IB BIO unit 2 ultrastructure, organelles

A

Pili

B

Cell wall

C

Nucleiod

D

Plasma membrane

E

Plasmid

F

Pili attachment point / base of flagella

G

Flagella

How do prokaryotes divide?

Binary fission

A

SeR

B

Ribosomes

C

Golgi apparatus

D

Nucleus

E

Mitochondria

F

reR

G

Lysosome

Nucleus (membrane, 1, contains, form of __)

• circle, double membrane

• Pores (holes) are present 

• Contains genetic information in the form of chromosomes (DNA and associated histone proteins)

What are uncoiled chromosomes referred to in the nucleus? (color, and location)

chromatin: they stain a dark colour and are concentrated at the edges of the nucleus

What happens to mRNA in the nucleus? (location, leaving)

• mRNA is transcribed in the nucleus 

• mRNA leaves the nucleus via the pores
  (DNA is too large to move through the pores)

Nucleolos- dark thing in the middle (function) produces__ essential for __

produces ribosomes, which are essential for protein synthesis.

Histones

A protein associated with DNA

Mitochondria (membrane, abt shape, site of __ by __)

• Has a double membrane

• A smooth outer membrane and a folded inner membrane

• Variable in shape

• Site of ATP production by aerobic respiration

What are the folds within the mitochondria?

Cristae

Free ribosomes (membrane, color and location)

• No membrane

• dark granules in the cytoplasm

80 s ribosomes (cell type, location)

They are found in eukaryotic cells (like plant and animal cells), floating in the cytoplasm or attached to the rough endoplasmic reticulum.

70s (cells, location)

They are found in prokaryotic cells (like bacteria) and inside cell parts like mitochondria and chloroplasts.

Rough Endoplasmic Reticulum (dots on it) (consists of, location, ribosomes, function)

• consists of flattened membrane sacs, cisterna

• Location: near the nucleus

• 80S Ribosomes are attached to the outside of the cisternae are ribosomes

• Function: makes proteins that are transported, by vesicles, to the golgi apparatus

Smooth Endoplasmic Reticulum ( no dots)

no ribosomes present

The Golgi apparatus (wifi icon, if its outside membrane its golgi)

(membrane type, sacs name, differ to rER ribosomes, location, appearance, function)

• flattened membrane

• sacs called cisternae

• Different to rER:

  • No attached ribosomes

  • Often close to the plasma membrane

  • The cisternae are shorter and more curved then the rER ones

• function: processes proteins from the rER. The proteins are then repackaged in vesicles for secretion outside the cell.

Vesicles (membrane, size, function)

• A single membrane with fluid inside

• Size:small

• Function: Used to transport materials inside of a cell

Lysosomes-dark sacs (appearance and membrane, formed by__, function, 3)

• Spherical with a single membrane

• Formed from Golgi vesicles

• They contain digestive enzymes for breakdown of:

  • ingested food in vesicles

  • unwanted/damaged organelles

  • The cell itself

Vacuoles (membrane, plant/animal)

• Single membrane with fluid inside

• In Plant cells vacuoles are large 

• In animals vacuoles are smaller and temporary and used for various reasons, e.g. to absorb food and digest it

Flagellum (appearance, quantity, containing, function)

Thin projection (usually singular) from the cell surface.

Contain microtubules

Used to move the cell

Cilia (containing, function)

Contain microtubules

Used to either move the cell or to move the fluids next to the cell

Microtubules (appereance, function)

• Small cylindrical fibres

• variety of functions, e.g. part of the structure of flagella and they play a role in cell division

Centrioles (group, found in, not present it)

• Consist of two groups of nine triple microtubules

• Are mainly found in animal cells, not present in vascular plants or fungi.

Chloroplasts (some plants only) (which cells, membrane, stacks, within stacks, site of)

• Many, but not all, plant cells contain chloroplasts

• A double membrane surrounds the chloroplast

• Inside are stacks of thylakoids

• Each thylakoid is a disc composed of a flattened membrane

• The site of photosynthesis

Cell wall (plants only) (organelle, secreted by, consist of, its 3)

• not an organelle.

• secreted by all plant cells (fungi and some protists also secrete cell walls).

• Plant cell walls consist mainly of cellulose which is:

  • Permeable 

  • Strong – gives support to the cell 

  • Hard to digest –resistant to being broken down

Cytoplasm (function 2, cells)

• gelatinous fluid that fills the cell

• organelles and materials float and travel through

• plants and animals

A

80s ribosomes

B

Mitochondria

C

reR

D

Plasma membrane

E

Nucleus

F

Golgi apparatus

G

Nuclear envelope

H

Vesicle