SPERM AND EGG CELLS IMAGES. A false-colour scanning electron micrograph of a human egg cell (gold)...

SPERM AND EGG CELLS IMAGES

A false-colour scanning electron micrograph of a human egg cell (gold) surrounded by cumulus cells (orange). Cumulus cells are specialised cells that nourish the large egg cell while it grows in the ovarian follicle.Credit: Yorgos Nikas, Wellcome Images

Human eggHuman egg

A human secondary oocyte (which will later become an egg cell) during in vitro fertilisation, viewed with a light microscope using Nomarski optics, a technique used to highlight cell structure. The small cell at the bottom left is a polar body.

Credit: Spike Walker, Wellcome Images.

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Secondary oocyte during in vitro fertilisationSecondary oocyte during in vitro fertilisation


Egg cell in follicle

Light microscopy image of a transverse cross-section of an immature egg cell (oocyte) in a maturing follicle. Once a month, during the female menstrual cycle, an oocyte matures in one of the many ovarian follicles. As the follicle matures it increases in size, and different cell types are recruited to the developing follicle to support the oocyte before ovulation.

Credit: Dr Ivor Mason, King’s College London, Wellcome Images.

Light microscopy image showing sperm and an egg cell (or ovum) at the moment of conception during in vitro fertilisation. The egg is surrounded by protective cumulus cells around the outside surface, coloured yellow. The sperm need to penetrate these cells and the membrane surrounding the egg, called the zona pellucida, if successful fertilisation is to occur.



Egg and sperm

Digital artwork showing intracytoplasmic sperm injection (ICSI). ICSI is a method of in vitro fertilisation (IVF) that is used to treat infertile couples when standard IVF techniques are not likely to be successful. ICSI is the process of injecting a single sperm cell directly into the egg; it is normally used when the male has a low sperm count or sperm motility is low and fertilisation is unlikely to occur naturally. This illustration shows the egg cell (ovum) being held

at the end of a micropipette. The egg is surrounded by cumulus cells, which provide nutrients to the egg.Credit: Maurizio De Angelis, Wellcome Images.


Intracytoplasmic sperm injection

Light microscopy image of human sperm, showing a sample with average sperm count.Credit: Dr Joyce Harper, UCL, Wellcome Images.


Human sperm sample: average count

Light microscopy image of human sperm, showing a sample with an exceptional sperm count.Credit: Dr Joyce Harper, UCL, Wellcome Images.


Human sperm sample: exceptional count

Confocal microscopy image showing a variety of abnormal human sperm cells. Sperm with different types of head and tail defects surround a group of normal sperm in the centre.Credit: Dr David Becker, Wellcome Images.


Abnormal sperm

Scanning electron microscopy image of numerous sperm trying to fertilise a human egg. In order to successfully fertilise the egg they need to find their way through the tough zona pellucida, the membrane that surrounds and protects the egg.

Credit: Yorgos Nikas, Wellcome Images.


Sperm on the surface of an egg

Seminiferous tubule

Confocal microscopy image of a cross-section through a seminiferous tubule showing the developing sperm; they can be seen as a row of cells with their tails pointing into the lumen (opening) of the tubule. The nuclei are stained blue, and the mitochondria red. Sperm have a large number of mitochondria for energy to allow them to swim towards the egg.

Credit: MRC NIMR, Wellcome Images


Single sperm

Digital artwork of a sperm, showing the head, midpiece and tail. The head of the sperm is surrounded by an acrosome ‘cap’ (blue), which contains enzymes that help the sperm penetrate the outer membrane of the egg to permit fertilisation. The midpiece contains large coiled a mitochondrion (gold) to provide energy to the tail, and two centrioloes (green), which are required for a viable

embryo.Credit: Anna Tanczos, Wellcome Images


Section of a testis

Light microscopy image of a transverse cross-section through a testis. Staining of the tissue reveals the numerous seminiferous tubules - the location of sperm production. Between them are interstitial cells that support sperm production.



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SPERM AND EGG CELLS IMAGES. A false-colour scanning electron micrograph of a human egg cell (gold)...

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