external sexual
Aquatic arthropods mostly exchange gases through (c) gills; some (like the horseshoe crabs) have book gills. The "book lungs" term usually applies to most arachnids like scorpions and spiders, which are terrestrial; most other terrestrial arthropods exchange gases through special holes in their segments called spiracles, attached to the tracheal tubules/tracheola which connect directly to the tissues.
They have a mouth and an anus like most higher organisms for solid food waste. Gaseous waste for terrestrial arthropods passes through microscopic tubules (tracheoles) and out pairs of openings in body segments (the spiracles); for aquatic arthropods, gills are used to remove nitrogenous waste - particularly useful for highly toxic ammonia.
Lay eggs
Endo = inside. Endoskeletons are skeletons like ours, bones on the inside. Arthropods have EXOskeletons, armour on the outside.All arthropods have segmented bodies with tough exoskeletons made from chitin.
External fertilization and development
They lay an egg, and the egg hatches and is either a nymph or larva, then you should know what happens next!They reproduce sexually, and they reproduce asexually. In most terrestrial arthropods sexual reproduction is carried out internally. In most aquatic arthropods, sexual reproduction occurs externally.
Most aquatic arthropods reproduce by laying eggs. These eggs can be deposited on structures in the water or carried by the female until they hatch. Some aquatic arthropods also undergo complex mating rituals or behaviors before reproducing.
Arthropods reproduce sexually . Fertilization is mostly internal but in some species it is indirect . In most arthropods fertilization is direct . Most arthropods are oviparous i.e. they lay eggs . Metamorphosis takes place .
Internal fertilization .
sexually, like humans
Most of the terrestrial snails are hermaphrodites having the capability of producing both the ova and spermatozoa. The type of reproduction is therefore sexual.
Most often in Arthropods, reproduction is by regular sexual reproduction i.e. by union of a sperm and egg. But variations of the usual process do occur. Aphids (class Insecta), for example, commonly reproduce by parthenogenesis, egg development without fertilization , and produce only females. But later in the summer, some of them convert to being males and then sexual reproduction occurs. Male honey bees are produced by an unfertilized egg. Both of the examples may still be called sexual reproduction since they involve development of the female gamete, that is, the egg. True asexual reproduction would not involve either gamete (sperm or egg) and all of the off spring would be genetically equal.
Vegetative reproduction is most common in plants, however, sexual reproduction is the essence of evolution as it brings genetic recombination.
Most reptiles reproduce sexually although some species reproduce asexually. Upon fertilization, the embryo develops inside an egg with a calcaeous shell. This egg serves to protect the embryo, prevents drying out of the amniotic layer, and allows for efficient gas exchange.
Aquatic arthropods mostly exchange gases through (c) gills; some (like the horseshoe crabs) have book gills. The "book lungs" term usually applies to most arachnids like scorpions and spiders, which are terrestrial; most other terrestrial arthropods exchange gases through special holes in their segments called spiracles, attached to the tracheal tubules/tracheola which connect directly to the tissues.
Most fish reproduce sexually (as per usual there are exceptions). Marine dwelling mammals (dolphins and whales) all reproduce sexually.
Sexual reproduction is the most advantageous for the production of a wide variety of different organisms. The other type or reproduction is asexual which is where one can reproduce on their own.