Cell structures and organelle

Cell theory

Cell theory

1. All living things are composed of cells

2. The cell is the smallest unit of life

3. Cell arise from pre-existing cells

Aseptate fungal hyphae

many nuclei ir a single cellular unit; challanges the cell theory with the idea that a cell is a single unit with only one nucleus

Phleom Sieve

contain very little cytoplasm and few organelle

Stirated muscle fibres

Multinucleated, larger cells

Mature red blood cells

Do not contain a nucleus

Prokaryotes and Eukaryotic similiarities

1. Plasma membrane

2. Cytoplasm

3. DNA

4. Ribosome

Cell membrane

Phospholipids that seperate interior from its surroundings

Cytoplasm

made up of water and many dissolved solutes like salt, fatty acids, sugar, amino acids, and enzymes.

Needed in order to carry out the metabolic process

DNA

Used as evidence as common ancestry, all living organisms used DNA

Prokaryote ribosomes

70s ribosomes

Eukaryote Ribosome

80s ribosomes

Prokaryote differences

1. No membrane bound organelle

2. Division by binary fission only

3. Cell wall made up of peptidogycan

4. DNA in Nucleoid

5. Flagella rotates

6. DNA circular

7. 70s ribosomes

8. Can have plasmid

9. All unicellular

Eukaryote differences

1. Membrane bound organelle

2. Division by binary fission, Miosis, and Mitosis

3. Cell wall with cellulose(plants) or chitin(fungus)

4. DNA in nucleus

5. Flagella moves laterally

6. Dna linear

7. 80s ribosomes

8. Does not have plasmid

Cell membrane

regulates what materials move in and out of the cell

Nucleoid

Not wrapped arounf protein and comes together as a circle

Cytoplasm

water with dissolved molecules, allows metabolic reactions to take place

Free Ribosome

Builds protein during translation for use in the cell

Bound Ribosomes

Proteins mde from translation that are excreeted after production

Plasmid

extra pieces of DNA that can be shared between bacteria, and carries aintibiotic resistance gene

Cell wall

provides shape, and withstands pressure

Pili

Allows cell to attach to objects, swap DNA from other cells and may harboon DNA in an environment

Capsule

prevents dehydration and allows adhesion

Flagellum

Used in cell locomotion

Nucleus

Contains the DNA which has the instructions on how to make protein via tranlation and transcription

Has a double membrane which allows eukaryotice cells to seperate the activity of gene transcription and translation

Nuleolus

Makes rRNa

Ribosomes

catalysis the synthesis of polypeptides during translation

No exterior membrane

Rough ER

Flattened membranous sacs that syntheisis and transport polypeptides

releases synthesiszed polypeptide in the RER

Surrounds the cell nucleus

Smooth ER

flattened membranous sacs that lacks ribosomes and insteas synthesisizes phospholipids and cholesterole to repair membranes

Golgi Apparatus

modifies polypeptides into their functional state

sorts, concentrates, and packs proteins in vesicles

Vesicles go to the lysosome, plasma membrane, and secretion out the cell via exocytosis

Consists of flattened sacs called cisternae, which are stacked on top of one another

Vesicles

membrane bound sacs that contain and transport materials within the cell

Transport vesicles

buds off one organelle compartment to another in order to transport molecules

Secretiory vesicle

exocytosis, how new phospholpids are added to the cell membrane

Lysosome

hydrolytic enzymes that break down and recycle old cellular molecules

are found in high concentrations in phagocytic white blood cells where they will fuse with and destroy ingested pathogens.

Mitocondriaw

Adapted for the production of ATP synthesis, surounded by double membrane

folds are called cristae

evolved by endosymbiosis

Has his own DNA

Chloroplast

captures light energy water and co2 to produce glucose

contains chorophyll and absorbs pigments, and is green

Vacuole

maintains turgor pressure against the cell wall enabling it to say upright

contains water

Cytoskeleton

not an organelle

maintains shape, enable the division and movement

Micro Tubules

tubulin protein that are used for intracellular transport of organelle and seperation of chromosomes during mitosis

Centrioles

organise the microtubules, playing an important role in cell division

All life has.. MR H GREN

Metabolism, Homeostasis, Nutrition, Movement, Growth, Excretion, and Reproduction

Compartmentalization 

Organelles form compartments in eukaryotic cells that concentrate functions into their own interior spaces. This means that regions of the cell can be specialized and much more efficient. 

Endosymbiotic theory

This theory helps to explain the origin of eukaryotic cells. Smaller unicellular organisms were engulfed and became part of larger organisms, eventually specializing to become organelles within the cell. 

Advantages of multicellularity:

• Longer lifespans because the death of one cell does not prevent other cells to survive.

• Organism are larger – this helps in the exploitation of niches

• Complexity within the organism