Appunti di Inglese

Biology

Biology is a natural science concerned with the study of life and living organisms. Anything that is living is studied in biology. The word biology comes from the Greek word bios, which means life, and logos, which means study and knowledge. Biology is the study of living things in order to gain knowledge of how they work.

We split it into different branches to make it easier:

• Taxonomy: the science of classifying living things into different families
• Anatomy: the study of internal structure of organs
• Cytology: the study of cells and how they function
• Histology: the study of tissues
• Paleontology: the study of fossils
• Embryology: the study of embryos which are entities that will develop into offspring
• Genetics: the study of heredity and variations

In biology, the cell is the basic unit of life. It is the most basic element in living things. It is able to replicate independently so we...

Often call it the building block of life.

Genes are the basic unit of heredity and evolution is the engine that propels the synthesis and creation of new species. So what does it mean to be alive? An animal, person or plant is considered to be alive when it performs self-sustaining processes like eating, sleeping, reproducing.

In order for things to be considered living they have to perform certain processes. These include nutrition, respiration, excretion, locomotion, reproduction, growth and response.

Nutrition: as opposed to inanimate objects like rocks, living things have to feed on a variety of substances to get the nutritions their bodies need;

Respiration: we all need to breathe in order to perform activity, even though the insects don’t have lungs they still perform respiration, the same with fish who live underwater;

Excretion: the metabolic activities in our body generate waste products that we have to get rid of;

Locomotion: or movement in order to carry out activities.

Living things have to move around in a controlled way, even plants slowly in order to face the sun better;

Reproduction, living things have to reproduce new offspring or else their species who not survive;

Growth, every living thing has to use the nutrition they collect in order to increase their size and grow stronger;

Response, living thing must be sensitive to external stimuli and respond to them like moving away from hot climates or protecting themselves from danger.

Characteristics of the Five Kingdoms of Living Things

The very simplest living things belong to the kingdom monera. Many monera are of microscopic size, there are about 3000 different types or species of monerans. About half the species of Moneran’s are bacteria, while the other half are primitive plant-like organisms like these known as blue green algae. All monerans are unicellular meaning they possess just one cell, moneran’s cells are unique because they lack a nucleus. The nucleus is typically a rounded

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