Hemolymph

A grasshopper has an open circulatory system, where hemolymph moves through interconnected sinuses or hemocoels, spaces surrounding the organs.
Above is a diagram of an open circulatory system. An open circulatory system is made up of a heart, vessels, and hemolymph. This diagram shows how the hemolymph is circulated throughout the body of a grasshopper. The hemolymph is first pumped through the heart, into the aorta, dispersed into the head and throughout the hemocoel, then back through the ostia that are located in the heart, where the process is repeated.

Fluid, analogous to the blood in vertebrates, that circulates in the interior of the arthropod body, remaining in direct contact with the animal's tissues.

- Hemolymph
A grasshopper has an open circulatory system, where hemolymph moves through interconnected sinuses or hemocoels, spaces surrounding the organs.

14 related topics

Alpha

Arthropod

Arthropods (, (gen.

Arthropods (, (gen.

Structure of a biramous appendage.
Alignment of anterior body segments and appendages across various arthropod taxa, based on the observations until mid 2010s. Head regions in black.
Illustration of an idealized arthropod exoskeleton.
Cicada climbing out of its exoskeleton while attached to tree
Arthropod eyes
Head of a wasp with three ocelli (center), and compound eyes at the left and right
Compsobuthus werneri female with young (white)
The nauplius larva of a penaeid shrimp
Marrella, one of the puzzling arthropods from the Burgess Shale
Kylinxia
The velvet worm (Onychophora) is closely related to arthropods
Insects and scorpions on sale in a food stall in Bangkok, Thailand

The haemocoel, an arthropod's internal cavity, through which its haemolymph – analogue of blood – circulates, accommodates its interior organs; it has an open circulatory system.

Venous (darker) and arterial (brighter) blood

Blood

Body fluid in the circulatory system of humans and other vertebrates that delivers necessary substances such as nutrients and oxygen to the cells and transports metabolic waste products away from those same cells.

Body fluid in the circulatory system of humans and other vertebrates that delivers necessary substances such as nutrients and oxygen to the cells and transports metabolic waste products away from those same cells.

Venous (darker) and arterial (brighter) blood
Hemoglobin, a globular protein
green = haem (or heme) groups
red & blue = protein subunits
A scanning electron microscope (SEM) image of a normal red blood cell (left), a platelet (middle), and a white blood cell (right)
Vertebrate red blood cell types, measurements in micrometers
Frog red blood cells magnified 1000 times
Turtle red blood cells magnified 1000 times
Chicken red blood cells magnified 1000 times
Human red blood cells magnified 1000 times
Circulation of blood through the human heart
Basic hemoglobin saturation curve. It is moved to the right in higher acidity (more dissolved carbon dioxide) and to the left in lower acidity (less dissolved carbon dioxide)
Capillary blood from a bleeding finger
Venous blood collected during blood donation
Jan Janský is credited with the first classification of blood into four types (A, B, AB, and O)
Human blood fractioned by centrifugation: Plasma (upper, yellow layer), buffy coat (middle, thin white layer) and erythrocyte layer (bottom, red layer) can be seen.
Blood circulation: Red = oxygenated, blue = deoxygenated
Illustration depicting formed elements of blood
Two tubes of EDTA-anticoagulated blood.

Insects and some mollusks use a fluid called hemolymph instead of blood, the difference being that hemolymph is not contained in a closed circulatory system.

The human circulatory system (simplified). Red indicates oxygenated blood carried in arteries. Blue indicates deoxygenated blood carried in veins. Capillaries join the arteries and veins.

Circulatory system

Several terms redirect here.

Several terms redirect here.

The human circulatory system (simplified). Red indicates oxygenated blood carried in arteries. Blue indicates deoxygenated blood carried in veins. Capillaries join the arteries and veins.
Blood flow in the pulmonary and systemic circulations showing capillary networks in the torso sections
Diagram of the human heart viewed from the front
The pulmonary circulation as it passes from the heart. Showing both the pulmonary and bronchial arteries.
Capillary bed
Diagram of capillary network joining the arterial system with the venous system.
Depiction of the heart, major veins and arteries constructed from body scans
Animation of a typical human red blood cell cycle in the circulatory system. This animation occurs at a faster rate (~20 seconds of the average 60-second cycle) and shows the red blood cell deforming as it enters capillaries, as well as the bars changing color as the cell alternates in states of oxygenation along the circulatory system.
Magnetic resonance angiography of aberrant subclavian artery
The open circulatory system of the grasshopper – made up of a heart, vessels and hemolymph. The hemolymph is pumped through the heart, into the aorta, dispersed into the head and throughout the hemocoel, then back through the ostia in the heart and the process repeated.
Flatworms, such as this Pseudoceros bifurcus, lack specialized circulatory organs.
Two-chambered heart of a fish
Human anatomical chart of blood vessels, with heart, lungs, liver and kidneys included. Other organs are numbered and arranged around it. Before cutting out the figures on this page, Vesalius suggests that readers glue the page onto parchment and gives instructions on how to assemble the pieces and paste the multilayered figure onto a base "muscle man" illustration. "Epitome", fol.14a. HMD Collection, WZ 240 V575dhZ 1543.
Image of veins from William Harvey's Exercitatio Anatomica de Motu Cordis et Sanguinis in Animalibus, 1628

In arthropods, the open circulatory system is a system in which a fluid in a cavity called the hemocoel bathes the organs directly with oxygen and nutrients, with there being no distinction between blood and interstitial fluid; this combined fluid is called hemolymph or haemolymph.

Evolution has produced enormous variety in insects. Pictured are some possible shapes of antennae.

Insect

Insects (from Latin insectum) are pancrustacean hexapod invertebrates of the class Insecta.

Insects (from Latin insectum) are pancrustacean hexapod invertebrates of the class Insecta.

Evolution has produced enormous variety in insects. Pictured are some possible shapes of antennae.
A pie chart of described eukaryote species, showing just over half of these to be insects
Insects with population trends documented by the International Union for Conservation of Nature, for orders Collembola, Hymenoptera, Lepidoptera, Odonata, and Orthoptera. Of 203 insect species that had such documented population trends in 2013, 33% were in decline.
Stylized diagram of insect digestive tract showing malpighian tubule, from an insect of the order Orthoptera
Bumblebee defecating. Note the contraction of the abdomen to provide internal pressure
The tube-like heart (green) of the mosquito Anopheles gambiae extends horizontally across the body, interlinked with the diamond-shaped wing muscles (also green) and surrounded by pericardial cells (red). Blue depicts cell nuclei.
The different forms of the male (top) and female (bottom) tussock moth Orgyia recens is an example of sexual dimorphism in insects.
Gulf fritillary life cycle, an example of holometabolism.
Most insects have compound eyes and two antennae.
A cathedral mound created by termites (Isoptera).
White-lined sphinx moth feeding in flight
The backswimmer Notonecta glauca underwater, showing its paddle-like hindleg adaptation
Perhaps one of the most well-known examples of mimicry, the viceroy butterfly (top) appears very similar to the monarch butterfly (bottom).
European honey bee carrying pollen in a pollen basket back to the hive
Aedes aegypti, a parasite, is the vector of dengue fever and yellow fever
Because they help flowering plants to cross-pollinate, some insects are critical to agriculture. This European honey bee is gathering nectar while pollen collects on its body.
A robberfly with its prey, a hoverfly. Insectivorous relationships such as these help control insect populations.
The common fruit fly Drosophila melanogaster is one of the most widely used organisms in biological research.

The dorsal blood vessel circulates the hemolymph, arthropods' fluid analog of blood, from the rear of the body cavity forward.

Heart

Muscular organ in most animals that pumps blood through the blood vessels of the circulatory system.

Muscular organ in most animals that pumps blood through the blood vessels of the circulatory system.

Human heart during an autopsy
Computer-generated animation of a beating human heart
The human heart is in the middle of the thorax, with its apex pointing to the left.
Heart being dissected showing right and left ventricles, from above
Frontal section showing papillary muscles attached to the tricuspid valve on the right and to the mitral valve on the left via chordae tendineae.
Layers of the heart wall, including visceral and parietal pericardium
The swirling pattern of myocardium helps the heart pump effectively
Arterial supply to the heart (red), with other areas labelled (blue).
Autonomic innervation of the heart
Development of the human heart during the first eight weeks (top) and the formation of the heart chambers (bottom). In this figure, the blue and red colors represent blood inflow and outflow (not venous and arterial blood). Initially, all venous blood flows from the tail/atria to the ventricles/head, a very different pattern from that of an adult.
Blood flow through the valves
The cardiac cycle as correlated to the ECG
The x-axis reflects time with a recording of the heart sounds. The y-axis represents pressure.
Transmission of a cardiac action potential through the heart's conduction system
Conduction system of the heart
The prepotential is due to a slow influx of sodium ions until the threshold is reached followed by a rapid depolarization and repolarization. The prepotential accounts for the membrane reaching threshold and initiates the spontaneous depolarization and contraction of the cell; there is no resting potential.
3D echocardiogram showing the mitral valve (right), tricuspid and mitral valves (top left) and aortic valve (top right).
The closure of the heart valves causes the heart sounds.
Cardiac cycle shown against ECG
Heart and its blood vessels, by Leonardo da Vinci, 15th century
Animated heart
Elize Ryd making a heart sign at a concert in 2018
The tube-like heart (green) of the mosquito Anopheles gambiae extends horizontally across the body, interlinked with the diamond-shaped wing muscles (also green) and surrounded by pericardial cells (red). Blue depicts cell nuclei.
Basic arthropod body structure – heart shown in red
The human heart viewed from the front
The human heart viewed from behind
The coronary circulation
The human heart viewed from the front and from behind
Frontal section of the human heart
An anatomical specimen of the heart
Heart illustration with circulatory system
Animated Heart 3d Model Rendered in Computer

Instead of blood the circulatory fluid is haemolymph which carries the most commonly used respiratory pigment, copper-based haemocyanin as the oxygen transporter.

Beetle

Beetles are insects that form the order Coleoptera, in the superorder Endopterygota.

Beetles are insects that form the order Coleoptera, in the superorder Endopterygota.

Coleoptera at the Staatliches Museum für Naturkunde Karlsruhe, Germany
Fossil and life restoration of Moravocoleus permianus (Tshekardocoleidae) from the Early Permian of the Czech Republic, representative of the morphology of early beetles
Beetle genera were mainly saprophages (detritivores) in the Permian and Triassic. During the Jurassic, herbivorous and then carnivorous genera became more common. In the Cenozoic, genera at all three trophic levels became far more numerous.
Fossil buprestid beetle from the Eocene (50 mya) Messel pit, which retains its structural color
Beetle body structure, using cockchafer.
A: head, B: thorax, C: abdomen.
1: antenna, 2: compound eye, 3: femur, 4: elytron (wing cover), 5: tibia, 6: tarsus, 7: claws, 8: mouthparts, 9: prothorax, 10: mesothorax, 11: metathorax, 12: abdominal sternites, 13: pygidium.
Front view of the head of Lamia textor
Polyphylla fullo has distinctive fan-like antennae, one of several distinct forms for the appendages among beetles.
Acilius sulcatus, a diving beetle with hind legs adapted as swimming limbs
Checkered beetle Trichodes alvearius taking off, showing the hard elytra (forewings adapted as wing-cases) held stiffly away from the flight wings
A beetle's body systems
175x175px
Punctate flower chafers (Neorrhina punctata, Scarabaeidae) mating
The life cycle of the stag beetle includes three instars.
Scarabaeiform larva of Hercules beetle
The ivory-marked beetle, Eburia quadrigeminata, may live up to 40 years inside the hardwoods on which the larva feeds.
Photinus pyralis, firefly, in flight
A dung beetle rolling dung
Hycleus sp. (Meloidae) feeding on the petals of Ipomoea carnea
A camouflaged longhorn beetle, Ecyrus dasycerus
Clytus arietis (Cerambycidae), a Batesian mimic of wasps
Blister beetles such as Hycleus have brilliant aposematic coloration, warning of their toxicity.
172x172px
An Israeli Copper Flower-Chafer (Protaetia cuprea ignicollis) on a crown daisy (Glebionis coronaria)
1: Adult ambrosia beetle burrows into wood and lays eggs, carrying fungal spores in its mycangia. 
2: Larva feeds on fungus, which digests wood, removing toxins, to mutual benefit. 
3: Larva pupates.
Tenebrionid beetle in the Thar Desert
The fogstand beetle of the Namib Desert, Stenocara gracilipes, is able to survive by collecting water from fog on its back.
A scarab in the Valley of the Kings
Cotton boll weevil
Larvae of the Colorado potato beetle, Leptinotarsa decemlineata, a serious crop pest
Coccinella septempunctata, a predatory beetle beneficial to agriculture
Mealworms in a bowl for human consumption
Zopheridae in jewellery at the Texas A&M University Insect Collection
225x225px
"Remarkable Beetles Found at Simunjon, Borneo". A few of the 2,000 species of beetle collected by Alfred Russel Wallace in Borneo
Titan beetle, Titanus giganteus, a tropical longhorn, is one of the largest and heaviest insects in the world.
Scydosella musawasensis, the smallest known beetle: scale bar (right) is 50 μm.
Hercules beetle, Dynastes hercules ecuatorianus, the longest of all beetles
iridescent Protaetia cuprea feeding on thistle
iridescent Protaetia cuprea feeding on thistle

Like other insects, beetles have open circulatory systems, based on hemolymph rather than blood.

Arachnid

Class of joint-legged invertebrate animals , in the subphylum Chelicerata.

Class of joint-legged invertebrate animals , in the subphylum Chelicerata.

Basic characteristics of arachnids include four pairs of legs (1) and a body divided into two tagmata: the cephalothorax (2) and the abdomen (3)
"Arachnida" from Ernst Haeckel's Kunstformen der Natur, 1904
Hubbardia pentapeltis (Schizomida)
Fossil Goniotarbus angulatus (Phalangiotarbi)
Fossil of Kreischeria (Trigonotarbida)
Eukoenenia spelaea (Palpigradi)

Spiders and whipscorpions extend their limbs hydraulically using the pressure of their hemolymph.

Crystal structure of hexameric haemocyanin from Panulirus interruptus refined at 3.2 angstroms resolution

Hemocyanin

Hemocyanins (also spelled haemocyanins and abbreviated Hc) are proteins that transport oxygen throughout the bodies of some invertebrate animals.

Hemocyanins (also spelled haemocyanins and abbreviated Hc) are proteins that transport oxygen throughout the bodies of some invertebrate animals.

Crystal structure of hexameric haemocyanin from Panulirus interruptus refined at 3.2 angstroms resolution
The underside of the carapace of a red rock crab (Cancer productus). The purple coloring is caused by hemocyanin.
crystallographic analysis of oxygenated and deoxygenated states of arthropod hemocyanin shows unusual differences
A hemocyanin active site in the absence of O2 (each Cu center is a cation, charges not shown).
O2-bound form of a hemocyanin active site (the Cu2 center is a dication, charge not shown).

Unlike the hemoglobin in red blood cells found in vertebrates, hemocyanins are not confined in blood cells but are instead suspended directly in the hemolymph.

Grasshopper

Grasshoppers are a group of insects belonging to the suborder Caelifera.

Grasshoppers are a group of insects belonging to the suborder Caelifera.

Fossil grasshoppers at the Royal Ontario Museum
Ensifera, like this great green bush-cricket Tettigonia viridissima, somewhat resemble grasshoppers but have over 20 segments in their antennae and different ovipositors.
Structure of mouthparts
Frontal view of Egyptian locust (Anacridium aegyptium) showing the compound eyes, tiny ocelli and numerous setae
Six stages (instars) of development, from newly hatched nymph to fully winged adult
Romalea microptera grasshoppers: female (larger) is laying eggs, with male in attendance.
Millions of plague locusts on the move in Australia
Cottontop tamarin monkey eating a grasshopper
Grasshopper with parasitic mites
Locusts killed by the naturally occurring fungus Metarhizium, an environmentally friendly means of biological control. CSIRO, 2005
Detail of grasshopper on table in Rachel Ruysch's painting Flowers in a Vase, c. 1685. National Gallery, London
Sir Thomas Gresham's gilded grasshopper symbol, Lombard Street, London, 1563
Fried grasshoppers from Gunung Kidul, Yogyakarta, Indonesia
Sweet-and-salty grasshoppers dish in Japan (Inago no Tsukudani)
Crop pest: grasshopper eating a maize leaf
Egyptian hieroglyphs "snḥm"
A grasshopper beam engine, 1847
Gaudy grasshopper, Atractomorpha lata, evades predators with camouflage.
Lubber grasshopper, Titanacris albipes, has deimatically coloured wings, used to startle predators.
Leaf grasshopper, Phyllochoreia ramakrishnai, mimics a green leaf.
Painted grasshopper, Dactylotum bicolor, deters predators with warning coloration.
Spotted grasshopper, Aularches miliaris, defends itself with toxic foam and warning colours.<ref>{{cite journal |author=Hingston, R.W.G. | year=1927 |doi=10.1111/j.1365-2311.1927.tb00060.x |title=The liquid-squirting habit of oriental grasshoppers| journal=Transactions of the Entomological Society of London |volume=75 |pages=65–69}}</ref>

Like other insects, grasshoppers have an open circulatory system and their body cavities are filled with haemolymph.

A beetle larva performing a rectilinear locomotion.

Animal locomotion

Any of a variety of methods that animals use to move from one place to another.

Any of a variety of methods that animals use to move from one place to another.

A beetle larva performing a rectilinear locomotion.
Dolphins surfing
Scallop in jumping motion; these bivalves can also swim.
Velella moves by sailing.
A pair of brimstone butterflies in flight. The female, above, is in fast forward flight with a small angle of attack; the male, below, is twisting his wings sharply upward to gain lift and fly up towards the female.
Flying fish taking off
Gray squirrel (Sciurus carolinensis) in mid-leap
Leech moving by looping using its front and back suckers
Animation of a Devonian tetrapod
A brachiating gibbon
Physalia physalis
Some remoras, such as this Echeneis naucrates, may attach themselves to scuba divers.
Pacific white-sided dolphins porpoising

Spiders and whipscorpions extend their limbs hydraulically using the pressure of their hemolymph.