Although diverse, insects are quite similar in overall design, internally and externally. The head comprises six fused segments with compound eyes, ocelli, antennae and mouthparts, which differ according According to studies, Monogenea is one of the oldest groups in the phylum Platyhelminthes having evolved from Turbellarians over 100 million years ago.. They have a gonopore on the ventral cephalothorax, and the copulation is direct as male Opiliones have a penis, unlike other arachnids. The ink gland and its associated ink sac empties into the rectum close to the anus, allowing the squid to rapidly discharge black ink into the mantle cavity and surrounding water. scorpion, (order Scorpiones or Scorpionida), any of approximately 1,500 elongated arachnid species characterized by a segmented curved tail tipped with a venomous stinger at the rear of the body and a pair of grasping pincers at the front. Examples: Sea hares, Aplysia, Petalifera, Notarchus, Bursatella, Akera. : Opiliones 6,600 4 Graptolites are a group of colonial animals, members of the subclass Graptolithina within the class Pterobranchia.These filter-feeding organisms are known chiefly from fossils found from the Middle Cambrian (Miaolingian, Wuliuan) through the Lower Carboniferous (Mississippian). The front half of the pouch contains the female gonopore, spermathecal pores, and collateral glands. : Solifugae 1,100 Ticks are external parasites, living by feeding on the blood of mammals, birds, and sometimes reptiles and amphibians. The head comprises six fused segments with compound eyes, ocelli, antennae and mouthparts, which differ according The front half of the pouch contains the female gonopore, spermathecal pores, and collateral glands. They serve as openings for the scorpion's respiratory organs, known as book lungs. The next four somites, 3 to 6, all bear pairs of spiracles. The age of American paddlefish is best Ticks (order Ixodida) are parasitic arachnids that are part of the mite superorder Parasitiformes.Adult ticks are approximately 3 to 5 mm in length depending on age, sex, species, and "fullness". The anatomy of spiders includes many characteristics shared with other arachnids.These characteristics include bodies divided into two tagmata (sections or segments), eight jointed legs, no wings or antennae, the presence of chelicerae and pedipalps, simple eyes, and an exoskeleton, which is periodically shed.. Spiders also have several adaptations that distinguish them from Urchins typically range in size from 3 to 10 cm (1 to 4 in), although the largest species can reach up to 36 cm (14 in). The name urchin is an old word for hedgehog, which sea urchins resemble; they have archaically been called sea They have a gonopore on the ventral cephalothorax, and the copulation is direct as male Opiliones have a penis, unlike other arachnids. Although scorpions are most common and diverse in deserts, they also live in many other habitats. The age of American paddlefish is best Notaspidea: (i) Shell may or may not be present. There is a well-developed cuticle, which may be thick and rigid, giving the animal a box-like shape, or flexible, giving the animal a worm-like shape; such rotifers are respectively called loricate and illoricate. An octopus (PL: octopuses,octopi, or octopodes, see below for variants) is a soft-bodied, eight-limbed mollusc of the order Octopoda (/ k t p d /, ok-TOP--d).The order consists of some 300 species and is grouped within the class Cephalopoda with squids, cuttlefish, and nautiloids.Like other cephalopods, an octopus is bilaterally symmetric with two eyes and a The ink is a suspension of melanin particles and quickly disperses to form a dark cloud that The timing of the origin of ticks is uncertain, though the The cirrus can be everted through the gonopore during copulation. Rotifers have bilateral symmetry and a variety of different shapes. The insect is made up of three main body regions (tagmata), the head, thorax and abdomen. All planaria are hermaphrodites, meaning individual animals have both female and male reproductive parts at the same time. For most populations the median age is five to eight years and the maximum age is fourteen to eighteen years. They serve as openings for the scorpion's respiratory organs, known as book lungs. A possible early graptolite, Chaunograptus, is known from the Middle Cambrian. A possible early graptolite, Chaunograptus, is known from the Middle Cambrian. For most populations the median age is five to eight years and the maximum age is fourteen to eighteen years. All planaria are hermaphrodites, meaning individual animals have both female and male reproductive parts at the same time. A copulatory organ on the tail collects the sperm and transfers it to the partner's seminal receptacle through the female gonopore. They have a rigid, usually spherical body bearing moveable spines, which gives the class the name Echinoidea (from the Greek ekhinos 'spine'). Graptolites are a group of colonial animals, members of the subclass Graptolithina within the class Pterobranchia.These filter-feeding organisms are known chiefly from fossils found from the Middle Cambrian (Miaolingian, Wuliuan) through the Lower Carboniferous (Mississippian). The genital atrium is a common chamber for male and female genital apertures, it opens externally by a gonopore lying ventrally in front of the acetabulum. According to studies, Monogenea is one of the oldest groups in the phylum Platyhelminthes having evolved from Turbellarians over 100 million years ago.. The female has an elongated ovary above the point where the intestine caeca rejoin, from the ovary an oviduct passes in front. Although scorpions are most common and diverse in deserts, they also live in many other habitats. They have a gonopore on the ventral cephalothorax, and the copulation is direct as male Opiliones have a penis, unlike other arachnids. The 7th sternum is boat-shaped in females, and it forms a brood or genital pouch with the 8th and 9th sterna. The ink gland and its associated ink sac empties into the rectum close to the anus, allowing the squid to rapidly discharge black ink into the mantle cavity and surrounding water. Primarily nocturnal, scorpions often Three physical features separate insects from other arthropods: they have a body divided into three regions (called tagmata) (head, thorax, and abdomen), have three pairs According to studies, Monogenea is one of the oldest groups in the phylum Platyhelminthes having evolved from Turbellarians over 100 million years ago.. [pages needed] All others are called secondary sex organs, divided between the external sex organsthe A sex organ (or reproductive organ) is any part of an animal or plant that is involved in sexual reproduction.The reproductive organs together constitute the reproductive system.In animals, the testis in the male, and the ovary in the female, are called the primary sex organs. While many of the species in the group share a number of morphological characteristics, such as a flattened body and being small in size, Monogeneans are divided into two major groups which include monopisthocotyleans, The ink is a suspension of melanin particles and quickly disperses to form a dark cloud that Urchins typically range in size from 3 to 10 cm (1 to 4 in), although the largest species can reach up to 36 cm (14 in). Both male and female cockroaches have ten segments in their abdomen. Sternite 2 forms the basal plate bearing the pectines, which function as sensory organs. : Solifugae 1,100 They have a shark-like body, average 1.5 m (4.9 ft) in length, weigh 27 kg (60 lb), and can live in excess of thirty years. (iii) Gill bipectinate type. The timing of the origin of ticks is uncertain, though the Sternite 2 forms the basal plate bearing the pectines, which function as sensory organs. Photo source: wiki scorpion, (order Scorpiones or Scorpionida), any of approximately 1,500 elongated arachnid species characterized by a segmented curved tail tipped with a venomous stinger at the rear of the body and a pair of grasping pincers at the front. The genital atrium is a common chamber for male and female genital apertures, it opens externally by a gonopore lying ventrally in front of the acetabulum. They serve as openings for the scorpion's respiratory organs, known as book lungs. Order 5. Photo source: wiki Examples: A copulatory organ on the tail collects the sperm and transfers it to the partner's seminal receptacle through the female gonopore. All species lay eggs . The next four somites, 3 to 6, all bear pairs of spiracles. The insect is made up of three main body regions (tagmata), the head, thorax and abdomen. The head comprises six fused segments with compound eyes, ocelli, antennae and mouthparts, which differ according Urchins typically range in size from 3 to 10 cm (1 to 4 in), although the largest species can reach up to 36 cm (14 in). Graptolites are a group of colonial animals, members of the subclass Graptolithina within the class Pterobranchia.These filter-feeding organisms are known chiefly from fossils found from the Middle Cambrian (Miaolingian, Wuliuan) through the Lower Carboniferous (Mississippian). The female has an elongated ovary above the point where the intestine caeca rejoin, from the ovary an oviduct passes in front. (iii) Gill bipectinate type. (ii) Mantle present but without mantle cavity. Primarily nocturnal, scorpions often (iv) Gill and osphradium on the right side of the body. Although scorpions are most common and diverse in deserts, they also live in many other habitats. The age of American paddlefish is best Primarily nocturnal, scorpions often A sex organ (or reproductive organ) is any part of an animal or plant that is involved in sexual reproduction.The reproductive organs together constitute the reproductive system.In animals, the testis in the male, and the ovary in the female, are called the primary sex organs. They have a shark-like body, average 1.5 m (4.9 ft) in length, weigh 27 kg (60 lb), and can live in excess of thirty years. Examples: The female has an elongated ovary above the point where the intestine caeca rejoin, from the ovary an oviduct passes in front. Examples: Sea hares, Aplysia, Petalifera, Notarchus, Bursatella, Akera. Insect morphology is the study and description of the physical form of insects.The terminology used to describe insects is similar to that used for other arthropods due to their shared evolutionary history. [In this image] Planarian reproductive system. [In this image] Planarian reproductive system. Ticks are external parasites, living by feeding on the blood of mammals, birds, and sometimes reptiles and amphibians. (iv) Gill and osphradium on the right side of the body. [In this image] Planarian reproductive system. The name urchin is an old word for hedgehog, which sea urchins resemble; they have archaically been called sea Sternite 2 forms the basal plate bearing the pectines, which function as sensory organs. Both male and female cockroaches have ten segments in their abdomen. (ii) Mantle present but without mantle cavity. Three physical features separate insects from other arthropods: they have a body divided into three regions (called tagmata) (head, thorax, and abdomen), have three pairs Ticks (order Ixodida) are parasitic arachnids that are part of the mite superorder Parasitiformes.Adult ticks are approximately 3 to 5 mm in length depending on age, sex, species, and "fullness". The anatomy of spiders includes many characteristics shared with other arachnids.These characteristics include bodies divided into two tagmata (sections or segments), eight jointed legs, no wings or antennae, the presence of chelicerae and pedipalps, simple eyes, and an exoskeleton, which is periodically shed.. Spiders also have several adaptations that distinguish them from There is a well-developed cuticle, which may be thick and rigid, giving the animal a box-like shape, or flexible, giving the animal a worm-like shape; such rotifers are respectively called loricate and illoricate. A copulatory organ on the tail collects the sperm and transfers it to the partner's seminal receptacle through the female gonopore. The front half of the pouch contains the female gonopore, spermathecal pores, and collateral glands. The ventral side of somite 1 has a pair of genital opercula covering the gonopore. The timing of the origin of ticks is uncertain, though the Squid distract attacking predators by ejecting a cloud of ink, giving themselves an opportunity to escape. (v) The male gonopore is situated at the base of the right rhinophore. (v) The male gonopore is situated at the base of the right rhinophore. Three physical features separate insects from other arthropods: they have a body divided into three regions (called tagmata) (head, thorax, and abdomen), have three pairs For most populations the median age is five to eight years and the maximum age is fourteen to eighteen years. Typical body length does not exceed 7 mm (0.28 in), and some species are smaller than 1 mm, although the largest known species, Trogulus torosus ( Trogulidae ), grows as long as 22 mm (0. Notaspidea: (i) Shell may or may not be present. [pages needed] All others are called secondary sex organs, divided between the external sex organsthe Order 5. The cirrus can be everted through the gonopore during copulation. The cirrus can be everted through the gonopore during copulation. scorpion, (order Scorpiones or Scorpionida), any of approximately 1,500 elongated arachnid species characterized by a segmented curved tail tipped with a venomous stinger at the rear of the body and a pair of grasping pincers at the front. American paddlefish are among the largest and longest-lived freshwater fishes in North America. American paddlefish are among the largest and longest-lived freshwater fishes in North America. The 7th sternum is boat-shaped in females, and it forms a brood or genital pouch with the 8th and 9th sterna. : Solifugae 1,100 Photo source: wiki Insect morphology is the study and description of the physical form of insects.The terminology used to describe insects is similar to that used for other arthropods due to their shared evolutionary history. Typical body length does not exceed 7 mm (0.28 in), and some species are smaller than 1 mm, although the largest known species, Trogulus torosus ( Trogulidae ), grows as long as 22 mm (0. The male has four testes; a short vas deferens arises from the testes and joins a seminal vesicle which enters a penis, the opens by a gonopore below the acetabulum. The male has four testes; a short vas deferens arises from the testes and joins a seminal vesicle which enters a penis, the opens by a gonopore below the acetabulum. An octopus (PL: octopuses,octopi, or octopodes, see below for variants) is a soft-bodied, eight-limbed mollusc of the order Octopoda (/ k t p d /, ok-TOP--d).The order consists of some 300 species and is grouped within the class Cephalopoda with squids, cuttlefish, and nautiloids.Like other cephalopods, an octopus is bilaterally symmetric with two eyes and a The sperm is sometimes packaged in spermatophores and is released through male gonopores that open, often temporarily, on the underside of the animal, roughly two-thirds of the way along the body. They have a rigid, usually spherical body bearing moveable spines, which gives the class the name Echinoidea (from the Greek ekhinos 'spine'). Although diverse, insects are quite similar in overall design, internally and externally. They have a rigid, usually spherical body bearing moveable spines, which gives the class the name Echinoidea (from the Greek ekhinos 'spine'). Both male and female cockroaches have ten segments in their abdomen. The body of a rotifer is divided into a head, trunk, and foot, and is typically somewhat cylindrical. The cirrus or penis, seminal vesicle and prostatic glands are surrounded in a common cirrus sheath or cirrus sac. Insect physiology includes the physiology and biochemistry of insect organ systems.. Both parts share a single opening called gonopore, which is located on the ventral side of the posterior half of the body. An octopus (PL: octopuses,octopi, or octopodes, see below for variants) is a soft-bodied, eight-limbed mollusc of the order Octopoda (/ k t p d /, ok-TOP--d).The order consists of some 300 species and is grouped within the class Cephalopoda with squids, cuttlefish, and nautiloids.Like other cephalopods, an octopus is bilaterally symmetric with two eyes and a The body of a rotifer is divided into a head, trunk, and foot, and is typically somewhat cylindrical. Squid distract attacking predators by ejecting a cloud of ink, giving themselves an opportunity to escape. The ink gland and its associated ink sac empties into the rectum close to the anus, allowing the squid to rapidly discharge black ink into the mantle cavity and surrounding water. The next four somites, 3 to 6, all bear pairs of spiracles. There is a well-developed cuticle, which may be thick and rigid, giving the animal a box-like shape, or flexible, giving the animal a worm-like shape; such rotifers are respectively called loricate and illoricate. The ventral side of somite 1 has a pair of genital opercula covering the gonopore. Both parts share a single opening called gonopore, which is located on the ventral side of the posterior half of the body. Rotifers have bilateral symmetry and a variety of different shapes. American paddlefish are among the largest and longest-lived freshwater fishes in North America. While many of the species in the group share a number of morphological characteristics, such as a flattened body and being small in size, Monogeneans are divided into two major groups which include monopisthocotyleans, : Opiliones 6,600 4 Although diverse, insects are quite similar in overall design, internally and externally. Notaspidea: (i) Shell may or may not be present. (iii) Gill bipectinate type. A possible early graptolite, Chaunograptus, is known from the Middle Cambrian. The genital atrium is a common chamber for male and female genital apertures, it opens externally by a gonopore lying ventrally in front of the acetabulum. Examples: The cirrus or penis, seminal vesicle and prostatic glands are surrounded in a common cirrus sheath or cirrus sac. The male has four testes; a short vas deferens arises from the testes and joins a seminal vesicle which enters a penis, the opens by a gonopore below the acetabulum. Insect physiology includes the physiology and biochemistry of insect organ systems.. The name urchin is an old word for hedgehog, which sea urchins resemble; they have archaically been called sea Insect morphology is the study and description of the physical form of insects.The terminology used to describe insects is similar to that used for other arthropods due to their shared evolutionary history. The ventral side of somite 1 has a pair of genital opercula covering the gonopore. Both parts share a single opening called gonopore, which is located on the ventral side of the posterior half of the body. Rotifers have bilateral symmetry and a variety of different shapes. : Opiliones 6,600 4 The anatomy of spiders includes many characteristics shared with other arachnids.These characteristics include bodies divided into two tagmata (sections or segments), eight jointed legs, no wings or antennae, the presence of chelicerae and pedipalps, simple eyes, and an exoskeleton, which is periodically shed.. Spiders also have several adaptations that distinguish them from The sperm is sometimes packaged in spermatophores and is released through male gonopores that open, often temporarily, on the underside of the animal, roughly two-thirds of the way along the body. All planaria are hermaphrodites, meaning individual animals have both female and male reproductive parts at the same time. The sperm is sometimes packaged in spermatophores and is released through male gonopores that open, often temporarily, on the underside of the animal, roughly two-thirds of the way along the body. Squid distract attacking predators by ejecting a cloud of ink, giving themselves an opportunity to escape. Insect physiology includes the physiology and biochemistry of insect organ systems.. (v) The male gonopore is situated at the base of the right rhinophore. While many of the species in the group share a number of morphological characteristics, such as a flattened body and being small in size, Monogeneans are divided into two major groups which include monopisthocotyleans, All species lay eggs . The body of a rotifer is divided into a head, trunk, and foot, and is typically somewhat cylindrical. [pages needed] All others are called secondary sex organs, divided between the external sex organsthe The insect is made up of three main body regions (tagmata), the head, thorax and abdomen. Typical body length does not exceed 7 mm (0.28 in), and some species are smaller than 1 mm, although the largest known species, Trogulus torosus ( Trogulidae ), grows as long as 22 mm (0. The 7th sternum is boat-shaped in females, and it forms a brood or genital pouch with the 8th and 9th sterna. (ii) Mantle present but without mantle cavity. They have a shark-like body, average 1.5 m (4.9 ft) in length, weigh 27 kg (60 lb), and can live in excess of thirty years. (iv) Gill and osphradium on the right side of the body. Order 5. All species lay eggs . Ticks are external parasites, living by feeding on the blood of mammals, birds, and sometimes reptiles and amphibians. Examples: Sea hares, Aplysia, Petalifera, Notarchus, Bursatella, Akera. Ticks (order Ixodida) are parasitic arachnids that are part of the mite superorder Parasitiformes.Adult ticks are approximately 3 to 5 mm in length depending on age, sex, species, and "fullness". 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