Animal

context: The word "animal" comes from the Latin animalis, meaning having breath, having soul or living being. In everyday non-scientific usage the word excludes humans – that is, "animal" is often used to refer only to non-human members of the kingdom Animalia; often, only closer relatives of humans such as mammals, or mammals and other vertebrates, are meant. The biological definition of the word refers to all members of the kingdom Animalia, encompassing creatures as diverse as sponges, jellyfish, insects, and humans.
qas: answers: text: Latin animalis
question: Where does the word animal come from?

answers: text: having breath, having soul or living being
question: What does the Latin word animalis mean?

answers: text: non-human members of the kingdom Animalia
question: The word animal is usually only used to refer to what?

answers: text: Animalia
question: The biological definition of the word animal refers to all member of what kingdom?

answers: text: sponges, jellyfish, insects, and humans
question: What are some of the creatures included in the kingdom of Animalia?

context: All animals have eukaryotic cells, surrounded by a characteristic extracellular matrix composed of collagen and elastic glycoproteins. This may be calcified to form structures like shells, bones, and spicules. During development, it forms a relatively flexible framework upon which cells can move about and be reorganized, making complex structures possible. In contrast, other multicellular organisms, like plants and fungi, have cells held in place by cell walls, and so develop by progressive growth. Also, unique to animal cells are the following intercellular junctions: tight junctions, gap junctions, and desmosomes.
qas: answers: text: eukaryotic
question: What type of cells do all animals have?

answers: text: collagen and elastic glycoproteins
question: What is the extracellular matrix surrounding eukaryotic cells made of?

answers: text: shells, bones, and spicules
question: What is formed when the collagen and elastic glycoproteins surrounding eukaryotic cells are calcified? 

answers: text: tight junctions, gap junctions, and desmosomes
question: What are the intercellular junctions unique to animal cells?

answers: text: cell walls
question: How are cells held in place in plants and fungi?

context: Predation is a biological interaction where a predator (a heterotroph that is hunting) feeds on its prey (the organism that is attacked). Predators may or may not kill their prey prior to feeding on them, but the act of predation almost always results in the death of the prey. The other main category of consumption is detritivory, the consumption of dead organic matter. It can at times be difficult to separate the two feeding behaviours, for example, where parasitic species prey on a host organism and then lay their eggs on it for their offspring to feed on its decaying corpse. Selective pressures imposed on one another has led to an evolutionary arms race between prey and predator, resulting in various antipredator adaptations.
qas: answers: text: Predation
question: What is the biological interaction where a predator feeds on its prey called?

answers: text: death
question: The act of predation typically results in what for the prey?

answers: text: detritivory
question: What is the consumption of dead organic matter called?

answers: text: their offspring to feed on its decaying corpse
question: Why do parasitic species lay their eggs on their prey?

answers: text: various antipredator adaptations
question: The evolutionary arms race between prey and predator has resulted in what?

context: Among the other phyla, the Ctenophora and the Cnidaria, which includes sea anemones, corals, and jellyfish, are radially symmetric and have digestive chambers with a single opening, which serves as both the mouth and the anus. Both have distinct tissues, but they are not organized into organs. There are only two main germ layers, the ectoderm and endoderm, with only scattered cells between them. As such, these animals are sometimes called diploblastic. The tiny placozoans are similar, but they do not have a permanent digestive chamber.
qas: answers: text: anemones, corals, and jellyfish
question: Ctenophora and the Cnidaria include what sea creatures?

answers: text: both the mouth and the anus
question: The digestive chambers of the Ctenophora and the Cnidaria serve as what?

answers: text: ectoderm and endoderm
question: What are the 2 main germ systems in the Ctenophora and the Cnidaria called?

answers: text: diploblastic
question: What are the Ctenophora and the Cnidaria animals sometimes called?

answers: text: they do not have a permanent digestive chamber
question: What differentiates placozoans from the ctenophora and the cnidaria?

context: Animals have several characteristics that set them apart from other living things. Animals are eukaryotic and multicellular, which separates them from bacteria and most protists. They are heterotrophic, generally digesting food in an internal chamber, which separates them from plants and algae. They are also distinguished from plants, algae, and fungi by lacking rigid cell walls. All animals are motile, if only at certain life stages. In most animals, embryos pass through a blastula stage, which is a characteristic exclusive to animals.
qas: answers: text: Animals are eukaryotic and multicellular
question: What sets animals apart from bacteria  and most protists?

answers: text: heterotrophic
question: What are organisms called that digest food in an internal chamber?

answers: text: lacking rigid cell walls
question: What is another way in which animals are distinguished from plants and algae?

answers: text: animals
question: The blastula stage is a characteristic exclusive to what organism?

context: A zygote initially develops into a hollow sphere, called a blastula, which undergoes rearrangement and differentiation. In sponges, blastula larvae swim to a new location and develop into a new sponge. In most other groups, the blastula undergoes more complicated rearrangement. It first invaginates to form a gastrula with a digestive chamber, and two separate germ layers — an external ectoderm and an internal endoderm. In most cases, a mesoderm also develops between them. These germ layers then differentiate to form tissues and organs.
qas: answers: text: blastula
question: What is the hollow sphere that a zygote initially develops into called?

answers: text: swim to a new location
question: In sponges, how do blastula develop into a new sponge?

answers: text: an external ectoderm and an internal endoderm
question: What are the 2 germ layers formed by most blastula?

answers: text: mesoderm
question: What may be formed between the external ectoderm and an internal endoderm layers?

answers: text: tissues and organs
question: What do the external ectoderm and an internal endoderm layers develop into?

context: Some paleontologists suggest that animals appeared much earlier than the Cambrian explosion, possibly as early as 1 billion years ago. Trace fossils such as tracks and burrows found in the Tonian period indicate the presence of triploblastic worms, like metazoans, roughly as large (about 5 mm wide) and complex as earthworms. During the beginning of the Tonian period around 1 billion years ago, there was a decrease in Stromatolite diversity, which may indicate the appearance of grazing animals, since stromatolite diversity increased when grazing animals went extinct at the End Permian and End Ordovician extinction events, and decreased shortly after the grazer populations recovered. However the discovery that tracks very similar to these early trace fossils are produced today by the giant single-celled protist Gromia sphaerica casts doubt on their interpretation as evidence of early animal evolution.
qas: answers: text: 1 billion years
question: How long ago do some paleontologists believe that animals first appeared?

answers: text: triploblastic worms
question: Fossils found in the Tonian period indicate the presence of what creatures?

answers: text: earthworms
question: Triploblastic worms were comparable in size to what other creatures?

answers: text: around 1 billion years ago
question: When was the beginning of the Tonian period?

answers: text: Gromia sphaerica
question: What produces tracks similar to the fossilized tracks discovered by paleontologists?

context: Animals are generally considered to have evolved from a flagellated eukaryote. Their closest known living relatives are the choanoflagellates, collared flagellates that have a morphology similar to the choanocytes of certain sponges. Molecular studies place animals in a supergroup called the opisthokonts, which also include the choanoflagellates, fungi and a few small parasitic protists. The name comes from the posterior location of the flagellum in motile cells, such as most animal spermatozoa, whereas other eukaryotes tend to have anterior flagella.
qas: answers: text: a flagellated eukaryote
question: It is believed that animals evolved from what?

answers: text: choanoflagellates
question: What are the closest known living relatives of animals?

answers: text: opisthokonts
question: What is the name of the supergroup that animals have been placed in by molecular studies?

answers: text: choanoflagellates, fungi and a few small parasitic protists
question: The opisthokonts also include what other organisms?

answers: text: the posterior location of the flagellum in motile cells
question: Where does the name opisthokonts come from?

context: The remaining animals form a monophyletic group called the Bilateria. For the most part, they are bilaterally symmetric, and often have a specialized head with feeding and sensory organs. The body is triploblastic, i.e. all three germ layers are well-developed, and tissues form distinct organs. The digestive chamber has two openings, a mouth and an anus, and there is also an internal body cavity called a coelom or pseudocoelom. There are exceptions to each of these characteristics, however — for instance adult echinoderms are radially symmetric, and certain parasitic worms have extremely simplified body structures.
qas: answers: text: Bilateria
question: What is the group of animals that often have a specialized head with feeding and sensory organs called?

answers: text: two
question: How many openings in the digestive chamber do animals in the Bilateria group have?

answers: text: mouth and an anus
question: What are the openings in the digestive chambers for animals in the Bilateria group called?

answers: text: coelom or pseudocoelom
question: What is the internal body cavity of animals in the Bilateria group called?

context: Traditional morphological and modern molecular phylogenetic analysis have both recognized a major evolutionary transition from "non-bilaterian" animals, which are those lacking a bilaterally symmetric body plan (Porifera, Ctenophora, Cnidaria and Placozoa), to "bilaterian" animals (Bilateria) whose body plans display bilateral symmetry. The latter are further classified based on a major division between Deuterostomes and Protostomes. The relationships among non-bilaterian animals are disputed, but all bilaterian animals are thought to form a monophyletic group. Current understanding of the relationships among the major groups of animals is summarized by the following cladogram:
qas: answers: text: Porifera, Ctenophora, Cnidaria and Placozoa
question: What are some examples of non-bilaterian animals?

answers: text: bilaterian
question: What are animals whose body plans display bilateral symmetry called?

answers: text: bilaterian
question: Animals in what group are thought to form a monophyletic group?

context: The Ecdysozoa are protostomes, named after the common trait of growth by moulting or ecdysis. The largest animal phylum belongs here, the Arthropoda, including insects, spiders, crabs, and their kin. All these organisms have a body divided into repeating segments, typically with paired appendages. Two smaller phyla, the Onychophora and Tardigrada, are close relatives of the arthropods and share these traits. The ecdysozoans also include the Nematoda or roundworms, perhaps the second largest animal phylum. Roundworms are typically microscopic, and occur in nearly every environment where there is water. A number are important parasites. Smaller phyla related to them are the Nematomorpha or horsehair worms, and the Kinorhyncha, Priapulida, and Loricifera. These groups have a reduced coelom, called a pseudocoelom.
qas: answers: text: Ecdysozoa
question: What groups is named after the trait of growth by moulting or ecdysis?

answers: text: insects, spiders, crabs
question: What are some animals in the Arthropoda group?

answers: text: repeating segments
question: Organisms in the Arthropoda group have bodies that are divided into what?

answers: text: Onychophora and Tardigrada
question: What groups are relatives of the arthropods?

answers: text: Nematoda
question: What is another name for roundworms?

context: Because of the great diversity found in animals, it is more economical for scientists to study a small number of chosen species so that connections can be drawn from their work and conclusions extrapolated about how animals function in general. Because they are easy to keep and breed, the fruit fly Drosophila melanogaster and the nematode Caenorhabditis elegans have long been the most intensively studied metazoan model organisms, and were among the first life-forms to be genetically sequenced. This was facilitated by the severely reduced state of their genomes, but as many genes, introns, and linkages lost, these ecdysozoans can teach us little about the origins of animals in general. The extent of this type of evolution within the superphylum will be revealed by the crustacean, annelid, and molluscan genome projects currently in progress. Analysis of the starlet sea anemone genome has emphasised the importance of sponges, placozoans, and choanoflagellates, also being sequenced, in explaining the arrival of 1500 ancestral genes unique to the Eumetazoa.
qas: answers: text: the great diversity found in animals
question: Why is it more economical for scientists to study a small number of species?

answers: text: fruit fly Drosophila melanogaster and the nematode Caenorhabditis elegans
question: Which organisms were among the first life-forms to be genetically sequenced?

answers: text: they are easy to keep and breed
question: Why are  the fruit fly and the nematode the most intensively studied metazoan model organisms?

answers: text: starlet sea anemone
question: Analysis of what genome has emphasised the importance of sponges, placozoans, and choanoflagellates  in explaining the arrival of 1500 ancestral genes unique to the Eumetazoa?

context: The Lophotrochozoa, evolved within Protostomia, include two of the most successful animal phyla, the Mollusca and Annelida. The former, which is the second-largest animal phylum by number of described species, includes animals such as snails, clams, and squids, and the latter comprises the segmented worms, such as earthworms and leeches. These two groups have long been considered close relatives because of the common presence of trochophore larvae, but the annelids were considered closer to the arthropods because they are both segmented. Now, this is generally considered convergent evolution, owing to many morphological and genetic differences between the two phyla. The Lophotrochozoa also include the Nemertea or ribbon worms, the Sipuncula, and several phyla that have a ring of ciliated tentacles around the mouth, called a lophophore. These were traditionally grouped together as the lophophorates. but it now appears that the lophophorate group may be paraphyletic, with some closer to the nemerteans and some to the molluscs and annelids. They include the Brachiopoda or lamp shells, which are prominent in the fossil record, the Entoprocta, the Phoronida, and possibly the Bryozoa or moss animals.
qas: answers: text: Mollusca and Annelida
question: What are two of the most successful animal phyla?

answers: text: snails, clams, and squids
question: What are some of the animals in Mollusca?

answers: text: earthworms and leeches
question: What are some of the animals in Annelida?

answers: text: common presence of trochophore larvae
question: Why are the Mollusca and Annelida considered to be close relatives?

answers: text: lophophore
question: What are the phyla that have a ring of ciliated tentacles around the mouth called?

context: Several animal phyla are recognized for their lack of bilateral symmetry, and are thought to have diverged from other animals early in evolution. Among these, the sponges (Porifera) were long thought to have diverged first, representing the oldest animal phylum. They lack the complex organization found in most other phyla. Their cells are differentiated, but in most cases not organized into distinct tissues. Sponges typically feed by drawing in water through pores. However, a series of phylogenomic studies from 2008-2015 have found support for Ctenophora, or comb jellies, as the basal lineage of animals. This result has been controversial, since it would imply that that sponges may not be so primitive, but may instead be secondarily simplified. Other researchers have argued that the placement of Ctenophora as the earliest-diverging animal phylum is a statistical anomaly caused by the high rate of evolution in ctenophore genomes.
qas: answers: text: other animals early in evolution
question: Animal phyla that are recognized for their lack of bilateral symmetry are thought to have come from where?

answers: text: sponges
question: Which animal represents the oldest animal phyla?

answers: text: drawing in water through pores
question: How do sponges typically feed?

answers: text: 2008-2015
question: During what time were a series of phylogenomic studies conducted that found support for comb jellies as the basal lineage of animals?

context: Deuterostomes differ from protostomes in several ways. Animals from both groups possess a complete digestive tract. However, in protostomes, the first opening of the gut to appear in embryological development (the archenteron) develops into the mouth, with the anus forming secondarily. In deuterostomes the anus forms first, with the mouth developing secondarily. In most protostomes, cells simply fill in the interior of the gastrula to form the mesoderm, called schizocoelous development, but in deuterostomes, it forms through invagination of the endoderm, called enterocoelic pouching. Deuterostome embryos undergo radial cleavage during cell division, while protostomes undergo spiral cleavage.
qas: answers: text: both groups possess a complete digestive tract
question: What do deuterostomes and protostomes have in common?

answers: text: deuterostomes
question: In which group does the anus form first, with the mouth developing secondarily?

answers: text: schizocoelous development
question: What is the process in which cells fill in the interior of the gastrula to form the mesoderm called?

answers: text: enterocoelic pouching
question: What is the process in which the mesoderm is formed through invagination of the endoderm called?

answers: text: radial cleavage
question: What do deuterostome embryos undergo during cell division?

context: The Platyzoa include the phylum Platyhelminthes, the flatworms. These were originally considered some of the most primitive Bilateria, but it now appears they developed from more complex ancestors. A number of parasites are included in this group, such as the flukes and tapeworms. Flatworms are acoelomates, lacking a body cavity, as are their closest relatives, the microscopic Gastrotricha. The other platyzoan phyla are mostly microscopic and pseudocoelomate. The most prominent are the Rotifera or rotifers, which are common in aqueous environments. They also include the Acanthocephala or spiny-headed worms, the Gnathostomulida, Micrognathozoa, and possibly the Cycliophora. These groups share the presence of complex jaws, from which they are called the Gnathifera.
qas: answers: text: Platyhelminthes
question: What is another name for flatworm?

answers: text: flukes and tapeworms
question: What are some parasites included in the Platyhelminthes group?

answers: text: lacking a body cavity
question: What does acoelomates mean?

answers: text: Gastrotricha
question: What are the flatworms closest relative?

answers: text: in aqueous environments
question: Where are the rotifera most prominent?

context: Most animals indirectly use the energy of sunlight by eating plants or plant-eating animals. Most plants use light to convert inorganic molecules in their environment into carbohydrates, fats, proteins and other biomolecules, characteristically containing reduced carbon in the form of carbon-hydrogen bonds. Starting with carbon dioxide (CO2) and water (H2O), photosynthesis converts the energy of sunlight into chemical energy in the form of simple sugars (e.g., glucose), with the release of molecular oxygen. These sugars are then used as the building blocks for plant growth, including the production of other biomolecules. When an animal eats plants (or eats other animals which have eaten plants), the reduced carbon compounds in the food become a source of energy and building materials for the animal. They are either used directly to help the animal grow, or broken down, releasing stored solar energy, and giving the animal the energy required for motion.
qas: answers: text: eating plants or plant-eating animals
question: How do most animals use the energy of sunlight?

answers: text: light
question: What do plants use to convert inorganic molecules into carbohydrates, fats, proteins and other biomolecules?

answers: text: chemical energy
question: What does photosynthesis convert the energy of sunlight into?

answers: text: become a source of energy and building materials for the animal
question: When an animal eats plants or another animal that has eaten plants, what happens to the reduced carbon compounds in the food?

answers: text: giving the animal the energy required for motion
question: What happens with the reduced carbon compounds in the food are broken down releasing stored solar energy?