Kingdom Animalia

Animalia:

Of all the different kingdoms, the animal kingdom is the most diverse in appearance. Some may look similar, and some may look completely different from one another. But what’s an animal? Well, an animal is multicellular, eukaryotic heterotrophs whose cells lack cell walls. There are two different groups of animal who are classified by a very simple principle, which is if either they have backbone or not. Animals that do not have a vertebral column are called invertebrates, and those who have a vertebral column are called vertebrates. These unique organisms need 7 things in order to survive: Feeding, Respiration, Circulation, Excretion, Response, Movement, and Reproduction.

The animal kingdom is a kingdom with many different phyla: Porifera, Cnidaria, Platyhelmintes, Namatoda, Annelida, Molluska, Arthropoda, Echinodermata, and Chordata.

Porifera:

Sponges are asymmetrical organisms, meaning that they have no front or back ends, and no left or right. Sponges are classified as animals because they have all the requirements needed to be a animal: multicellular, heterotrophic, and no cell walls. The bodies of the sponges are formed by a wall around a large cavity in which water is circulated continually. The spores that are located in the body wall enables the water to go through the sponge, which provides a simple mechanism of feeding, respiration, circulation, and excretion. These organisms can either reproduce sexually or asexually; the sperm from a sponge is released into the surrounding water. The water currents carry the sperm t other sponges The sperm enters another sponge through pores and they are carried to the eggs, then the fertilization occurs.

Cnidaria:

Cnidarians are soft-bodied carnivores, and they are characterized by the singing tentacles arranged in a circle around their mouth. There are two basic groups of Cnidarians: Polyp, and Medusa.

A polyp is a cylindrical body with arm-like tentacles. This organism is characterized by their mouth pointing upward. They are normally attached to the base, and as a result they can't move. Unlike polyps, medusas have bell-shaped body with the mouth on the bottom. Although, they belong to different groups, they share many similarities. They both have body walls that surround an internal cavity (gastrovascular cavity).

These organisms can move by many different ways, such as jet propulsion, and muscle contractions. They can also reproduce both sexually and asexually, by budding or by external fertilization in water.

Platyhelmintes:

These organisms are soft and flattened worms, that why they are known as Flatworms. There are three things that characterize Flatworms from any other organisms in the animal kingdom. They have three embryonic germ layers: Endoderm, Mesoderm, and Ectoderm. They also have bilateral symmetry, meaning that only a single imaginary line can divide the body into two equal halves. Another of their characteristics is that they have cephalization, meaning that there’s a concentration of sense organs and nerves on the front anterior, front, side of the body.

Unlike annelids, flatworms don't have coelom formed between their tissues, but they do have enough cephalization to have what’s called a head. These organisms can reproduce by two different ways: by using cilia (swim), or by muscle contractions.

Flatworms can reproduce either sexually or asexually due to the fact that they are hermaphrodites, meaning that they have both male and female reproductive organs. Two worms need to join in a pair, and they deliver sperm to each other. The eggs are laid within a few weeks (Sexual Reproduction). On the other hand, asexual reproduction takes place by fission, in which the organism splits in two, and each half grows new parts to become a complete organism.

Namatoda:

Organisms that are part of the Namatoda kingdom are free-living organisms that inhabit soil, salt flats, aquatic sediments, and water. They might also live as parasites of plants or animals. These organisms are known also as roundworms. Like the flatworms, these organisms develop from three germ layer, but they have a space between the mesoderm and the endoderm (tube within a tube).

Their digestive tract has two openings, one is the mouth where they ingest all the food, and the other one is the anus, where all the feces come out from. The anus is located in the posterior opening of the digestive tract. The inner tube , as you can see in the picture, is the digestive tract, and the outer tube is the body wall. Roundworms move by using their muscles, just like snakes. They reproduce sexually using internal fertilization, which is when the male deposits sperm in the female’s reproductive tract.

Annelida:

These organisms are characterized by their segmented bodies, and from there is where their names come from, Annellus is Greek means segment. Unlike Namatodes, their bodies are divided into two segments by a coelom, and the two segments are often very similar. These organisms with segmented bodies have atrue coelom, which is lined with the mesoderm (one of the three germ layers).

Annelids have to major groups of body muscles that function as part of a hydrostatic skeleton. They use this muscles fro movement, by alternately contracting them. They reproduce sexually, Annelids attach one to another and exchange sperm in order for the fertilization to occur.

Molluska:

Mollusks are soft-bodied animals, and they are very unique because they usually have an internal or external shell. There are many types of mollusks, such as snails, slugs, clams, squids and octopi, but they are often really similar. One of their similarities if that all of them have a free-swimming larva stage called trochophore, before becoming adults. At the larva stage this organisms can be also classified as annelids , so we can clearly see their evolutionary relationship and that they probably evolved from a common ancestor. Another of their similarities is their body plan, they all have five parts: the shell, mantle cavity, foot, gills, digestive tract. They all normally have them but arranged in different ways. Mollusks are able to move in many different ways, like by rippling motion of the foot, or jet propulsion. Many reproduce sexually by external fertilization; they release great amount of eggs and sperm in the water and the fertilization occurs, then the free-swimming larva is created.

Arthropoda:

Like the Annelids, arthropods also have segmented bodies surrounded by a tough external cover called exoskeleton. This external cover made from protein and a carbohydrate called chitin. These organisms vary greatly in color, shapes, size and toughness. They are unique for their jointed appendages. Arthropods move by using a well develop group of muscles, that we can see that is something that has being evolving from each kingdom, that are coordinated by the nervous system. They reproduce by internal fertilization. Terrestrial arthropods have reproductive organs that place sperm inside the female’s body. On the other hand, aquatic arthropods may have inter or external fertilization. External fertilization is when both eggs and sperm are released in the water and they join together.

Echinodermata:

These organism are characterized by their spiny skin and unlike arthropods, they don’t have exoskeleton instead they have an internal skeleton. They are also characterized by a water vascular system, and suction cup-like structures called tube feet. The water vascular system carries out many essential body functions in echinoderms, such as respiration, circulation, and movement. Most adults echinoderms exhibit five-part radial symmetry. Their body parts, which usually occur in multiples of five, are arranged round the central of the body. These organisms normally move by using the tube feets and a thin layer of muscles fibers. Many times they just crawl along the ocean floor by a combined action of the tube feet and the muscles of the body wall. Echinoderms reproduce sexually by external fertilization, which is when the eggs and sperm are released into the water.

Chordata:

Organisms must have four key characteristics to be chordates: Hollow nerve cord, Notochord, Pharyngeal pouches, and a tail that extends beyond the anus.

The dorsal hollow nerve cord is very important in this organisms. It runs along the back part of the body, and nerves brach from this cord at regular intervals.The Notochord is a long supporting rod that runs through the body.Pharyngeal pouches are paired structures in the throat region that are used for gas exchange like gills in fish. All chordates have tails that extends beyond the anus at some of their life. They normally move by alternately contracting paired sets of muscles on either side of the backbone, this creates a series od S-shaped curves that move down the fishes body.The fins help to propel the fish forward.Fishes normally lay down eggs that can either be fertilize externally or internally. Oviparous developthe embryos outside their bodies, but ovoviparous delop the embryo inside the mother’s body.

Kingdom Plantae

Kingdom Plantae:

Plants are multicellular eukaryotes that have cell walls made of cellulose. They develop from multicellular embryos and carry out photosynthesis using green pigments, chlorophyll a and b.

There are four main things that plants in general need to survive: Sunlight, Water and Minerals, Gas Exchange, and Movement of Water and Nutrients.

Sunlight: Plants use the energy from sunlight to help them do the process of photosynthesis. Because of that many plants have evolved and adapted over the time so they are able to maximize the light absortion.

Water and Minerals: All cells need water to survive and to do the process of photosynthesis, so they have created specialized structures to distribute all the water and minerals absorbed to all the parts of the plant.

Gas Exchange: Plants need oxygen to support respiration, and they need carbon dioxide to do the process of photosynthesis

Movement of Water and Nutrients: Is very important that plants are able to distribute well the water and nutrients that they acquire from their roots and many plants have specialized tissues that make that happen.

Plants can divide into four groups based on three important things: water-conducting tissue, seeds, and flowers: Bryophytes, Pteridophytes, Gymnosperm, and Angiosperm.

Bryophytes:

Unlike other plants, Bryophytes do not have vascular tissues; therefore, they are low-growing plants that can be found in moist, shaded areas. These organism have life cycles that depend on water for reproduction, but because of the lack of vascular tissue, these plants can only draw up water a few centimeters above ground, this keep them relatively small.

Their method of reproduction is quite simple. The capsules relive spores that will land in a female gametophyte. Then the sperm will get to the egg and the fertilization will occur.

Pteridophytes:

These organisms were the first plants to have vascular tissue specialized to conduct water, so they could grow larger than the Bryophytes. Another thing that differs bryophytes from other vascular plants is that they have true roots, leaves, and stems. Roots are underground organs that absorb minerals. Water-conducting tissues are located in the center of the root. Leaves are photosynthetic organs that contain one or more bundless of vascular tissue. This vascular tissue is gathered into veins made if xylem and phloem. Stems are supporting structures that connect roots and leaves, carrying water and nutrients between them. Pteridophytes have a simple way of reproduction. Spores are relieved from the sporangium and later on become young gametophyte. When the gametophyte matures it has the antheridium (where the sperm is located) and the Archegonium (where the eggs are located). And when the fertilization occurs the sporophyte embryo is created.

Gymnosperm:

Gymnosperms are called seed plants because they bear their seeds directly in the surface of the cones. Gymnosperms include conifers, such as pines and spruces, as well as palm-like plants called cycads, ancient ginkgoes, and the very weird gnetophytes. Unlike mosses and fern, seed plants do not require water for fertilization of gametes, and because of that they can live almost everywhere. These organisms reproduce by the process of pollination. One of the main characteristics of the gymnosperm is that they produce cones, as well as flowers.

Angiosperms:

Angiosperms have unique reproductive organs known as flowers. These organs are a huge advantage for them because they attract animals like bees that help the process of pollination. Flowers contain ovaries, which are surrounded and protected by the seeds. Another unique characteristic of the angiosperm is a thick wall of tissue surrounding the seed known as fruit. There are two different groups of angiosperms: Monocots and Dicots.

Monocots and Dicots are named after the number of seed leaves, or cotyledons, in the plant embryo. Monocots have one seed leaf, and dicots have two. Monocots have parallel veins, while dicots have branching veins. Monocots flowers are often in multiple of three, and dicots flowers are often in multiples of four and five. Monocots have vascular bundles scattered throughout the stem, while dicots have vascular bundles arranged in a ring. Monocots ha fibrous roots, and dicots have taproots.

Kingdom Fungi

Kingdom Fungi:

Fungi are eukaryotic organisms who acquire their source of energy from other organism (heterotrophs). Their cell walls are made up with chitins, but, unlike animal fungi, do not ingest food. Instead, they digest food outside their bodies and then absorb it. Many fungi feed by absorbing nutrients from decaying organisms in the soil. Many of them also live as parasites, absorbing nutrients from the bodies of their hosts. Fungi are composed by tiny filaments called hypae, structures that might contain one or two nucleus. The bodies of multicellular fungi are composed of many hypae joined together into a thick mass called mycelium. Most fungi reproduce both sexually and asexually. There are four groups of Fungi: Zygomycota, Ascomicota, Basidiomycota, and Deuteromicota.

There is something that characterizes Zygomycetes, which is that they contain zygospore, a resting spore that contains zygotes formed during the sexual phase of the organisms.

Unlike other fungi, some organisms from the phylum Ascomicota are large enough to be visible when they grow above the ground. They are very unique for their reproductive structure, sexual spores that are found in sac-like structures called an ascus. Ascus are formed within the fruiting body.

Basidiomycota are very unique for their specialized reproductive structure that resembles a club. The reproductive spores are called basidium. Basidia are found on the gills that grow on the underside of mushroom caps. Club fungi are the mushrooms, puffballs, and shelf fungi. All the organisms part of the phylum Basidiomycota are really important forest decomposers.

Many of the fungi are classified by their sexual phase in their life cycle. Organisms on the phylum Deuteromicota are those organisms that are not placed in any other phyla because researchers have never been able to observe their sexual phase, because they don’t have a sexual phase.

Kingdom Protista

Protists:

The kingdom Protist is a group with large biodiversity that may include more than 200 000 species. Biologists have argued for years the best way to classify protists. They are defined less by what they are and more by what they are not: A protist is a eukaryote organism that does not belong to the kingdoms a Plantae, Animalia, or Fungi. Although most protists are unicellular, quite a few are not. Some protists actually consist of hundreds or even thousands of cells but are still considered protists because they are very similar to other that are truly unicellular.

Protist comes from the word “protista” that comes from the Greek, which actually means “the very first. The first eukaryotic organism on earth, which appeared nearly 1.5 billion years ago, were protists. There are two major groups of Protists: Animal-like Protists (protozoans), the Plant-like Protists (unicellular algae) and the Fungus-like Protists.

Animal-like Protists:

Like animal this organism are heterotrophs, meaning that they absorb energy from a different organism. Animal-like protists can easily be distinguished by the way the move, there are the Zooflagellates, Sarcodines, Ciliates and Sporozoans.

Zooflagellates are those organism that swim using flagellas, whip-like things that allow a cell to move. Most of these organisms have either one or two flagellas, although a few species have many. Many live in lakes and streams, places where they can absorb nutrients from decaying organic material. On the other hand, others live inside larger organism, taking advantage of the food that they provide. Most zooflagellates reproduce asexually by the process of cell division, which results in two genetically identical cells.

Sarcodines move using a very unusual method which is projection of cytoplasm, also known as pseudopods. Sarcodines are animal-like organisms that use pseudopods for feeding and movement. These organisms are able to capture and digest particles of food and even other cells. They do this by surrounding their meal, and then take it inside themselves to form a food vacuole.

Members of the phylum Ciliophora, known as ciliates, use cilia for feeding and movement. Cilia is a hair-like thing similar to a flagella. The internal structure of cilia and flagella are exactly identical. Ciliates are found in aquatic environments, both fresh and salty. Under most conditions, ciliates reproduce asexually by mitosis.

Many animal-like protists live as parasites of animals. They do not move at all. Under the the right conditions, a sporozoite can attach itself to a host cell, penetrate it, and then live whitin it as a parasite.

Plant-like Protists:

These unicellular organisms contain a green pigment called chlorophyll, and they also are able to do photosynthesis. There are four phyla of plant-like protists: euglenophytes, dinoflagellates, chrysophytes and diatoms.

Euglenophytes are organisms that have two flagella but no well wall. They are very similar to zooflagellates, but they produce chloroplasts. Euglenophytes inhabit places like ponds and lakes, and if they can’t find sunlight to do photosynthesis they can also live as heterotrophs. Euglenas reproduce asexually by the process of binary fission.

Dinoflagellates are divided into the autotrophs and the heterotrophs. These organisms generally have two flagellates and a thick wall of cellulose that protects the cell. Like euglenophytes, these organisms reproduce asexually by the process of binary fission.

Chrysophytes are a diverse group of protists that have gold-colored chloroplast. The cell wall of some of them contains pectin rather than cellulose, while other contain both. Chrysophytes generally store food in the form of oil. They reproduce both sexually and asexually.

Diatoms produce thin, delicate cell walls rich in silicon. These walls are shaped like two piece of petri dish or flat pillbox, with one side fitted into the other. The cell walls have fine lines and patterns that almost seem to be carved into their glass-like brilliance.

Fungus-like Protists:

Fungus-like Protists grow in damp, nutrient-rich environments and absorb food through their cell membrane, just like fungi. Like fungi, these organisms are heterotrophs that absorb nutrients from dead or decaying organisms. Unlike true fungi, fungus-like protists have centrioles and don’t have chitin in their cell walls like fungi. The fungus-like protists includes the cellular slime molds, the acellular slime molds, and the water molds.

Cellular Slime Molds spend most of their live as free-living organisms. They live in nutrients-rich soils so they can reproduce easily. When they don't have any food supplies, they send out chemical signal that attract other organisms. After a few days all the organisms join together in one huge colony that starts functioning as a single organism.

Like cellular slime molds, acellular slime molds begin their life cycle as amoeba-like organism. When they join together, their cells mutate to produce structures with many nucleuses. These are actually one single structure with many nuclei, and it’s called Plasmodia. After a while small fruiting bodies spring up from the plasmodium, the sporinga produces haploid spores that they use to reproduce.

Water molds live in dead or decaying organism in water. They can also live in land as plant parasites. Unlike true fungi, water molds have cell walls made of cellulose and produce motile spores. Water molds have both sexual and asexual phase in their life cycle.