🂱🧬 Bio 1.3 Chemistry basics

Prokaryotic Cell

Pro = NO nucleus

No nucleus No organelles = simple

• Has ribosomes that float freely

• Has a plasma membrane that folds for reactions

• Has DNA

• Has cytoplasm

  • Example: Bacteria

❌ NO nucleus ❌ NO membrane-bound organelles ❌ NO complex internal structure

Eukaryotic Cell

EU = trUE nucleus

Nucleus + Organelles = complex

• Has a complex internal structure

• DNA is inside the nucleus

• Has a nuclear membrane & plasma membrane

• Has membrane-bound organelles

• Has Ribosomes

  • found in organisms such as humans, animals, plants, and fungi

Ribosomes =

Ribosomes make proteins

• they do this by linking amino acids together

ALL cells have ribosomes

• they are in both prokaryotes & eukaryotes

Nucleus =

• Contains the cells DNA

• Controls what the cell does

• Has a nuclear membrane

“contains the genomic content and serves as the control center”

Mitochondria =

Powerhouse

• Performs cellular respiration → uses oxygen to produce:

• ATP = useable cellular energy

Food → mitochondria → ATP → energy

ER =

Manufacturing & transport system

The Endoplasmic Reticulum is an organelle that is an extension of the outer membrane of the nucleus and often contains ribosomes

What are the 2 types of Endoplasmic Reticulum?

Rough ER & Smooth ER

• Rough ER has ribosomes = makes / processes proteins

• Smooth ER does not have ribosomes = makes lipids, and helps detoxify

Golgi =

Post office / the cells distribution center

1. It receives proteins & lipids from the ER

2. It modifies them

3. It sorts them

4. It packages them

5. And then ships them where they need to go

Golgi = google maps : it figures out where things need to go

Lysosome =

Garbage disposal

• Contains digestive enzymes that break down unwanted material in the cell

  • Can break down: Proteins, lipids, nucleic acids, carbohydrates, and cellular debris

Cytoskeleton =

A network of fibers that:

• Gives the cell shape

• Provides support

• Anchors organelles

• Helps with movement

• Helps transport materials inside the cell

What are the 3 parts of the cytoskeleton?

1. Microtubules

   • help transport things around the cell & can form structures like flagella / cilia

     • thickest

2. Microfilaments

   • movement & muscle contraction

     • thinnest

     • made from actin

3. Intermediate filaments

   • provides strength & support to cell

Plasma membrane =

Cell border / security system

• Surrounds the cell / encloses the cytoplasm

• It separates the extracellular (outside) from the intracellular (inside) environment

  • maintaining homeostasis: it keeps the cells content inside, controls interactions with the outside environment, and regulates what enters and exits the cell

Peroxisome =

Detox center

• contains enzymes to break down fats, amino acids, and hydrogen peroxide to neutralize toxins

  • especially important in the liver & kidney cells

    • because those organs are involved in detoxification

What contains genomic content and serves as control center?

What is the double-membrane organelle that is the site of cellular respiration?

What is the double-membrane organelle that generates ATP through cellular respiration?

What is an extension of the outer nuclear membrane, and often contains ribosomes?

What is the distribution center that modifies and ships proteins/lipids?

Collection of proteins that provides structural support, anchors organelles, and changes cell shape =

What encloses the cytoplasm and separates the inside from outside?

What assembles proteins by linking amino acids?

Fimbriae =

They help bacteria stick to surfaces / other cells

• small, short hair-like structures, found on bacterial surfaces

Flagella =

Used for movement

• long, whip-like structures that help bacterial motility by rotating and propelling the organism through liquid

Glycocalyx =

An outer coating that provides protection to bacteria

Fluid mosaic =

Moving phospholipids & proteins

What are the 2 types of membrane proteins?

Integral & Peripheral proteins

• INtegral = IN the membrane

  • can act as channels, receptors, adhesion points

• Peripheral = Perimeter

  • they stay on the outside / inside surface

  • they do not cross the the entire membrane

Glycoproteins =

Glyco = sugar

Glycoprotein = protein + carbohydrate chains attached

• helps cells recognize one another

What are the 3 cell junctions?

Tight = Prevents leaks

• wrap around cells like a belt and prevent fluid from leaking between cells

Desmosome = Strongly holds cells together

Gap = opening / communication

• create tiny channels between cells allowing small molecules like ions, sugars, and amino acids to pass through