Stills Gallery
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An unusual AmoebaThis network of cytoplasm is a rare, single-celled undescribed species of Amoeba which displays "shuttle streaming": the cytoplasm oscillates back and forth along the tubular pseudopodia. |
A more conventional species of AmoebaThis Amoeba is full of vacuoles containing partially digested food particles. The clear cytoplasm on the left is rich in actin and is forming pseudopodia that determine the direction the cell is moving. |
An Acellular Slime MoldThe lacy, yellow cytoplasm belongs to a giant single-celled slime mold that has grown over the surface of a Petrie dish, enveloping and digesting tiny fragments of oatmeal. The most active pseudopodia are at the top left. |
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Protective armourMany tiny cells have protective cell walls that, in this species of Mallomonas, consist of extraordinarily intricate scales made from pure silica. There are several different types of scales here, all fitting together in a regular pattern. |
EndosymbiosisThe several cells of this unusual amoeba are green because they contain green algal cells which have taken up residence inside the host cell; the two organisms have become completely integrated over many millennia and thus given rise to a new type of cell. This process, endosymbiosis, was critical in the evolution of eukaryotic cells, accounting for the origin of mitochondria and chloroplasts. |
A Real DragThis diatom Licmorphora (a type of alga) grows as beautiful fan-shaped colonies that attach to something solid by their tough rubbery stalk. Quite often, that something is a boat and so these cells are a major contributor to those tiresome organisms which cause biofouling and thus have to be scraped off at regular intervals. |
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'This large, predatory single-celled alga often blooms in huge numbers, in which event
the oceans may become phosphorescent. This species catches prey organisms with the
curved appendage, dragging them into the groove on the left from where they are sucked
into the cell. <br><br>From <i>Microscopic Life and Predatory Tactics.</i>',4))
',
'This cell belongs to a group called the desmids which have long entranced
microscopists with their elegant, symmetrical shape. Each cell consists of
two identical half cells; during cell division two new, perfectly formed half
cells are created within a couple of hours.<br><br>
From <i>Living Cells videodisc</i> and <i>Microscopic Life.</i>',4))
)
; fertilization',
'Many algae, like other cells, undergo sexual reproduction when a rapidly
swimming sperm cell seeks out and fertilizes a large female egg cell. This
sperm cell displays frenetic activity when near the female cell, which is
emitting a powerful attractant, rather like a perfume. <br><br>
From <i>Microscopic Life</i> and <i>Living Cells.</i>',4))
 mating','These two cells, compatible mating types, seek each other out, make contact with their delicate flagellar and finally fuse. The elaborate mating dance is beautiful to watch and after some hours leades to the formation of a resistant diploid spore. <br><br>
From <i>Microscopic Life</i> and <i>Living Cells</i> videotape.',4))
',
'This odd shaped cell is just one of the dinoflagellates which constitute a significant part of the phytoplankton in oceans and freshwater. The large trailing flagella does not seem to do much; swimming is brought about by a second flagellum tightly coiled around the cell.<br><br>
From <i>Microscopic Life</i> and <i>Living Cells</i>',4))
)
',
'The beautiful green globes of this freshwater alga are clearly visible to the naked eye. Several generations of the organism are visible with tiny embryo colonies inside the parent colonies.<br><br>
From <i>Microscopic Life</i> and <i>Living Cells</i>',4))
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'Euglenoids have a spiral coat or <em>pellicle</em>. In this species, the pellicle is rigid and decorated with a pattern of bumps. Many euglenoids in contrast have a flexible pellicle and the cells undergo very dynamic writhing and twisting, changing their shape continuously.<br><br>
From <i>Microscopic Life</i> and <i>Living Cells</i>',4))
 oogonium and antheridium',
'This large algae has complex and beautiful reproductive structures, one containing the egg cell, the other producing thousands of tiny sperm. The antheridium on the left opens like a flower to release sperm which are attracted to the oogonium on the right. Sperm cells fertilize the oogonium through tiny gaps in the coronet, the ring of cells on top.<br><br>
From <i>Living Cells</i>',4))
 of many plant tissues such as those covering flowers, contain special cells such as these colourful hairs. The purpose of hair cells is ofter obscure but in many cases they help protect the delicate tissues.<br><br>
From <i>Living Cells</i> videodisc',4))
 feeding',
'This tiny animal captures selected prey cells using a mass of active threads which trap them and steer them into its gullet. The threads here are just opening after being retracted. From .<br><br>
From <i>Predatory Tactics</i>',4))
 feeding',
'This view shows the maw of the rotifer open and some unfortunate green algae which have been trapped and swallowed. The threads, barely visible here, actively flick the prey into the capacious maw.<br><br>
From <i>Preadatory Tactics</i>',4))
 feeding',
'This large single celled predator uses its flagella to sweep nearby cells close enough for them to be swallowed. Many ciliates use this vacuum cleaner principle during feeding, employing their cilia which are otherwise used for swimming.<br><br>
From <i>Living Cells</i> and <i>Predatory Tactics.</i>',4))
)
',
'These cells form a colony which makes their feeding mechanism, the same as that of <i>Stentor</i>, more efficient. The feeding currents are generated by a fringe of very active cilia around the upper edge of the cell.<br><br>
From <i>Predatory Tactics</i>',4))
',
'Diatoms grow in huge numbers in the oceans and the over 10,000 species all have different, elaborately sculpted walls of pure silica. Each of these cells produces four beautifully curved, very thin spines which are hollow. Presumably they protect the colony against predators.<br><br>
From <i>Diatoms</i>',4))
',
'This single-celled animal extends fine, rigid threads outwards; when other cells touch the threads, they stick and are then pulled inwards and eaten. Each thread has a core of tightly bundled microtubules. The cell here was filmed in dark field illumination.<br><br>
From <i>Microscopic Life</i> and <i>Living Cells</i>',4))
)
',
'This colonial flagellate resembles <i>Volvox</i> in organization, but the cells are very different. They belong to the Chrysophytes, or Golden Brown algae. Each cell is covered with minute silica scales and the colony spins as it swims through the water.<br><br>
From <i>Living Cells</i> and <i>Microscopic Life</i>',4))
)
)
',
'Each cell in this tiny, actively swimming colony forms its own vase-shaped cell wall. After cell division one daughter cell inherits the old wall while the other emerges and secretes a new wall.<br><br>
From <i>Microscopic Life</i> and <i>Living Cells</i> videodisc',4))
',
'This rare marine cell forms a beautiful star-shaped skeleton out of pure silica; it swims slowly using its single flagellum. These skeletons are present in huge numbers in fossil deposits from ancient oceans.<br><br>
From <i>Microscopic Life</i> and <i>Living Cells</i> videodisc',4))
)
',
'Many algae produce different pigments and can change their colour. This green alga is common in transitory ponds, puddles and perhaps even your bird-bath; the thick gelatinous wall protects it from drying out.<br><br>
From <i>Microscopic Life</i> and <i>Living Cells</i>',4))
 dividing',
'Because they are protected by rigid, silica walls, diatoms have evolved special mechanisms to undergo growth and cell division. The wall is composed of many segments which are added continuously as the cell grows<br><br>
From <i>Microscopic Life</i> and <i>Diatoms</i>',4))