Resumen Biology Igcse

Biology IGCSE 2009-2010

Ringmer:
• Respiration: Chemical reaction in cells by which energy is produced from food and glucose is broken down. Glucose + Oxygen→ Carbon Dioxide + Water + Energy. C6H12O6 + 6O2 → 6CO2 + 6H2O + Energy
• Irritability/Sensitivity: The ability to respond to changes in the environment and respond to stimuli.
• Nutrition: Taking in of nutrients containing rawmaterials or energy for growth and tissue repair, absorbing and assimilating them.
• Growth: Permanent increase in size by an increase in cell number or cell size (or both)
• Movement: When organism or parts of them are able to move.
• Excretion: Removal of toxic materials from organisms, the waste products of metabolism of cells and substances in excess of requirements.
• Reproduction:Process that makes more of the same kind of organism, organisms produce offspring. Unicellular organisms divide and multicellular organisms reproduce sexually or asexually.

Levels of Organization:
• Atom: The smallest piece of matter.
• Molecule: Two or more atoms bonded together.
• Cells: Building blocks of living things.
• Tissue: A group of cells with the same specific function.(Spongy Mesophyll layer, etc)
• Organ: Group of tissues with same specific function. (Heart, Brain, etc)
• Organ System: Group of organs with same function. (Circulatory System)
• Organism: Living Thing.

Cells:
• Cells are the building blocks of living things. Every living thing is made out of them.
• Nucleus: Controls all the activities of the cell. It contains the genetic information(DNA or chromosomes) of the individual that will be passed on to offspring. It also determines what type of cell the cell will be (blood cell, liver cell, etc)
• Cytoplasm: Jelly-like substance where chemical reactions take place.
• Cell Membrane: Controls the passage of substances in and out of the cell. It is partially permeable. Made of proteins and fats.
• Cell Wall: It gives the cell arigid, fixed shape. Made of cellulose. It is fully permeable. (Lets everything in and out)
• Vacuole: Large, fluid-filled structure. Contains cell sap. It feeds the cell (food reserve).
• Chloroplasts: They contain chlorophyll for photosynthesis. Gives the plant a green colour.
• Mitochondria: Organelle where respiration takes place.
|Animal Cell|Plant Cell |
|- No cell wall. |- Cell wall |
|- Small, temporary vacuole. |- Large, permanent vacuole. |
|- No chloroplasts. |- Chloroplasts |
|- No fixed shape.|- Fixed, rigid shape |







The Transport System:
• A plant’s transport system is made of two types of tubes: xylem vessels and phloem vessels. The cells of these vessels are modified to make them suited to perform their special functions.
• Together, they form the vascular tissue, also referred to as the vascular bundle. The two types of vessels arealways found together, but they occupy different locations in the root and the stem.

| |Xylem |Phloem |
|Made of |dead cells |living cells |
|Cell wallthickness |thick |thin |
|Cell wall material |lignin |cellulose |
|Permeability of cell wall |impermeable |permeable...