2.1 Cell Structure Flashcards
1
Q
nucleus
A
- surrounded by nuclear envelope
- some regions of outer and inner nuclear membranes fuse for dissolved substances, ribosomes to pass
- has pores for larger substances( mRNA, hormones, to pass
- has chromosome
- ## has nucleolus, make ribosome
2
Q
nucleus in sum
A
- control centre of cell
- stores organism genome
- transmits genetic info
- provides instruction for protein synthesis
3
Q
RER
A
- system of membranes
- contains fluid-filled cavities(cisternae), contin. w/ nuclear membrane
- ribosomes on SA
- intracellular transport system
- cisternae form channels for transporting substances from one are of cell
- provides large sa for ribosomes
- –> assembles amino acid -> proteins
- -> protein actively pass thr membrane into cisternae and are transported to golgi body
4
Q
SER
A
- system of membranes
- contains fluid-filled cavities(cisternae), contin. w/ nuclear membrane
- no ribosome
- has enzymes for lipid metabolism
synthesis of cholesterol
lipids/phospholid
steroid hormones - involved with absorption, synthesis and transport of lipids
5
Q
golgi body
A
- stack of membrane-bound flattened sacs
- secretory vesicles bring materials to/ from golgi
- protein modification
+ sugar → glycoproteins
+ lipid → lippoprotein
folded into 3D shape
6
Q
mitochondria
A
- spherical/rod-shaped
- surrounded by 2 membranes
fluid-filled space between
inner membrane highly folded into cristae - site of ATP
- self-replicating
- abundant in cell
7
Q
chloroplast
A
- small, flattened structure
- surrounded by double membrane
- has “ thylakoid” membrane” inside, stacked up to form grana which are linked together by lamella( thin, flat piece of thyalkoid
8
Q
flagella
A
- like cillia but longer
- stick out to cell surface surrounded by plasma membrane
- 2 microtubules in central and 9 pairs around
9
Q
cytoskeleton
A
network of protein threads
10
Q
4 functions of cytoskeleton
A
- microtubules and microfilaments support organelles, keeping them in place
- strengthen cells, maintain shapes
- causes movement of materials
- causes cell to move
11
Q
light microscope
A
- max resolution of 2 micrometres/ for whole cells, tissues
- max magnification x 1500
12
Q
Laser Scanning Confocal Microscope
A
- laser bean to scan a specimen, tagged w/ fluorescent dye
→ laser cause dye to fluoresce/ gives off light
→ light is focused thr a pinhole onto a detector
→ detector is hooked up into a computer, which generates an image (3D) - pinhole prevents out of focus light → clearer img
- look at diff depth on specimen
13
Q
2 types of Electron Microscope
A
- Transmission Electron Microscope ( TEM)
2. Scanning Electron Microscope (SEM)
14
Q
- Transmission Electron Microscope ( TEM)
A
- uses electromagnet to focus a beam of electron, which is then transmitted to specimen
- denser part of specimen absorbs more electrons 1 → darker on img
- provide high resolution img
- can be used only on thin specimen
15
Q
- Scanning Electron Microscope (SEM)
A
- scan a beam of electron across specimen
- knocks of e- from specimen, gathered in a cathode ray tube to form img
- lower resolution them TEm
- 3D
