The main characteristics of animals are sexual reproduction, eukaryotic cells, movement, multicellularity and heterotrophy. Animal cells are differentiated and organized into tissues, except in sponges. Animal tissues serve specific functions, and they include muscle tissue, nervous tissue, connective tissue and epithelial tissue.Continue Reading
Animal cells are complex and have a membrane, nucleus and organelles, such as ribosomes, Golgi apparatus and mitochondria. They also contain DNA, which is organized into chromosomes. The eukaryotic nature of animals is not unique to them, because other organisms, such as plants, protists and fungi, are also eukaryotic.
Animal cells are also diploid in nature, meaning that they contain two sets of genetic material. Animals are also heterotrophs because they ingest other animals and plants to get the carbon they need for survival. They also depend on oxygen for the production of energy in their cells.
Sexual reproduction in animals entails the combination of male and female genetic material, which results in the creation of new offspring. However, sexual reproduction is not unique to animals because bacteria, fungi and flowering plants also undergo it. There are exceptions in movement because some animals, such as annelids, brachiopods, sponges, hydras and corals, stay in a fixed position for most of their life. The speed of movement also varies among animals. Movement is an important characteristic because it enables animals to capture prey, avoid predators and settle in new habitats.Learn more about Zoology
Although sexual reproduction is a more common method of reproduction among animals, a few species, such as starfish and sea anemones, produce offspring via asexual reproduction. Asexual reproduction, in contrast to sexual reproduction, does not require the mating of two parents to produce an offspring. This means that there is no fusion of gametes and, in turn, no exchange of genetic information from parents to the offspring.Full Answer >
The advantages of the coelom in animals include the fact that the coelom, a cavity filled with fluid around the organs, provides a hydrostatic skeleton to aid movement, and allows for more efficient circulation of nutrients and removal of wastes. True coelems come in two varieties: schizocoelems and enterocoelems.Full Answer >
The Phylum Sarcodina is comprised of protozoan, or sarcodines, that share several characteristics; sarcodines have long, trailing cytoplasm and use unique cytoplasmic feet, or extensions, called pseudopodia to facilitate movement. Sarcodines also use pseudopods to feed, and they reproduce either sexually or asexually, depending on the species.Full Answer >
The seven characteristics of living things are movement, respiration, sensitivity, growth, reproduction, excretion and nutrition. Biology students often remember these characteristics using the acronym MRS GREN.Full Answer >