Seminar 22: Tissues and organs Flashcards
(28 cards)
what are the 4 basic tissue types in animals
- connective tissue
- epithelial tissue
- nervous tissue
- muscle tissue
desc connective tissue, func, what it contains
- Contain cells in matrix of extracellular fibres
- provide structural support, transport nutrients & act as fat reservoirs
desc epithelial tissue, funcs & what it forms
- Cover external body parts, line internal body surfaces
- form diff glands
desc nervous tissue, what it contains & their func
- Neurons that respond to stimuli by generating electrical signals
- help coordinate body movements
desc func of muscle tissues & what they contain
- Specialised contractile cells
- these facilitate body movements
func of tight junctions
hold adj plasma membranes together, barrier to flow of molecules through intercellular spaces
func of anchoring junctions
form interconnected cytoskeletal network across cells, helps to resist mechanical forces
e.x of anchoring junctions (2)
- desmosomes
- adherens junctions
func of gap junctions
dispersed throughout plasma membrane (usually towards the basal end), act as communication channels b/w adj cells, allowing molecules & ions to pass through them
what is the extracellular matrix composed of?
interconnected network of fibres & ground substances
what is ground substance composed of?
mainly interstitial fluid (fills space b/w cells, connective tissue fibres & capillaries)
ECM makeup is based on ____ of ____ cells
SECRETION of LOCAL
neurons transmit ___ ___ AKA ___ ___
electrical signals = action potentials
func of glial cells
provide mechanical & nutritional support for neurons (don’t generate AP)
sarcomeres are composed of : (2)
thick myosin & thin actin filaments
sarcomeres are ___ ___ units in muscle fibre that allow …
REPEATING CONTRACTILE
MUSCLE CONTRACTION
muscle is composed of ___ of ___ ___ (cells)
BUNDLES of MUSCLE FIBRE
Muscle fibre contains…
multinucleate cells w/ many myofibrils
myofibrils are…
- larger structure of repeating sarcomere units
how does muscle contraction in skeletal muscles occur? (3)
- Myosin uses energy (ATP) to undergo movement that pulls actin filaments
- Results in them sliding past each other
- Due to arrangement of actin & myosin filaments, when contraction activated by AP, sarcomere shortens & muscle is CONTRACTED
what are the 3 layers of plant cell wall?
- middle lamella
- primary cell wall
- secondary cell wall
all have polysacc & proteins w/in them
organ systems are…
grp of organs that work together to carry out a certain func
desc the middle lamella (2)
- outermost cell wall layer
- b/w 2 adjacent cells, pectin allows the cells to adhere to one another & form tissues
desc the primary cell wall (2)
- b/w middle lamella & cell membrane
- thin & flexible to allow cell wall to expand during cell growth
