<h2 class="section-header">Introduction</h2>
"In the year of 1657 I discovered very small living creatures in rain water." — Antonie van Leeuwenhoek, the Father of Microbiology on discovering cells. Together with Robert Hooke's discoveries, van Leeuwenhoek's findings laid the foundations of microbiology.
<div class="wp-caption alignnone" id="attachment_100035" style="width: 800px"><a href="https://data.ulearngo.com/assets/227f93bf-e51a-479d-a199-190ae9ae6ee0"><img alt="Antonie van Leeuwenhoek" class="size-full wp-image-100035" height="949" src="https://data.ulearngo.com/assets/227f93bf-e51a-479d-a199-190ae9ae6ee0" width="800"/></a>Antonie Philips van Leeuwenhoek was a Dutch businessman, scientist, and one of the notable representatives of the Golden Age of Dutch science and technology. Image credit: Public Domain</div>
<div class="list">
<ul class="bullet">
<li class="item">The invention of microscopes allowed us to see <a href="https://app.ulearngo.com/tutorials/introducing-study-of-life/what-is-life">life</a> at the microscopic level.</li>
<li class="item">Cell walls are present in plants, bacteria and <a data-lesson="kingdom-fungi" data-subject="biology" data-tutorial="classification-introduction" href="https://app.ulearngo.com/biology/classification-introduction/kingdom-fungi">fungi</a> and provide a rigid support structure.</li>
<li class="item">Cell membranes are semi-permeable and have a fluid rather than a fixed structure. Substances move across them by diffusion, osmosis, <a data-lesson="facilitated-transport" data-subject="biology" data-tutorial="cell-transport" href="https://app.ulearngo.com/biology/cell-transport/facilitated-transport">facilitated transport</a> and active transport.</li>
<li class="item">Cells contain organelles with structures adapted to perform specific functions within the cell.</li>
<li class="item">Cells differ in size, shape and structure in order to carry out specialised functions. Cells with similar structures and functions associate to form tissues.</li>
<li class="item">Plant and animal <a data-lesson="prokaryotic-and-eukaryotic-cells" data-subject="biology" data-tutorial="cell-biology" href="https://app.ulearngo.com/biology/cell-biology/prokaryotic-and-eukaryotic-cells">cells</a> differ in many crucial ways.</li>
</ul>
</div>
In <a href="https://app.ulearngo.com/tutorial/biology-101">Biology 101</a>, we discussed the various organic <a data-lesson="first-organic-molecules" data-subject="biology" data-tutorial="evolution-overview" href="https://app.ulearngo.com/biology/evolution-overview/first-organic-molecules">molecules</a> that make up living organisms. In this tutorial, we will look at the cellular level of organisation of living things.
atom \(\rightarrow\) molecule \(\rightarrow\) cell \(\rightarrow\) tissue \(\rightarrow\) organ \(\rightarrow\) system \(\rightarrow\) organism \(\rightarrow\) ecosystem

ad260561-7f24-4cf8-a3f2-b129f5e47c91

Introduction to Cells

Biology studies life and living organisms. Biology can be divided into different sections that cover the morphology, physiology, anatomy, behavior, and so on of living organisms.

Biology

Discover the fascinating world of cells and explore topics such as microscopy, cell theory, membrane models, transport processes, organelles, and the cell cycle.


Introduction to Cells

Track Your Learning Progress