Generalized Eukaryotic Workshop Flashcards
Cell Theory
- all living things are made up of cells
- cells are basic units of life.
- cells come only from other cells
- cells carry genetic information in the form of DNA. This genetic material is passed from parent to daughter cell.
What is light microscopy?
light is focused on a specimen by a glass lens.
The image is then magnified for projection on the eye or photographic film.
Used to study live cells, use of certain dyes or preparations may kill live specimens.
What is electron microscopy?
a beam of electrons is used instead of light and electromagnets are used instead of glass lenses.
Preparation of the specimen kkills cells, so it can not be used to study living cells.
What is cell fractionation?
Cells whose cell membranes have been ruptured are centrifuged at various speeds for varying lenghts of time to separate diff sizes, densities and shapes.
What is freeze fracture?
technique used to study cell membranes and organelles.
A frozen specimen is fractures with a cold knife, producing a fracture plane that generally splits lipid bilayer membranes.
Describe the nucleus
Its where the genetic material is contained.
The nuclear envelope, separates the nucleus from the rest of the cell, consist of two cell membranes and is perforated by nuclear pores. The nuclear pores regulate the passage of large macro molecules into and out of the nucleus.
Describe the nucleolus
Dense structure within the nucleus, is the site of ribosomal RNA (rRNA synthesis. The nucleus is not surrounded by a membrane. After assembly, the ribosomal subunits are exported from the nucleus to the cytoplasm, where they will participate in protein synthesis.
Describe the mitochondria
site of aerobic respiration and ATP production within the cell. “The power house”. Bound by an outer and inner phospholipid bilayer membrane. Outer membrane has pores which selectively allow molecules to enter the cell depending their size. Th space between the inner and outer membrane is known as the intermembrane space. The inner membrane has many convolutions called cristae and also houses the proteins of the electron transport chain. The area bound by the inner membrane is known as the mitochondrial matrix.
What is the endosymbiotic hypothesis
Mitochondria developed from early prok cells that began symbiotic relationship with ancestor euk. The mitochondria provided energy and the host of the cell providing nutrients and protection for the exterior environment.
Describe ribosomes
synthesized in the nucleus and exported into the cytoplasm.
responsible for protein synthesis.
Each consist of a large and small subunit which consist of rRNA and proteins.
Proteins designed for the cytoplasm are synthesized by free ribosomes.
Proteins designed for insertion or secretion are synthesized by ribosomes bound to the ER.
Describe the Endoplasmic Reticulum
extensive network of membrane enclosed spaces in the cytoplasm. The interior is called the lumen.
Describe Smooth ER
has no ribosomes on outer surface. Involved in lipid synthesis and detoxification of drugs and poisons.
Describe rough ER
has ribosomes on outer surface. Involved in protein synthesis
Describe Golgi Aparatus
Proteins are modified and sorted based on the destination.
Modification to the proteins include the addition to sugar groups to proteins process called glycosylation.
Describe lysosomes
Contain hydrolytic enzymes involved in intracellular digestion. These enzymes break down protein, carbohydrates and nucleic acids. pH=5.
