Introduction to Life Sciences

Every living organism has different and their own characteristics. Biology, in simple terms, is the study of life and Life Sciences are basically the study of biology. The life sciences comprise of the study of science that includes the study of organisms like plants, animals, microorganisms as well as human beings. However, some life sciences specifically focus on certain type of life.

Characteristics

Living things refer to all those things that have self-sustaining processes. Those organisms that possess life and have the ability to eat, grow, respire, reproduce, obtain as well as use energy for the metabolic process. It also includes those things that are invisible like viruses and bacteria. All the living things collective of everything on Earth are known as organisms. These organisms include the moment, respire, sensitivity, they grow, reproduce, release waste and also consumes the food.

Cells: The Building Block of Life

Life has evolved into an array of shapes and forms. Humans are considered to belong to the most advanced group of organisms. Other higher-level organisms include animals, plants as well as fungi. Viruses are the unusual groups as without the use of a host cell they are 0unable to reproduce.

Organisms are made up of a complex structure or complex organization. All living things are composed of a cell. Cell, the building block of life or the smallest unit of life. Even a single cell has the potential to sustain life. Mostly, the life on Earth remains as a single-celled organism, even though the life evolved into multicellular organisms long time ago.

Cells are divided into two main categories – Prokaryotic Cells and Eukaryotic Cells. Prokaryotic Cells are the cells that are found in the microscopic organisms like bacteria and archaea. The DNA isn’t present in the nucleus and has no specialized structure called organelles. Whereas Eukaryotic cells are those cells that are found in more advanced organisms like animals, plants, and fungi. These cells have a nucleus which contains DNA and has organelles.

Genes: The Basic Unit of Heredity

The basic physical and functional unit of heredity is the gene. It is made up of DNA and varies in size. It is believed that it contains all the information that is required to keep the organism alive. The information from these genes is passed from the parent to the offspring when the organisms reproduce. It is one of the reasons as to why children look similar to their parents.

Evolution: The Theory of Everything

The evolution refers to the change and is the way in which living things change and develop over millions of years. The theory of evolution by the natural selection has given the best explanation for the huge diversity of species on the planet Earth. For over 4 billion years the natural selection is considered to be carving life.

It is considered to be the cornerstone of modern biology. It has driven the development of life with the help of genetic mutations. Biology in itself is a broad field of study and the study of evolution, ecology and genetics are much broader.

Solved Examples

Q1. The longest and largest bone in the human body is __.

Spinal Cord
Humerus
Fibula
Femur

Sol. The correct answer is the option ”d”. The longest and largest bone in the human body is Femur.

Q2. The number of Chromosomes in the human gene is __.

Sol. The correct answer is the option ”c’. The number of Chromosomes in the human gene .