ch2 - Eukaryotic and Prokaryotic Cells

name examples of eukaryotic cells

animal

plant

name examples of prokaryotic cells

bacteria

what does ultrastructure of a cell mean

the more detailed structures of a cell - organelles

>can be obtained by using a microscope

name the 12 organelles usually found in eukaryotic animal cells

nucleus

mitochondria

smooth endoplasmic reticulum

rough endoplasmic reticulum

ribosomes

golgi apparatus

vesicles

lysosomes

centrioles

cytoskeleton

flagella

cilia

name 3 structural features and 3 function of nucleus

structure:

-surrounded by double membrane (nuclear envelope) containing nuclear pores by which molecules enter and exit

-chromatin (made of DNA and histones) which condenses to form chromosomes

-nucleolus contains proteins and RNA which combine to form ribosomes

function:

-site of DNA replication and transcription

-site of ribosome synthesis

-controls cells activities since it contains the DNA of cell (which gives instructions for what proteins to produce)

name structural features and 2 function of mitochondria

structure:

-(ch18)

function:

-site of cellular aerobic respiration

-site of ATP production

name structural feature and 2 functions of smooth endoplasmic reticulum

structure:

-network of membranes enclosing flattened sacs called cisternae

function:

-lipid and carbohydrate synthesis

-storage

name 2 structural features and 2 functions of rough endoplasmic reticulum

structure:

-network of membranes enclosing flattened sacs called cisternae

-ribosomes on surface making it rough

function:

-protein synthesis and transportation

what is the difference between SER and RER

RER has ribosomes on its surface

name 2 structural features and function of ribosomes

structure:

-found free floating the cytoplasm or attached to endoplasmic reticulum to form the rough endoplasmic reticulum

-formed in nucleolus and is made up of proteins and RNA

function:

-site of protein synthesis

name structural feature and function of Golgi apparatus

structure:

-cisternae and small vesicles

function:

-modify & package lipids and proteins into vesicles:

>secretory vesicles to leave cell OR specialised vesicles (lysosomes) to stay inside cell

name function of vesicles

function:

-to transport materials around the inside of a cell

name structural feature and 2 function of lysosomes

structure:

-specialised type of vesicles that contain hydrolytic enzymes

function:

-break down waste material such as worn out organelles to reuse materials

-digest pathogens

name 3 structural feature and 3 function of cytoskeleton

structure:

network of fibres found all over the cytoplasm made of 3 components

>microfilaments = responsible for cell movement

>microtubules = create scaffold like structure which provides shape and stability

>intermediate fibres = holds organelles in place which provides mechanical strength

function:

- cell movement

- cell shape and stability

- holds organelles in place

name structural feature and function of centrioles

structure:

-made of microtubules and arrange in pairs to form a centrosome

function:

-produce spindle fibres and attach onto chromosomes during cell division

name structural feature and function of flagella

structure: whip like structures which are long and protrude from some cells

function: enables a cell to move along

name structural feature and function of cilia

structure: hair like structures which are small and protrudes from some cells

function: helps move substances across the surface of a cell in a sweeping motion

describe the 3 step journey taken for protein production

1. protein is synthesized at the ribosomes bound to the RER then enter into cisternae inside RER to be packaged into transport vesicles carried along the cytoskeleton to golgi apparatus

2. at golgi apparatus, protein is modified and packaged into vesicle

3. either lysosome to remain inside cell OR secretory vesicle which will move to cell surface membrane and fuse with it releasing the contents via exocytosis

name the 3 additional organelles usually found in eukaryotic plant cells

cell wall

chloroplast

vacuole

name structural feature and function of cell wall

structure:

-made of cellulose which is freely permeable allowing substances to move in and out

function:

-provides structural support

-acts as defence mechanism by protecting cells from invading pathogens

name structural feature and function of chloroplast

structure:

-(ch17)

function:

-site of photosynthesis

name structural feature and function of vacuole

structure:

-surrounded by tonoplast which separates waste materials inside the vacuole from the rest of the cell

function:

-maintains pressure inside a cell by pushing the cytoplasm against the cell wall and keeping the plant turgid and not wilt

name 2 organelles only found in prokaryotic cells

plasmids

capsule

pili

what are plasmids and name its function

extra genes small circular loops which are additional to the main free floating chromosomal DNA

what is the capsule and name its function

extra layer around the cell wall which provides protection when attacked by antibiotics or WBC

what is pili and name its function

hair-like structures on the surface used to attach prokaryotic cells to other cells and surfaces

name these differences between eukaryotes and prokaryotes:

cell type, size, DNA, ribosomes, organelle types, cell wall

cell type and size:

E = unicellular or multicellular / P = unicellular and much smaller

DNA:

E = linear DNA contained in nucleus / P = main circular chromosomal DNA & plasmids, extra genes

ribosomes:

E = larger 80s / P = smaller 70s

organelle types:

E = contains membrane bound organelles / P = has no membrane bound organelles e.g. no nucleus, mitochondria, RER, SER

cell wall:

E = in plants of cellulose, in fungi of chitin / P = murein