Chapter 2 Flashcards
Cytoskeleton function
- forms fibres necessary for shape and stability of cells
- organelles are held in place by the cytoskeleton and it controls movement of organelle
Three componetd
= - microfilaments
- contractile fibres from actin protein
- responsible for cell movement and cell contraction during cytokinesis
Microtubules
Intermediate fibres
Microtubules
- Globular tublin proteins polymerise to fork tubes thst are used to form a scaffold like structure thst DETERMINES SHAPE OF CELL
- also act AS TRACTS FOR MOVEMENT of organelles like vesicles
Spindle fibres are made from theee
Intermediate fibres
Give mechanical strength to cell and help maintain integrity
Cytoskeleton summary
Intermediary fibres
- contractile proteins made from actin allow whole cell MOVEMENT, also help contraction twke place in mitosis
Microtubules
- these globular Tubulidentata proteins that POLYMERISE to form scaffold like structured thst determine the shape of the cell
- also act as tracks for movement if organelles around the cell, including vesicles (like lysosomes which are just vesicles with hydrolytic ensymes with three functions, apoptosis, phagocytosis help, and also digesting old material)
Intermediate fibres- give mechanical strength snd integrity ti cell
What are centrioles , centrosome, what made from ?
They are part of cytoskeleton made from MICROTUBULES
Two combined is the CENTROSOME
This is duplicated in mitosis and helps form SPINDLE FIBRE for the process and organisation, in where microtubules attack from the centrosome to the chromosome plste
Centrioles found everywhere?
What other function dintheybhave ?
Not in most fungi snd plants
If orgsnism has flagella or Cillia , it is thought to help position these “
Flagella
Flagella enable movement = motility p
- in some cells used as a sensory organelle detecting chemical changes in cells environment
These are whipmlike
Cillia + two typed ?
Can be stationary or bobble
Stationary
- present on surface of many cells and have an importsnt function in sensory organs such as the NOSE
Mobile Cillia
This one is the one that caused MOVEMENT
- they best in rhythmic fsdhiojneuoduncresred s current snd causes objected adjacent to cell to love, for example in cilalted tissue which causes mucus to move down to digestive system in trachea
Structure if cilla and flagella
What drtcutuee does this
9+ 2 arrangements
This was two central mictruhuoed which are black surrounded by 9 pairs of mictroibuled like a wheel
Again 9mpaird of microtubules in a ring surrounding two microtubules in the middle
What organelles involved in proteins yt he Neids ?
This happens in the ribosomes and starts in nucleus / as dna is trsncfibedto RNA and escape via nuclesrporem
Involves ribosomes firsts, endoplasmic reticulum more, Golgi apparatus etc
Endoplasmic reticulum, whst is ti snd what is difference between rough and smooth
Thenisna network of membranes enclosed in flattened sacs called cisternae
Connected to outer nucleus l-YDRSTE PRODUCTION AND STORSGEN
- rough cintaijdnRIBSOKED (so kinda rough) m responsible for sythesis and transport of proteins
Thstsit, smooth lipid and carbohydrate , rough proteins and trandorotif em
-smooth is the SITE FOR LIPID SND CSRBOH
What do secretory cells have more than as a result
Need to release more ensymes or hirmones, so need more ROUGH ER so. Ore proteins cna be produced and transported
Ribosomes?
Site of protein synthesis , either floating or attached to reticulum to make rough p
- they DONT HAVE MEMBRANE
- made from RNA molecules made in NUCLEOLUS (which is site, does this by combine rRNA with proteins to make ribsokedm, and RNA produces rRNA)
Mitochondria sjdnchlorolsdtshave own ribosomes and dna , and double membrwne = endisymbitouc
Golgi apparatus?
How structure similar
- what type of vesicles does it mske
What is cis and trans face and where
Simialr to smooth ER AS IT HAS mambrsnius sscs in closed cslled cisternse , does nit have ribosomes
- function of modifying oroteind by giving carbon chains, snd PACKAGAING THRM INTO VESICSKED SO THEY CSN BE TRSNSORTED
- these could be secretory vesicles, to leave the cell by exocytosis
-or vesicles to be kept in the cell as lysomes which special
They enter from cis FACE, and exit from trans face
Theee make them secretory vesicles, whereas rer makes them. Transport vesicles to the cis fsce