Week 2 Flashcards
what is the extracellular matrix and fluid?
extracellular matrix
- solid/gel form
- network of proteins/carbs
- provides structural support, anchors cells, regulates cell behaviour
extracellular fluid
- mainly water
- facilitates transport of nutrients/waste/signals
what is the cytoplasm and nucleus of a cell?
cytoplasm
- interior of a cell
- everything but the nucleus
nucleus
- stores DNA
- controls functions of a cell
what is the plasma membrane and what is it made of?
plasma membrane (shell)
- barrier, allows selective passage of materials
- made of phospholipid bilayer
- contains cholesterol and proteins:
-structural proteins
(connects cell to other
cells/ECM)
-channel proteins (hollow
pore for pH control thru
passage of H2O, Na, K
Ca, Cl)
-glycoproteins (cell
recognition, binding to
extracellular substances
- also contains glycocalyx (carb groups aid immune system- self/non-self identification)
what are the differences between active and passive transport?
passive transport
- does not require extra energy
- travelling with the concentration gradient
- involves diffusion
active transport
- requires energy (ATP)
- travelling against conc gradient
- sodium-potassium pump (sodium moved out, potassium moved in)
what is the cytoskeleton and its 3 components?
cytoskeleton- network of proteins that define cell shape and provides mechanical strength
microfilaments:
- thinnest
- found in most cells, especially muscle
- made of actin
intermediate filaments
- provides strength, resists deformation
- made of keratin
microtubules
- largest
- helps chromosome organisation during cell division
- made of tubulin
what are the purposes of microvilli, cilia, and centrioles?
microvilli- increase SA
cilia- move fluid/mucus across cell surface
centrioles- guide chromosomes during cell division
what is mitochondria and its functions in the cell?
- powerhouse (ATP production)
- smooth outer membrane, folded inner membrane (SA)
- cardiac muscle cells to meet energy demands, cells with low energy needs have less
what is the Golgi apparatus and its functions in the cell?
- modifies proteins into functional form
- packs cellular products into sacs (vesicles) which act as transport out of/within the cell (balances environment)
- membranous discs
what are ribosomes and their function in the cell?
- enzymes that make polypeptides
- small/large subunits made in nucleus then transported to cytoplasm
- exists both freely in cytoplasm and in rough ER
what is the rough/smooth endoplasmic reticulum and what are their functions?
rough ER
- has ribosomes (protein production)
- flattened/sheet-like chambers (cisternae)
- proteins are formed in the cisterni (polypeptides secreted in)
smooth ER
- no ribosomes
- involved in membrane production (replacement membranes), hormone production, and triglyceride production (in fat cells)
- produced steroid hormones in reproductive organs
what are the 4 categories of tissues?
epithelia tissue
connective tissue
muscle tissue
nervous tissue
what is epithelia tissue and what is its function in the body?
- creates barriers between different environments in the body
- includes epithelia (covering tissue) and glands (secrete chemicals)
- functions: protection, control of entering/exiting, sensory information, secretion
- all epithelia have apical (facing outside) and basal (facing deeper) surfaces
what are the types of epithelia tissue and their functions?
simple squamous epithelium (diffusion)
- gas exchange in lung alveoli, endothelium of blood vessels/heart
simple cuboidal (secretion/ absorption)
- kidney tubules, secretory glands
stratified squamous (chemical/mechanical protection)
- skin, mouth, anus, rectum
stratified cuboidal
- sweat glands
stratified columnar
- pancreas ducts
transitional epithelium (stratified)
- found in stretchable organs
- e.g. bladder (when empty, apical layer is cuboidal. as filled, apical layer becomes more squamous)
what is connective tissue, its function, and its four types?
- structural support, connects body parts, protects internal organs and maintains their shape, provides framework for muscle movement
- contains cells and extracellular matrix, extracellular fibres determine mechanical properties (collagen- strength, reticular- framework, elastic)
- major classes: connective tissue proper, cartilage, bone, blood
what is lose connective tissue and its three types?
more cells, ECM interwoven with fibres
areolar connective tissue
- gel-like ECM that retains water
- found beneath epithelial tissues
- support, strength, elasticity
- contains all 3 fibres
- houses many cells involved in inflammation/immune system response
reticular connective tissue
- provides framework for blood-forming cells, immune defences
- found in lymph nodes, spleen, bone marrow
- contains reticular fibres
adipose tissue
- mainly fat cells, minimal ECM
- metabolic fuel reservoir, thermal insulation, organ cushioning
what is dense connective tissue and its three types?
less cells, ECM mainly fibres
regular dense connective tissue
- parallel collagen fibres
- found in tendons, ligaments
- great strength along fibre direction
irregular dense connective tissue
- random collagen fibres
- resists stretching from different directions
- found in dermis (deeper layer of skin), fibrous capsules surrounding joints
dense elastic connective tissue
- abundant elastic fibres in ECM
- found in airway walls, arteries
what is cartilage and its function?
- part of the skeleton between bones
- provides support, flexibility, minimises friction
- chondroblasts secrete ECM of cartilage
- ECM contains collagen fibres and proteoglycan molecules
- high water content contributes to its resistance to compression/low friction
what are the three types of cartilage and their functions?
hyaline cartilage
- forms smooth covering on ends of long bones
- found in ribs, nose, trachea, larynx
elastic cartilage
- contains more elastic fibres
- found in external ear, epiglottis
fibrocartilage
- contains more collagen fibres
- found in intervertebral discs, knee menisci
what is bone (osseous tissue) and its functions?
- protects organs, structural support
- provides rigid framework for muscle attachment
- osteoblasts produce ECM of bone
- ECM contains collagen fibres for strength, calcium salts for hardness
what is muscle tissue and its function, and list the three types
- cells capable of contracting/relaxing
- allows movement, generates force, coordinated motion
uses actin and myosin proteins to generate force and uses ATP for energy - skeletal, cardiac, smooth
what are the differences between the three types of muscle tissue?
skeletal muscle
- pulls on bones for movement
- long thing cells with multiple nuclei
- striated
cardiac muscle
- found in the heart
- shorter cells with high mitochondria for continuous ATP generation
- striated
smooth muscle
- in walls of hollow organs (blood vessels, airways, bladder, uterus)
- no striations
what is nervous tissue and its function within the body?
- specialised cells (neurons) which transmit electrical signals
- allows communication and coordination within the body
- concentrated in the brain and spinal cord (CNS) and extends through the body (peripheral nervous system)
- PNS has motor commands for muscles/glands and receives sensory signals from ears, eyes, skin
- includes glial (supporting) cells and neutrons (generates/transmits/receives electrical signals)
