Types of cell and organisms
Answers
Answered by
0
Cells are of two types:eukaryotic, which contain anucleus, and prokaryotic, which do not. Prokaryotes aresingle-celled organisms, whileeukaryotes can be eithersingle-celled or multicellular.
Answered by
5
Prokaryotic Cells
The simplest type of cells were most likely the first type of cells that formed on Earth. These are called prokaryotic cells. All prokaryotic cells have a cell membrane surrounding the cell, cytoplasm where all of the metabolic processes happen, ribosomes that make proteins, and a circular DNA molecule called a nucleoid where the genetic information is held. The majority of prokaryotic cells also have a rigid cell wall that is used for protection. All prokaryotic organisms are unicellular, meaning the entire organism is only one cell.
Prokaryotic organisms are asexual, meaning they do not need a partner to reproduce. Most reproduce through a process called binary fission where basically the cell just splits in half after copying its DNA. This means that without mutations within the DNA, offspring are identical to their parent.
All organisms in the taxonomic domains Archaea and Bacteria are prokaryotic organisms. In fact, many of the species within the Archaea domain are found within hydrothermal vents. It is possible they were the first living organisms on Earth when life was first forming.
Eukaryotic Cells
The other, much more complex, type of cell is called the eukaryotic cell. Like prokaryotic cells, eukaryotic cells have cell membranes, cytoplasm, ribosomes, and DNA. However, there are many more organelles within eukaryotic cells. These include a nucleus to house the DNA, a nucleolus where ribosomes are made, rough endoplasmic reticulum for protein assembly, smooth endoplasmic reticulum for making lipids, Golgi apparatus for sorting and exporting proteins, mitochondria for creating energy, a cytoskeleton for structure and transporting information, and vesicles to move proteins around the cell.
Some eukaryotic cells also have lysosomes or peroxisomes to digest waste, vacuoles for storing water or other things, chloroplasts for photosynthesis, and centrioles for splitting the cell during mitosis. Cell walls can also be found surrounding some types of eukaryotic cells.
Most eukaryotic organisms are multicellular. This allows the eukaryotic cells within the organism to become specialized. Through a process called differentiation, these cells take on characteristics and jobs that can work with other types of cells to create an entire organism. There are a few unicellular eukaryotes as well. These sometimes have tiny hair-like projections called cilia to brush away debris and may also have a long thread-like tail called a flagellum for locomotion.
The third taxonomic domain is called the Eukarya Domain. All eukaryotic organisms fall under this domain. This domain includes all animals, plants, protists, and fungi. Eukaryotes may use either asexual or sexual reproductiondepending on the organism's complexity. Sexual reproduction allows more diversity in offspring by mixing the genes of the parents to form a new combination and hopefully a more favorable adaptation for the environment.
The simplest type of cells were most likely the first type of cells that formed on Earth. These are called prokaryotic cells. All prokaryotic cells have a cell membrane surrounding the cell, cytoplasm where all of the metabolic processes happen, ribosomes that make proteins, and a circular DNA molecule called a nucleoid where the genetic information is held. The majority of prokaryotic cells also have a rigid cell wall that is used for protection. All prokaryotic organisms are unicellular, meaning the entire organism is only one cell.
Prokaryotic organisms are asexual, meaning they do not need a partner to reproduce. Most reproduce through a process called binary fission where basically the cell just splits in half after copying its DNA. This means that without mutations within the DNA, offspring are identical to their parent.
All organisms in the taxonomic domains Archaea and Bacteria are prokaryotic organisms. In fact, many of the species within the Archaea domain are found within hydrothermal vents. It is possible they were the first living organisms on Earth when life was first forming.
Eukaryotic Cells
The other, much more complex, type of cell is called the eukaryotic cell. Like prokaryotic cells, eukaryotic cells have cell membranes, cytoplasm, ribosomes, and DNA. However, there are many more organelles within eukaryotic cells. These include a nucleus to house the DNA, a nucleolus where ribosomes are made, rough endoplasmic reticulum for protein assembly, smooth endoplasmic reticulum for making lipids, Golgi apparatus for sorting and exporting proteins, mitochondria for creating energy, a cytoskeleton for structure and transporting information, and vesicles to move proteins around the cell.
Some eukaryotic cells also have lysosomes or peroxisomes to digest waste, vacuoles for storing water or other things, chloroplasts for photosynthesis, and centrioles for splitting the cell during mitosis. Cell walls can also be found surrounding some types of eukaryotic cells.
Most eukaryotic organisms are multicellular. This allows the eukaryotic cells within the organism to become specialized. Through a process called differentiation, these cells take on characteristics and jobs that can work with other types of cells to create an entire organism. There are a few unicellular eukaryotes as well. These sometimes have tiny hair-like projections called cilia to brush away debris and may also have a long thread-like tail called a flagellum for locomotion.
The third taxonomic domain is called the Eukarya Domain. All eukaryotic organisms fall under this domain. This domain includes all animals, plants, protists, and fungi. Eukaryotes may use either asexual or sexual reproductiondepending on the organism's complexity. Sexual reproduction allows more diversity in offspring by mixing the genes of the parents to form a new combination and hopefully a more favorable adaptation for the environment.
Similar questions
Computer Science,
6 months ago
Social Sciences,
6 months ago
Computer Science,
6 months ago
Math,
1 year ago