UNIT 1. LIVING ORGANISMS

WHAT TO LEARN Chemical composition of living organisms. The vital functions The structure of cells The type of cells The cell theory

WHAT ARE LIVING THINGS?Organisms with a similar chemical composition, perform three vital functions and are made of cells.

CHEMICAL COMPOSITION

INORGANIC COMPOUNDS

ORGANIC COMPOUNDS

SIMPLE MOLECULES Ex: Water

and minerals

COMPLEX MOLECULES Ex: Sugar,

lipids, proteins, nucleic acids.

THE THREE VITAL FUNCTIONS

NUTRITION INTERACTION REPRODUCTION

Take substances

from the environment

Perceive changes in the environment called stimuli and react to

them

Produce descendents

WHAT IS A CELL?

All living things are made of cells.

It’s the basic unit of life and it can perform the three vital

functions.

Types of living things

UNICELLULAR ORGANISMS

MULTICELLULAR ORGANISMS

ONE CELLEx: Bacteria MANY CELLS

Ex: A dog

They can form groups called COLONIES.

They have TISSUES, ORGANS OR SYSTEMS

LIFE KINGDOMS

MONERA(Unicellular)Ex: Bacteria

and Cyanobacteri

a

PROTOCTISTA(Unicellular and

multicellular)Ex: Protozoa and algae FUNGI

(Unicellular and multicellular)

Ex: Yeast and mushroom

ANIMALS(Multicellular)Ex: A monkey

PLANTS(Multicellular)

Ex: An apple tree

MULTICELLULAR: LEVELS OF ORGANISATION

WITH NO TISSUES

WITH TISSUES BUT NOT ORGANS

WITH ORGANS BUT NOT SYSTEMS

WITH SYSTEMS

-Multicellular algae-Mushrooms-Moulds-Sponges

-Moss-Polyps-Jellyfish

-Gymnosperms-Ferns-Angiosperms-Planarians

-Fish-Reptils-mammals-Birds-Amphibians-Molluscs-Arthropods

THE BASIC STRUCTURE OF ALL CELLS The plasmatic membrane: It surrounds the cell. The cytoplasm: It’s a jelly-like substance. The genetic material (DNA): It controls the

cell’s activities.

TYPES OF CELLS PROKARYOTIC CELLS: (Monera Kingdom)

The DNA floats in the citoplasm. They have a cell wall. Sometimes they have flagella.

EUKARYOTIC CELLS (Protoctist, Fungi, Plant, Animal Kingdom) The DNA is in the nucleus. They have a lot of organelles, like mitochondria. Two types:

Plant cells: They have chloroplasts to perform photosynthesis and a rigid cell wall.

Animal cells: They have centrioles to divide the cell. They have cilia and flagella to move around.

Flagellum Cell wall

Plasmatic membrane

Genetic material Fimbria

Ribosomes

PROKARYOTIC CELL

ºEUKARYOTIC CELL

Chloroplast

Mitochondria

Membrane

Centrioles

Vacuole

Lysosomes

Nucleus

Cell wall

What type of cells are they?

C

A B

ACTIVITIES1. The following sentences are false, correct

them in your notebook.a)All the living things except bacteria are made of

cells.b)All cells have plasmatic membrane, cytoplasm and a

nucleus.c)Eukaryotic cells have a nucleus, but they do not have

any other organelles.d)Eukaryotic plant cells have chloroplasts, but they do

not have mitochondria.2. Why was the microscope important in the

discovery of cells?

3. Classify the following compounds as organic or inorganic:

Glucids:Water:Vitamins:Proteins:Lipids:Nucleic acids:Mineral salts:

4. Match the terms in the three columns:1. Unicellular and prokaryotic2.Unicellular and eukaryotic3. Multicellular without tissues4.Multicellular with tissues but not organs5.Multicellular with organs but not systems6. Multicellular with systems

1. Moss2. Angiosperms3. Arthropod4.Yeast5.Mammal6.Amphibian7.Bacteria8.Sponge9.Algae

a. Monerab. Protoctistc. Fungid.Plantse.Animals

5. Indicate which function the following actions belong to:

a) Eating a fruitb) Running away from a predatorc) Matingd) Emigrating to a warmer areae) Drinking water from a riverf) When flowers open to receive more sunlightg) Laying eggs

6. Complete the table using a X to show if the organelle is present.

PROKARYOTIC EUKARYOTIC ANIMAL

EUKARYOTIC PLANT

Cell wallPlasmatic membraneCytoplasmNucleusDNAMitochondriaChloroplastsCentriolesRibosomes