Highgate resident (yellow lichen on yew tree)

Lichens are symbiotic organisms, where fungi and algae work together to exploit sunlight and create glorious stains on trees and tombs. These are foliose lichens, with small, flat leaf-like structures. The marked contrast of yellow lichen on dark bark is quite common in cemeteries. They are at their best when they catch the setting sun light.


In the eye of the beholder (human retina)

The retina is the light-sensitive layer of tissue inside our eyes. At the top we see the axons going to the optic nerve, to the right of the image. The photoreceptor cells are supported by the pigmented epithelium: the rods (black and white and dim-light vision), and the cones (colour and day-time vision).


The magnificent 7

Chloroplasts in a plant cell, in this case a spinach leaf. Inside the chloroplasts, the stacks of thylakoid membranes are where the action takes place. The dark spots are starch granules. In close proximity are the mitochondria, with curved membranes, and the endothelial reticulum. This system of membranes navigates between the energy producing organelles until it reaches the nucleus, where it also forms the nuclear membrane. 


Purple bacteria II

Purple bacteria or purple photosynthetic bacteria are pigmented by bacteriochlorophyll and carotenoids, giving them a colourful range of purples, pinks and oranges. They photosynthesize without producing oxygen as a by-product. This type of bacteria are proteobacteria which are phototrophic (produce their own food via photosynthesis).

One type, purple sulphur bacteria, deposit elemental sulphur –brimstone – instead. Others oxidise iron to form rusty banded iron formations.


Purple bacteria I

Purple bacteria or purple photosynthetic bacteria are pigmented by bacteriochlorophyll and carotenoids, giving them a colourful range of purples, pinks and oranges. They photosynthesize without producing oxygen as a by-product. This type of bacteria are proteobacteria which are phototrophic (produce their own food via photosynthesis)


Euglena, famous pond water dweller

This single celled organism is a eukaryote, a complex cell with chloroplasts, nucleus, and many other elements inside. They live in fresh water and move to the best spot using a photosensitive eyespot to follow the light.


Liquid tissue

The blood: our liquid tissue. Red cells, white cells and platelets. Bathing in rich plasma, full of gases, nutrients, waste products, chemical signals and messengers. But our blood can also be just the place to invade and reproduce, with devastating results.


St George and the dragon – T cell killing a cancer cell

Taking as an inspiration the classical painting by Paolo Uccello, the knight is the killer T cell in shining armour, here seen attacking a cancer cell. Like Uccello’s pestilent dragon, this cancer cell is complex and disorganized. The red granules are the T cell’s killing weapon, they are able to disturb the permeability of the cancer cell membrane therefore killing it. The cancer cell loses this battle.

Wellcome Images wrote a very nice blog post about this image. You can read it here.


Lost city, hydorthermal vent

This work was selected for the cover of Astrobiology magazine in February 2016. It is my interpretation of the potential cradle of life, an alkaline hydrothermal vent, and is titled Lost City after the first of such structures found, in the bottom of the Atlantic.

The blurb of the magazine said: “Art can create impressions that go beyond the visible, relying instead on our knowledge of the invisible, in this case the flux of carbon and energy that arguably drove the emergence of life. The painting conjures up the labyrinth of micropores inside alkaline vents, as well as a sense of continuous flow, as thermal gradients dissipate through convection and mixing within the porous walls of the vent. As Sojo et al. discuss in this issue, the far-from-equilibrium flux of carbon and energy in Hadean alkaline hydrothermal vents made them ideal electrochemical flow reactors for the origin of life, with a physical topology remarkably analogous, perhaps even homologous, to the structure of autotrophic cells. Sojo et al. review recent work on microbiology and geochemistry and point to a new hypothesis for why bacteria and archaea may have diverged before they even left this cradle of life”.


Working out well

Working out well (silk, 80 x 80 cms). Transversally cut muscle tissue. With a structured fibrous organization and a few blood vessels visible, mitochondria are not visible here as structures, but no prize for guessing where the faulty mitochondria are located.