Summary All You Need To Know Chapter 1 IGCSE Biology!

IGCSE Revision- Biology
Chapter 1- Characteristics & Classification of living organisms


1.1 Characteristics of organisms
Organism- living thing
M- Movement
R- Reproduction
S- Sensitivity
G- Growth
R- Respiration- ability to break down substances to release energy
E- Exretion
N- Nutrition

RESPIRATION
-​ Chemical reaction
-​ Organisms use this energy from respiration to make other chemical reactions
happen. This is called metabolism.
SENSITIVITY
-​ Internal environment- temperature of the blood OR external environment
(intensity of sunlight)
GROWTH
-​ Growth is the permanent increase in size and dry mass
REPRODUCTION
-​ Making more organisms of the same kind
EXCRETION
-​ Removing waste products from the organism
NUTRITION
-​ Taking in materials that provide chemicals to build up cells

1.2 The biological classification system
Common ancestor: A species that lived in the past and has given the rise of several
other species alive today
SPECIES
-​ Smallest group of classification
-​ A species is a group of organisms that can reproduce with each other to produce
offspring that can also reproduce (fertile)
THE BINOMIAL NAMING SYSTEM