1.2 - Cell Structure and Organisation Flashcards
What do eukaryotic cells contain?
Membrane bound organelles, which are enclosed in the cytoplasm. Most disguinshed one being the nucleus.
What form of measurement is used for cells and organelles?
Micrometres, um
What system is used for units?
Syteme Internationale
Name the 12 organelles within an animal cell.
- Nucleolus
- Nuclear pore
- Nuclear envelope
- Chromatin
- Rough endoplasmic recticulum
- Ribosomes
- Golgi apparatus
- Mitochondrion
- Lysosome
- Vesicle
- Centriole
- Plasma
Name the 16 organelles of a plant cell.
- Nucleolus
- Nucleus
- Nuclear pore
- Rough endoplasmic recticulum
- Smooth endoplasmic recticulum
- Ribosomes
- Golgi apparatus
- Mitochrondrion
- Tonoplast
- Vacuole
- Vesicle
- Chloroplast
- Cell membrane
- Cell wall
- Cytoplasm
- Plasmodesa
What is the size of the nucleus?
10-20 um
What is the function of the nucleus?
It contains DNA and proteins, which combine to make chromosomes, which direct protein synthesis as they are the site of transcription.
What is the structure of the nucleus? (5 features)
- 2 membranes
- first one being the nuclear envelope, passing large molecules like mRNA
- second one is the continuous endoplasmic recticulum
- nucleoplasm contains chromatin (coils of DNA with protein)
- a small spherical body called nucleolus which is site of formation for rRNA, ribosomes)
What is the size of mitochondrion?
Cylindrical and are 1-10nm in length
What is the function of mitochondia?
Produce ATP in aerobic respiration
What cells need more mitochondia?
Metabolically active cells (eg muscle)
How is the shape of mitochondria efficient?
The cylinder shape reduces diffusion distance between the edge and the centre, making aerobic respiration more efficient.
Where are chloroplasts found?
Found in photosynthesising tissue in plant cells
What are the function of chloroplasts?
Turns the suns radiation into chemical energy usable by organisms.
What is the endosymbiotic theory?
A theory in which suggests chloroplasts and ribosomes once existed as singular organisms, but over time have become a permanent feature needed in cells (‘symbiotic’)
What is the structure of the endoplasmic recticulum?
Parallel double membrane forming flattened sacs with interconnected, fluid filled spaces called cisternae.
What is the function of the endoplasmic recticulum?
Allows the transport of materials though a cell
What is the difference between RER and SER?
SER -lacks ribosomes, associated with the synthesis and transport of lipids.
RER - has ribosomes on the outer surface and transports proteins.
What are the size of ribosomes?
70s in pro, 80s in euk
Structure of ribsomes?
- one large and one small subunit
- made in nucleolus from rRNA and protein
Function of ribosomes?
Many, including protein synthesis and polypeptide production.
What process does a golgi apparatus go through?
Vesicles with polypetides pinch off and fuse with golgi body
The proteins are modified and packaged, and then at the other end, the vesicles are pinched off
What are the 5 functions of the golgi apparatus?
- acronym!
-produce enzymes
-secreting carbs
-producing glycoprotein
-transporting and storing lipids
-forms lysosomes
Every Cow Grazes Long Leaves
What are lysosomes?
Small, temporary vacuoles with a single membrane, formed when pinched off golgi apparatus