How are tissues organised in complex organisms?

Tissues in complex organisms are organised into organs, which then form organ systems to perform specific functions.

In complex organisms, tissues are not just randomly scattered. They are meticulously organised to form structures known as organs. Each organ is designed to perform a specific function or a set of functions. For instance, the heart, an organ, is made up of cardiac muscle tissue, nerve tissue, and connective tissue, all working together to pump blood throughout the body.

The organisation of tissues goes beyond just forming organs. Several organs come together to form an organ system. Each organ system is responsible for a major physiological function. For example, the digestive system, which includes organs like the stomach, liver, and intestines, is responsible for breaking down food, absorbing nutrients, and expelling waste.

The organisation of tissues into organs and organ systems allows complex organisms to maintain homeostasis - a stable internal environment. This is crucial for the survival of the organism. For instance, the nervous system and endocrine system work together to regulate body temperature, blood pressure, and blood glucose levels among other things.

This hierarchical organisation, from cells to tissues, tissues to organs, and organs to organ systems, is a fundamental characteristic of complex organisms. It allows for a division of labour, where different cells, tissues, and organs perform different functions, contributing to the overall survival and well-being of the organism.

In summary, the organisation of tissues in complex organisms is a highly structured and coordinated process. It involves the formation of organs from different types of tissues, and these organs then working together in organ systems to carry out the major functions necessary for the organism's survival.