BIOM 1060 (Module 1)

4 main tissue types

• Epithelia (External surface of the body/ lining of internal glands)

• Connective (Tendons, bones, cartilage, ligaments)

• Muscle (cardiac, skeletal, smooth muscles)

• Neural (neurons)

Superior

Toward the head/ upper part of the body

Inferior

toward the feet/ lower part of the body

Medial

Toward the midline of the body

Lateral

Away from the midline from the body

Anterior

Toward the front of the body

Posterior

Toward the back of the body

Superficial

Close to the surfae of the body

Deep

Further inside the body

Proximal

Close to where a limb attaches to the body

Distal

Further from where a limb attaches to the body

Nucleus

control centre of the cell

contains DNA (genetic material)

Ribosome

Used for protein synthesis

Membrane bound ribosomes - Makes proteins that function in the membrane

Endoplasmic reticulum (rough and smooth)

Rough:

• Covered in rough ribosomes and is what is used to make proteins

Smooth:

• Specialised functions in certain cells (e.g detoxification within the livers and kidneys)

Golgi Apparatus

Accepts transport vesicles from the ER, carrying proteins for further modifications, sorted and then sent outside to other cells and various membranes and organelles.

Lysosomes and peroxisomes

Membrane bound organelles

Lysosomes:

• Break down of organic material inside the cells

Peroxisomes:

• Degrade toxic molecules inside the cell

Mitochondria

Releases energy that is stored in ATP

Carries out aerobic cellular respiration

Protein synthesis

Plasma Membrane (structure)

• Separates intracellular and extracellular fluid

• Determines which molecules move in between

• Phospholipid bilayer where the tail is hydrophobic (hates water) and hydrophilic (loves water)

What molecules can penetrate and not through the plasma membrane

Penetrating molecules:

• Gases (O2 & CO2)

• Water

• Ethanol

Non-penetrating molecules

• Ions

• Glucose & proteins

Difference between active and passive transport

Active (Requires ATP, moving molecules from high to low concentrations):

• Primary and secondary active transport as well as vesicular transport

Passive (Does not require ATP, molecules from high to low):

• Simple diffusion

• Facilitated diffusion

• Osmosis

Difference between simple and facilitated diffusion

Simple diffusion:

• Where small molecules move directly through the cell membrane (O2, CO2)

Facilitated diffusion:

• Molecules move from high to low, however uses the help of proteins such as channel and carrier proteins.

Osmosis

Diffusion of water across a partially permeable membrane.

Isotonic solution - No net movement of water (does not change shape)

Hypotonic solution - water moves into the cell, lower solute concentration outside of the cell (cell will swell)

Hypertonic solution - Water moves out of the cell, higher solute concentration outside of the cell (cell will shrink)

Describe which ions are high in concentration in: a) the intracellular fluid, b) the extracellular fluid.

Intracellular fluid:

• K (potassium) dominates

Extracellular fluid:

• Na (sodium) dominas

This is due to the fact that are sodium pumps pumping 3 Na out of the cell with K pumps pumping 2 K into the cell.

Explain how the Na⁺-K⁺ pump works to move ions across the plasma membrane.

1. 3 Na⁺ bind inside

• Pump opens to the cell

• 3 sodium ions attach

2. ATP is used → ADP + Pi

• ATP is broken down

• This releases energy

3. Na⁺ released outside

• Pump changes shape

• 3 Na⁺ are pushed out

4. 2 K⁺ bind outside

• 2 potassium ions attach

5. Pump returns to shape

• Phosphate (Pi) leaves

• Pump resets

6. K⁺ released inside

• 2 K⁺ enter the cell

Compare and contrast primary and secondary active transport.

Similarities

• Both move substances against their concentration gradient

• Both require membrane transport proteins

• Both are essential for maintaining cellular homeostasis

Differences

• Energy source:

  • Primary → Direct ATP use

  • Secondary → Indirect (ion gradient energy)

• Protein type:

  • Primary → ATPase pumps

  • Secondary → Co-transporters (symport/antiport)

• Dependency:

  • Primary → Independent

  • Secondary → Relies on primary transport

• Examples:

  • Primary → Na⁺/K⁺ pump

  • Secondary → Na⁺–glucose symporter