Chapter 2- Organisation of the Organism

Definition of Cell wall

A tough layer outside the cell membrane

Definition of Cell membrane

A very thin layer surrounding the Cytoplasm

Definition of Cytoplasm

A jelly-like material that fills the cell

Definition of Vacuole

A fluid-filled space in the cell, separated from the cytoplasm by a membrane

Definition of Nucleus

A structure containing DNA (in the form of chromosomes)

Definition of Mitochondria

A small structure in the cell, where Aerobic Respiration releases energy from Glucose.

Definition of Ribosomes

Very small structures that use information on DNA to make protein molecules

Definition of Chloroplast

Small structures found inside some plant cells where photosynthesis takes place

Structures in Plant cell

Cell wall, Cell membrane, Cytoplasm, Vacuole, Nucleus, Mitochondria, Ribosomes, Chloroplasts

Structures in Animal Cell

Cell membrane, Cytoplasm, Vacuole, Nucleus, Mitochondria, Ribosomes

Structures in Bacterial Cell

Cell wall (not cellulose (peptidoglycan)), Cell membrane, Cytoplasm, Ribosomes, Circular DNA, Plasmids

Structures in Bacterial Cell

Cell wall (not cellulose (peptidoglycan)), Cell membrane, Cytoplasm, Ribosomes, Circular DNA, Plasmids

Definition of Plasmids

Small, circular DNA found in some prokaryotic cells in addition to the main, much large circle of DNA

Definition of Specialized Cells

Cells that have a particular function to perform and is modified to help them carry out that function effectively

Function and Modification of Ciliated Cell

Function: Movement of mucus upwards in the trachea and bronchi

Modification: Has hair-like structures (Cilia)

Function and Modification of Root Hair Cell

Function: Absorption of water and mineral ions

Modification: Large surface area to increase uptake/ absorption

Function and Modification of Palisade Mesophyll Cells

Function: Photosynthesis in Leaves

Modification: Large number of Chloroplasts on the surface

Function and Modification of Red Blood Cells

Function: Transport Oxygen and Nutrients

Modification: Small, flat and flexible, contains Haemoglobin

Function and Modification of Sperm cells

Function: Male gamete in sexual reproduction

Modification: Tail to swim, Head that contains enzymes to get into egg cell, middle piece packed with mitochondria for energy

Function and Modification of Egg Cells

Function: Female gamete in sexual reproduction

Modification: Cytoplasm contains nutrients for the growth of early embryo

Definition of Cell

The smallest unit from which all organisms are made of.

Definition of Tissue

A group of similar cells that work together to perform a particular function

Definition of Organ

A group of tissues that work together to perform a particular function

Definition of Organ System

Several organs that work together to perform a particular function

Definition of Organism

A living thing

Formula of Magnification

Size of image / Size of actual object

Convert 1mm to micrometer (μm)

1mm = 1000 μm