Jacanas (Jacanidae): Characteristics and habitat
By: M E Skeel
Jacanas or lotus birds are distributed widely across the southern hemisphere. They are classified as part of the Charadriiformes, with plovers and lapwings, by some taxonomists, while others consider them to be different enough to deserve their own order. There are eight species in the...
An overview: Hornbills, a tropical or subtropical bird
By: M E Skeel
Hornbills are distinctive birds with large, brightly colored beaks that set them apart from every other order of birds. The 54 species of hornbills are classified in the order Bucerotiformes and divided into two families. In other classification systems, they are included in the Coraciiformes...
The difference between turgidity and wilting in plants
By: Sammy Stein
Turgidity is the state of a cell when its vacuole is full of water so its contents are pushed against the cellwalls. Because cellulose which makes the cell wall is rigid, there is little give and the cell become turgid or rigid in its ultimate...
What is a plant seed
By: Sammy Stein
A plant seed comes about as the result of pollination in which 2 gametes from same (self pollination) or different plants (cross pollination) unite to create a zygote. The zygote develops within the ovary to become an embryo - the beginnings of a new plants-...
Importance of the dispersal of seeds and fruits
By: Sammy Stein
Seeds and fruits contain the next generation of plants. Some plants like annuals die relying completely on the success of their seeds for the next generation whilst others produce few seeds over their lifetime but those seeds are borne in large pods or fruits to...
The ascent of sap in plants
By: Sammy Stein
Sap in plants is a mixture of water and dissolved mineral salts contained in the xylem vessels. When we speak of sap, we often think of a sugary liquid but in plants, the sugary solution in the phloem does not rise in plants but is...
Types of vegetative reproduction in plants
By: Sammy Stein
Vegetative reproduction in plants can be useful because all the progeny will be identical to the parent plant. For horticulturalists, this may be useful if you get an unusually attractive shoot (or sport) from an otherwise unremarkable plant. Commercially, it makes sense to propagate this...
Different types of germination
By: Sammy Stein
Germination is an amazing event. It is when a potential new plant emerges from the seed - that seemingly dead organ which contains the embryonic plant. However, seeds are not dead but dormant. They wait for the right conditions of light, temperature and water to...
An overview of the class Reptilia
By: M E Skeel
Reptiles evolved from early amphibians and rose to dominate the world for hundreds of millions of years. The dinosaurs became extinct at the end of the Cretaceous period but they live on in a sense through the birds. Mammals are also the descendants of one...
An overview of the class Amphibia or Amphibians
By: M E Skeel
Amphibians are important in an evolutionary sense because early amphibians were the ancestors of all reptiles, birds and mammals. They left the water in the Devonian period about 270 million years ago to become the first vertebrates to colonise land. Their dominance was brief, because...

 

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