the properties of reticular fibres
Collagen fibres coated in glycoprotein
Supporting framework of many soft organs e.g. spleen, lymph nodes
Form the basement membrane
what are the 3 types of connective tissue cells
mesenchymal stem cells
blasts cells
cyte cells
what are 3 examples of connective tissue cells
fibroblasts
macrophages
mast cells
leucocytes
what is collogen
insoluble fibrous protein
strong not stiff
what are the collogen strucutres in the eye
cornea-transparent tissue
sclera-opaque tissue
vitreous body
retina- typical thin basement membrane
choroid
what are membranes
tissue
e.g epithelial membrane with a epithelial layer + underlying connective tissue
what are the 4 principle membranes
Mucous
Serous
Cutaneous
Synovial
what do mucous membranes do
lie body cavities
open to exterior
what are serous membranes
line body cavities
not open to exterior
also covers organs
what does muscle tissue consist of
Muscle fibres: single elongated cells
Use ATP to generate force
what is the function of muscle tissue
Body movement
Maintain prosture
Generate heat
Generate hest
Protection
what are the types of muscular tissue
skeletal
smooth
cardiac
