When the chromatin is dispersed and not readily stainable, it is known as euchromatin. Euchromatin is prevalent in cells that are active in the transcription of many of their genes while heterochromatin is most abundant in cells that are less active or not active. The nucleus often contains one or more nucleoli that are spherical or oval bodies composed chiefly of ribonucleoproteins. Nucleoli are usually stained with basic dyes because of their high RNA content and are generally larger in cells that are actively participating in protein synthesis. The endoplasmic reticulum (ER) is a system of interconnected membranous sacs, channels, or cisternae in the cytoplasm.
What is the difference between prokaryotic cells and eukaryotic cells? What are the names for the two major groups of prokaryotes? both have a cell membrance on the outside and both have ribosomes but the eucaryotic only have membrane bound organelles. both can have the cell wal. euc.
| | | D) | All living organisms are composed of one or more cells. | | | | | | Feedback: Cell theory states: all living things are made of cells; cells basic units of structure and organization; cells arise only from previously existing cells. Most prokaryotic cells do not have specialized internal structures. | | 2 CORRECT | | A ____ contains polar and nonpolar ends, forming the plasma membrane. | | | A) | microtubule | | | B) | transport protein | |
All viruses have genes made from either DNA or RNA, long molecules that carry genetic information; all have a protein coat that protects these genes; and some have an envelope of fat that surrounds them when they are outside a cell. Fungi are diverse in terms of their shape, size & means of infecting humans. Fungi are eukaryotes, meaning that like parasites, their cells have a true nucleus and complex internal structures. They are most commonly found as environmentally resistant spores and molds, but can cause disease in humans in the forms of yeasts. Parasites are part of a large group of organisms called eukaryotes.
The nuclear membrane has a similar structure to the cell membrane but it contains gaps which allow protein to pass through. The nucleus controls almost all of the activities of the cell. Cytoplasm: The cytoplasm refers to anything which is inside the cell boundary and outside the nucleus. It is a semi-fluid material which is capable of flowing slowly. Many chemical reactions are carried out in the cytoplasm.
Golgi body: The Golgi body is an organelle found in most eukaryotic cells. The Golgi body has numerous functions, such as sorting and progressing protein. While present in the Golgi body, they are processed and sent throughout the cell. The Golgi body is also responsible for deciding which proteins are to be transported outside the cell. Cytoplasm: Cytoplasm is a jelly-like liquid which is made up mostly of water and salt.
Advanced biology week 1 assignment 1. Bacteria are prokaryotes because they are not living organisms; they are simply genetic information wrapped in a protein sheath and they cannot replicate without the help of a cell. 2. Coccus bacteria is bacteria have a spherical shape. In nature, these bacteria may exist as individuals cells or be grouped together.
Write a 400- to 600-word research report (about two double-spaced pages) evaluating the evidence that supports the endosymbiosis hypothesis for the origin of mitochondria and chloroplasts in eukaryotic cells. Provide at least two properly cited references in your research report. The endosymbiosis hypothesis, developed by Margulis (1970), suggests an explanation for the evolutionary origin of organelles, specifically mitochondria and chloroplasts, in eukaryotic cells. The many similarities between mitochondria and chloroplasts led biologists to wonder if they shared a common evolutionary origin, separate from the rest of the cell. These organelles are believed to have been absorbed in early pre-eukaryotic cells and ultimately developed a symbiotic relationship with the host cell over time.
In this lab, we used differential centrifugation to isolate mitochondria and nuclei from cauliflower. We also measure the rate at which a certain molecule is converted to another molecule and how much a given enzyme can convert at a given time. Then we will get three fractions and find out which fraction has the most mitochondria and which fraction has the purest mitochondria. Nuclei and mitochondria are both organelles that are found within most eukaryotic cells. The nucleus is enclosed by a double membrane nuclear envelope.
A gene very similar to that of a eukaryote which codes for a DNA polymerase is found inside of the virus T4, which infects bacteria, showing that this theory is possible. So, are viruses alive? Well, it depends on the scientist. A