cell structure
Nucleus
Nuclear membrane
Mitochondrion (pl. Mitochondria)
Vacuoles
~ Membrane is enclosing vacuole known as tonoplast
Ribosomes
- Contain chromatins that control cell activities
- Chromatin contain DNA which is the genetic material
- DNA contain instructions for traits and characteristics and to carry out the cell’s function
- Separated from cytoplasm by nuclear membrane
Nuclear membrane
- Protection from chemicals and substances in the cytoplasm
- Prevents DNA damage which can cause mutation (changes to DNA structure or chromosomes) and deficiency
Mitochondrion (pl. Mitochondria)
- Produce adenosine triphosphate (ATP) from cellular respiration
Vacuoles
- Membrane-bound sacs for storage, digestion and waste removal
- Food vacuoles: formed by phagocytosis
- Central large vacuole – help plant cells maintain shape
~ Membrane is enclosing vacuole known as tonoplast
Ribosomes
- Free or membrane-bound
Cell Membrane
Properties
Fluid Mosaic model (plasma membrane)
Parts of Cell Membrane
- Integral / Intrinsic proteins: though / halfway (hydrophilic)
- Peripheral / extrinsic proteins: on top (hydrophilic)
~ Passageway for certain materials to enter and exit
- Partially permeable property of cell membranes
- Hydrophilic (likes water)
- Faces side with water
~ Lipid (fatty acid tail)
- Hydrophobic (fears water)
- Faces side without water
~ Flexible property of cell membrane
Functions of Cell Membrane
~ Maintaining constant environment inside cell
- Flexible
- Fluid (lateral movement)
- Repair itself
- Strong
Fluid Mosaic model (plasma membrane)
- Cell membrane
- Tonoplast (vacuole membrane)
- Mitochondria membrane
Parts of Cell Membrane
- Proteins
- Integral / Intrinsic proteins: though / halfway (hydrophilic)
- Peripheral / extrinsic proteins: on top (hydrophilic)
~ Passageway for certain materials to enter and exit
- Partially permeable property of cell membranes
- Carbohydrate
- Lipids
- Phospholipid bilayer
- Hydrophilic (likes water)
- Faces side with water
~ Lipid (fatty acid tail)
- Hydrophobic (fears water)
- Faces side without water
- Glycoproteins (proteins with attached carbohydrate chains)
- Glycolipids (lipids with attached carbohydrate chains)
- Cholesterol
~ Flexible property of cell membrane
Functions of Cell Membrane
- Compartmentalise the cell
- Controls entry and exit of substances
~ Maintaining constant environment inside cell
- Increases surface area
- Cell recognition
- Cell communication
- Site of chemical reactions
Cell Transport
Types of Cell Transport
~ Facilitated Diffusion
- Ion channel
- Carrier protein channel
- Phagocytosis
- Pinocytosis
~ Exocytosis
Passive and Active Transport
- Passive Transport
~ Facilitated Diffusion
- Ion channel
- Carrier protein channel
- Osmosis
- Active Transport
- Bulk Transport
- Phagocytosis
- Pinocytosis
~ Exocytosis
Passive and Active Transport
- Passive transport goes down the concentration gradient (from higher concentration to lower concentration) while active transport can go both ways.
- Diffusion is via diffusion while active transport and facilitated transport is via carrier proteins.
- Carrier proteins are ions with binding sites.
- Active transport requires energy (ATP).
- Active transport can go against the conentration gradient hence requiring more energy than diffusion, which goes down the concentration gradient.
- Ions are water-filled and transport soluble substances into the cell.
- Ion channels are more efficient than carrier protein channels.
- Aquaporin is a specialized protein for water transport.
- Specialized cell types have specialized ions and specialized carrier proteins.
- Active site is in an enzyme where chemical reactions takes place while binding site is in a carrier protein where no chemical reactions take place.
DrawingS
Drawing and Labeling of Diagrams
~ No broken lines
~ Lines must be straight
~ No bended lines
~ No arrows
~ Both line and words in pencil
Drawing of Plasma Membrane Structure
- Hydrophilic phosphate head
- Hydrophobic fatty acid tail
~ Glycolipid
~ Extrinsic protein
- Glycoprotein
- Size
- Pencil size
- Thin pencil
- Cross-lines
~ No broken lines
- Labeling
~ Lines must be straight
~ No bended lines
~ No arrows
~ Both line and words in pencil
- Proportion
- Shape
Drawing of Plasma Membrane Structure
- Phospholipid bilayer
- Hydrophilic phosphate head
- Hydrophobic fatty acid tail
~ Glycolipid
- Proteins
~ Extrinsic protein
- Glycoprotein
- Carbohydrate
- Cholesterol (small, interspaced in bilayer) (optional)