cell biology basic idea
Cell Membranes membranes are fluid, with components that move, change, and perform vital physiological roles as they allow cells to communicate with each other and their environment.
membranes are fluid, with components that move, change, and perform vital physiological roles as they allow cells to communicate with each other and their environment.
membranes also are important for regulating ion and molecular traffic flow between cells,and that defects in membrane components lead to many significant diseases.
Cell Signaling living organisms constantly receive and interpret signals from their environment. Cells of multi-cellular organisms also receive signals from other cells, including signals for
cell division and differentiation.
. Signals can come in the form of light, heat, water, odors, touch, or sound. Cells of multi-cellular organisms also receive signals from other cells, including signals for cell division and differentiation. The majority of cells in our bodies must constantly receive signals that keep them alive and functioning. All organisms also have
Signaling systems that warn of the presence of pathogens, leading to a protective response.
The key
concept is that the many signaling systems of
biology have very similar or related steps. The same signaling system can lead to very different responses in different cells or different organisms. Studies of the mechanisms of cell signaling are leading to new understanding of many diseases, and to new strategies for therapy.
The Cell Cycle & Mitosis the events that occur in the cell cycle and the process of
Mitosis that divides the duplicated genetic material creating two identical daughter cells.
Mitosis is nuclear division plus cytokinesis, and produces two identical daughter cells during prophase, prometaphase, metaphase, anaphase, and telophase. Interphase is often included in discussions of mitosis, but interphase is technically not part of mitosis, but rather encompasses stages G1, S, and G2 of the cell cycle.
Meiosis the events that occur in process of gametogenesis that takes place to produce our gametes.
Diploid set for humans; 2n = 46 Autosomes; homologous chromosomes, one from each parent (humans = 22 sets of 2) Sex chromosomes (humans have 1 set of 2) Female-sex chromosomes are homologous (XX) Male-sex chromosomes are non-homologous (XY)
Prokaryotes, Eukaryotes, & Viruses the cells that make up all living systems, their organelles, and the differences between living cells and viruses.
The cell is a unit of organization Cells are classified by fundamental units of structure and by the way they obtain energy. Cells are classified as prokaryotes or eukaryotes, which will be covered in more detail in the next two pages of this tutorial. Living things are classified in six kingdoms based on structure. Within prokaryotes, which appeared 3.5 billion years ago, are the kingdoms Monera (Eubacteria) and Archaea. Within eukaryotes, which evolved 1.5 billion years ago, are the kingdoms Protista, Plantae, Fungae, Animalia. Cells are also defined according the need for energy. Autotrophs are "self feeders" that use light or chemical energy to make food. Plants are an example of autotrophs. In contrast, heterotrophs ("other feeders") obtain energy from other autotrophs or heterotrophs. Many bacteria and animals are heterotrophs.
Multicellular Organisms Multicellular organisms are created from a complex organization of cooperating cells. There must be new mechanisms for cell to cell communication and regulation. There also must be unique mechanisms for a single fertilized egg to develop into all the different kinds of tissues of the body. In humans, there are 1014 cells comprising 200kinds of tissues!
The Cytoskeleton the
Cytoskeleton acts both a muscle and a skeleton, and is responsible for cell movement, cytokinesis, and the organization of the organelles within the cell. The cytoskeleton is unique to eukaryotic cells. It is a dynamic three-dimensional structure that fills the cytoplasm. This structure acts as both muscle and skeleton, for movement and stability. The long fibers of the cytoskeleton are polymers of subunits. The primary types of fibers comprising the cytoskeleton are microfilaments, microtubules, and intermediate filaments.
More abstracts about the cell biology