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Frogs have a highly developed nervous system that consists of a brain, spinal cord and nerves. Many parts of frog brains correspond with those of humans. It consists of two olfactory lobes, two cerebral hemispheres, a pineal body, two optic lobes, a cerebellum and a medulla oblongata.
Up to two-thirds of the frog’s body can be frozen but it will still survive. With the arrival of the spring thaw, water re-enters the frog’s cells and their heart starts beating again. It ...
Xenobots built to date have been less than 1 millimeter (0.04 inches) wide and composed of just two things: skin cells and heart muscle cells, both of which are derived from stem cells harvested from early (blastula stage) frog embryos. [7] The skin cells provide rigid support and the heart cells act as small motors, contracting and expanding ...
When frozen, wood frogs have no detectable vital signs: no heartbeat, breathing, blood circulation, muscle movement, or detectable brain activity. Wood frogs in natural hibernation remain frozen for 193 +/- 11 consecutive days and reached an average (October–May) temperature of −6.3 °C (20.7 °F) and an average minimum temperature of −14 ...
"Fewer than a dozen of the 6455 species of frogs in the world are known to have internal fertilization, and of these, all but the new species either deposit fertilized eggs or give birth to froglets."
Reconstruction of Gerobatrachus, possible ancestor of salamanders and frogs. Some, if not all, lissamphibians share the following characteristics. Some of these apply to the soft body parts, hence do not appear in fossils. However, the skeletal characteristics also appear in several types of Palaeozoic amphibians: [6] Double or paired occipital ...
Adult frogs do not have tails and caecilians have only very short ones. [69] Didactic model of an amphibian heart. Salamanders use their tails in defence and some are prepared to jettison them to save their lives in a process known as autotomy. Certain species in the Plethodontidae have a weak zone at the base of the tail and use this strategy ...
A lymph heart is an organ which pumps lymph in lungfishes, amphibians, reptiles, and flightless birds back into the circulatory system. [1] [2] In some amphibian species, lymph hearts are in pairs, and may number as many as 200 in one animal the size of a worm, while newts and salamanders have as many as 16 to 23 pairs of lymph hearts.