Download ORGANIZATION OF LIVING THINGS

ORGANIZATION OF LIVING THINGS
1.1. Characteristics of living things.
A living thing is an organism that is able to perform three vital functions:
nutrition, interaction and reproduction. All living things are made of similar
substances and they are formed by cells.
1.2. The cells.
A cell is the smallest unit of living thing capable of performing the three vital
functions: nutrition, interaction and reproduction.
Cells have some characteristics in common which are always present:
 Plasmatic membrane.
 Cytoplasm.
 DNA or genetic material.
Types of cells.
The cells can be classified into prokaryotic cells or eukaryotic cells.
 Prokariotic cells. Their DNA placed in the cytoplasm. It is the
characteristic cell of Monera kingdom organisms (bacteria).
 Eukaryotic cells. Their DNA is placed inside a compartment, called the
nucleus. It is the characteristic cell of protoctists, fungi, plants and
animals.
Eukaryotic cells can be divided into animal eukaryotic cells and plant
eukaryotic cells.
1.3. Unicellular and multicellular organisms.
Unicellular organisms.
They are formed by one single cell which performs all their vital functions.
They are small,simple organisms.
Multicellular organisms.
They are composed of many cells. In most multicellular organisms the cells that
belong to the same kind join to form more complex structures, called tissues.
Tissues form organs that organize into systems.
Key vocabulary:
Perform (v.)
Cell (n.)
Organism (n.)
Functions (n.)
Organ (n.)
ACTIVITIES
1. Write down the differences between eukaryotic and prokaryotic cells.
2. Define the term “living thing”.
3. Write down the three vital functions.
4. State whether the following sentences are true or false:
a) Bacteria are multicellular organisms.
b) All multicellular organisms´cells are identical.
c) Bacteria are organisms with prokaryotic cells.
5. Read the chart , then make sentences to describe the cells: Eukarysdfotic
cells are found in animals.
Found in
size
nucleus
complexity
Eukaryotic cells
animals
big
yes
complex
Prokaryotic cells
bacteria
small
no
simple