Plants are multicellular organisms with eukaryoticcells. Unlike animals, plants cannot move. Their cells have a cell wall and chloroplasts, which contain a green pigment called chlorophyll, which is involved in photosynthesis.
As all living things, plants carry out the three basic life processes:
- Nutrition: plants can make their own food through a process called photosynthesis, in which plants use the light from the Sun.
- Interaction: plants cannot move but they interact with the world around them by growing towards light and water and by opening and closing their leaves and petals.
- Reproduction: some plants reproduce by spores and others reproduce by seeds.
Watch this video to learn more about Nutrition in plants: the process of Photosynthesis
According to the way they reproduce, we can classify plants intoNon-seed plants(mosses and ferns) andseed plants (gymnosperms and angiosperms)
1. Non-seed plants: they reproduce by producing cells called spores that grow into a new plant.
Mosses
Ferns
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2. Seed plants: they reproduce by producing seedsthat grow into a new plant.
A) Gymnosperms:they do not produce flowers or fruits, the seeds are grouped in cones.
B) Angiosperms:they produce flowers and fruits which contain the seeds. Examples of Angiosperms
Seeds in flower and fruit. Parts of a flower
Here you have a video to understand the differences between gymnosperms and angiosperms better
Algae are simple organisms that belong to the Protist kingdom.
Although they may look like a plant, algae are completely different living things because they do not have the cell and tissue structure of plants. Algae do not have the same structures that land plants do, such as leaves, roots and other organs. The largest and most complex marine algae are called seaweeds, which are multicellular. Unicellular algae are often called phytoplankton.
Parts of seaweeds
The main characteristics of algae are:
They have eukaryotic cells, which means that they have a nucleus and organelles.They can be unicellular or multicellular.
Chlorella (unicellular algae)
Diatoms (unicellular algae)
Giant Kelp (Macrocystis pyrifera, multicellular brown algae)
They are autotrophic, which means that they can produce their own food by photosynthesis. They produce oxygen that is returned to the atmosphere.They have different sizes: from microscopic to hundreds of metres in lengthThey do not have the tissues and organs of plants: they do not have true roots, stems, or leaves. Most algae are aquatic, although some are found in soil or on trees when there is enough moisture. They can be found in freshwater, marine, and moist soil habitats.They have chlorophyll and other pigments for carrying out photosynthesis. Depending on the pigments they have, algae have different colours. The three main colours are:
Red algae (Palmaria palmata, Dulse)
Brown algae (Fucus vesiculosus, Bladderwrack)
Green algae (Ulva lactuca, Sea lettuce)
Did you know? Many algae are beneficial to humans!
Here you have some videos to learn more about these amazing living things:
There are many different animals in the world. Animals can be classified into different groups that share common characteristics. The two main groups of animals are Vertebrates and Invertebrates.
Watch this video to learn more about them:
VERTEBRATES are animals that have a spinal cord or backbone. They can be further classified into five groups or classes: fish, amphibians, reptiles, mammals and birds.
Watch these videos to learn more about vertebrates and their classification:
Most of the animals in the world are INVERTEBRATES. These animals do not have a spinal cord or backbone. Most invertebrates are oviparous, and we classify them into six main big groups: Porifera (sponges), Cnidarians (jellyfish and corals, previously called Coelenterates), Annelids (segmented worms), Molluscs, Echinoderms and Arthropods.
Watch this video to learn more about invertebrates and their classification:
The largest animal group on the planet is ARTHROPODS.
Remember these animals are a group of invertebrates. All arthropods have jointed legs. Another fascinating characteristic that they all have in common is that their body is divided into segments, and many of which, though not all, are protected by an external skeleton or exoskeleton that is used as a shield or shell. Some arthropods bodies do not grow at the same rate as their exoskeleton, therefore making them shed it for a bigger size, a process known as molting.
Here you have a video to learn more about these amazing group of animals, which includes insects (6 legs, ants and butterflies), arachnids (8 legs, spiders and scorpions), crustaceans (10 legs, crabs and shrimp) and myriapods (more than 10 legs, centipedes)
