What is actually found inside plant and animal cells? Cell Structure What is actually found inside plant and animal cells? STARTER: Compare the structure of these cells.

Compare and contrast...the structure of Prokaryotic and Eukaryotic Cells Cell types are categorised broadly as either Prokaryotic cells or Eukaryotic Cells

A cell whose major organelle’s are contained within membranes Have a proper Nucleus Usually have Mitochondria, Golgi Apparatus, Chloroplasts etc Eukarotes include Animals, Plants and Fungi Eukaryotic Cells

Prokaryotic Cells Cells contain no Nucleus No membrane-bound organelles Mainly unicellular organisms Generally less complex than the Eukaryotes Components float freely within the cytoplasm Bacteria and Archaea Prokaryotic Cells

Watch the following video and observe the complexity of a simple cell. http://www.youtube.com/watch?v=g4L_QO4WKtM

Challenge: look at the image. Remember what you can in 2 mins.

The Cytoskeleton Read the extract from the book. Find out the main jobs of the cytoskeleton.

The Ultrastructure of a Cell Electron microscopes have revealed a lot of new structures inside cells. These are involved in keeping the cell alive. These are called organelles and all have a specific job

The Cytoskeleton – glossary word This has 3 major jobs. It is the network of protein fibres that keep the cells shape by providing a framework. It allows movement of the cell. It aids transport within cells.

2) Movement within the cell Actin – like muscle fibres, can move against each other and allow movement of WBC and organelles.

Microtubules – glossary 25nm diameter tubes made of tubulin that are involved in movement of and within cells. They can move microorganisms through liquids. Other proteins called microtubule motors, on the microtubules allow other things to move Chromosomes during mitosis Vesicles move within the cell These processes involve ATP.

Movement of Eukaryotic cells (eukaryotic cells have a true nucleus)

Cilia(short) and Undulipodia(long) These move cells or have a sweeping motion. Mobility is from the 9 microtubules in a circle around 2 central microtubules. (9+2 arrangement)

Complete the sheet “ The Cytoskeleton” using pages 10-11 to help Key words Actin filaments Microtubules Cilia Flagella Tubulin Microtubule motors Protein

The internal structure of a cell What are the organelles in plant and animal cells? Starter: List as many parts of a cell as possible from memory.

Nucleus Largest structure in the cell 10% of cell structure. The darker patches are stained chromatin . This is surrounded by the nuclear Envelope This has 2 membranes with a fluid between them and they contain nuclear pores. It is connected to the ER. Inside the nucleus is the nucleolus .

Function This contains the genetic information in the form of chromatin. This condenses during cell division to give visible chromosomes. Chromatin is a complex of proteins and DNA. Proteins regulate cell activities and

Nucleolus Produces RNA and ribosomes which are passed to the cytoplasm to be assembled.

Endoplasmic Reticulum structure Rough (RER) and smooth (SER) Flattened and folded membranes called Cisternae which are continuous with the outer membrane. RER –studded with ribosomes. SER – no ribosomes

The RER transports proteins made on the ribosomes for use in or outside the cell. The SER is involved in making lipids for the cell.

Golgi Apparatus A stack of membrane bound, flattened sacs. Recieves proteins from the ER and modifies them and packages them into vesicles. Some are kept inside the cell, some are secreted (Exocytosis)

Lysosomes Contain enzyme lysozyme which breaks down materials. Eg. White blood cells break down microorganisms. Sperm heads contain lysozyme to break down the egg cell membrane.

Chloroplasts Only found in plant cells and some protoctists. 2 membranes separated by a fluid filled space. Inner membrane is continuous with the thylakoids- these look like piles of plates. A stack of thylakoids = a granum Some granum = grana The chlorophyll is present on the thylakoid membranes and intergranal membranes.

Mitochondria Also double membraned – with a fluid filled space Inner membrane is highly folded to form cristae Central part is the matrix Site of Aerobic respiration ATP (adenosine tri phosphate) production

Vacuole Membrane bound Maintains cell stability by pushing the cytoplasm against the membrane. (turgid) Filled with water or ‘sap’ Large in plant cells

Plasma Membrane Found in all cells Controls the entrance and exit of molecules Protein and Lipid

NON membrane bound organelles.

Centriole Animal cells only No membrane. Small protein fibres. Take part in cell division as the spindle fibres which move chromosomes during cell division.

Ribosomes Not membrane bound. Some are free in the cytoplasm and some are bound to the ER. Site of protein synthesis where amino acids are assembled.