Organisation: Animal Tissues, Organs and Systems

Animal Tissues

Animal tissues are groups of cells that work together to perform a specific function.
There are four main types of tissues: epithelial, connective, muscle, and nervous tissues.
Epithelial tissue covers body surfaces, lines cavities and organs, and forms glands. It acts as a protective barrier and controls secretion and absorption.
Connective tissue supports, binds, or separates other tissues. The role it plays depends largely on the type of extracellular matrix it possesses. Types of connective tissue include blood, bone, and cartilage.
Muscle tissue is specialised for contraction, they facilitate movement in our body. There are three types of muscle tissue: skeletal, cardiac and smooth muscle.
Nervous tissue is specialised to generate, transmit and process information via electrical signals.

Animal Organs

Organs are a group of tissues that work together to perform a specific function or set of functions.
Each organ has a specific role in the body and most organs function as part of a larger organ system.
For instance, the heart, made of muscle tissue, connective tissue, and nervous tissue, pumps blood to deliver oxygen and nutrients throughout the body.
The liver, another example of an organ, processes nutrients from your diet, neutralises harmful substances and makes proteins for blood clotting.

Animal Systems

An organ system includes two or more organs that work together to perform specific functions, forming a coordinated and efficient unit.
The circulatory system, for example, is made up of the heart, blood vessels, and blood. It transports oxygen, nutrients, and other essential compounds, and removes waste products.
The nervous system, which includes the brain, spinal cord, and nerves, transmits and processes information to control body functions.
The digestive system, including organs such as the stomach, liver, and intestines, breaks down food into nutrients that can be absorbed and utilised by the body.
The respiratory system involves the nose, trachea, lungs and more, and it’s responsible for taking in oxygen and expelling carbon dioxide.

Importance of Organisation

The organised structure from cells to systems allows for the efficient functioning of the body as a whole.
Body systems are interconnected, and changes in one can affect the others. For example, the respiratory and circulatory systems must work in sync for oxygen delivery throughout the body.
From tissues to systems, each level of organisation provides a higher level of complexity, increasing the functionality, capacity, and efficiency of the body.

Understanding the organisation and interplay between tissues, organs, and systems is key to understanding how the body works as a whole. The higher the level of organisation, the more complex the structure and function becomes. This complexity is reflected in the multifaceted abilities of an animal to survive and reproduce.