Year 10 Science

BIOCHEMISTRYCells in their EnvironmentCell structure

Cell Theory

• All organisms are composed of cells

• all cells come from pre existing cells

• Cells are the smallest living organisational unit

All Cells

• Cytoplasm is enclosed within an outer cell membrane

• hereditary information is carried in the form of DNA

Cell Organelles

• These have a cell membrane and cytoplasm

• the cytoplasm has many organelles• these organelles include a

membrane bound nucleus• Organelles are similar to organs, but

on a smaller scale

Plant and Animal Cells

Cell Environment

• Normal cell function depends on their extracellular (outside the cell) environment

• cell membranes are permeable (allow to pass through) to water and oil soluble substances (alcohol) and some small molecules

• the make up of extracellular fluid is important to the cell

Cell Environment

• Salt concentrations can affect the passage of water and therefore stability of the cell

• Optimal (best) cell activities could also depend on– temperature– levels of nutrients– pH– removal of wastes

Organelles

• Organelles are specialised structures found within cells.

Golgi Apparatus

Golgi Apparatus

Golgi Apparatus

• It is the despatches department of the cell

• Chemicals are packaged in membranes at the Golgi and then sent out of the cell

Golgi Body

Chloroplasts

Chloroplasts

• Chloroplasts are found only in Plants• They are responsible for Photosynthesis

• They convert inorganic materials such as water and carbon dioxide to useable food such as sugar and starch.

Chloroplasts

• The unique green colour is due to the chemical chlorophyll

• Chlorophyll converts light energy into useable chemical energy

Grana

Mitochondria

Mitochondrium

Mitochondria

• This is the powerhouse of the cell• It converts sugars and starches

into useable energy for cells

Endoplasmic Reticulum

Endoplasmic Reticulum

Endoplasmic Reticulum

• It is the transport system of the cell

• It is able to transport toxic chemicals to the Golgi Body

• It looks like a series of membranes stacked within the cells

Vesicles & Lysosomes

Vesicles & Lysosomes

• Once the toxic chemicals are in the Golgi Body they are packaged

• These packages are membrane bound so as to protect the rest of the cell

• These packages are often sent out of the cell.

• These packages are Lysosomes and Vesicles

Evolution Of Organelles

Pinocytosis