Cell and Cell cycle Flashcards
(44 cards)
-functional unit of living organisms
-An organism can be unicellular or multicellular
Cell
the process by which cells assume specialized structure and function
Differentiation
other name for Plasma membrane
Plasmalemma
- Function: Dynamic interface with the external environment
- For transfer of nutrient and metabolites
- Attachment of the cell to adjacent cells and extracellular matrix
- Communication with the external environment
Plasma membrane
hydrophilic (water loving), head, glycerol conjugated to a nitrogenous compound
Polar
hydrophobic (water hating), tail, two-long chain fatty acids
Non Polar
- Largest organelles in the cell
- Control center of the cell, containing
the “blueprint” - Composition:
DNA (20% of its mass)
Protein (nucleoprotein) Some Ribonucleic acid (RNA)
Nuclear RNA includes mRNA, tRNA, and rRNA
Nucleus
- Heterogenous structures with electron- dense and electron-lucent (light) areas
Nuclei
electron-lucent nuclear material that is active in RNA synthesis
Euchromatin
dense areas (tightly- coiled inactive chromatin)
Heterochromatin
- Sites of ribosomal RNA synthesis and ribosome assembly
- Ribosomal RNA and proteins, synthesized in the cytoplasm and imported back into the nucleus, are assembled into subunits
- The subunits then passed backed to the cytoplasm to aggregate the complete ribosomes.
Nucleolus
Cytoplasmic organelles are suspended in fluid medium called
Cytosol
provides structural support for the cells and its organelles, as well as providing mechanism for transfer of materials within the cell and movement of the cell itself.
Cytoskeleton
-made up of many linked monomers of a protein called actin, combined in a structure that resembles a double helix.
❑also known as actin filaments.
❑come together to form linear, rod-like bundles, but they can also form branching networks with the assistance of proteins that anchor new side branches.
❑Actin is a key part of the cytoskeleton and is found in virtually all types of eukaryotic cells.
Microfilaments
Movement of a motor protein called
Myosin
❑ One familiar protein that forms intermediate filaments is keratin, a fibrous protein found in hair, nails, and skin
❑A type of cytoskeletal element made of multiple strands of fibrous proteins wound together.
Intermediate filaments
❑the largest of the three types of cytoskeletal fibers - diameter of about 25 nm.
❑made up of tubulin proteins arranged to form a hollow, straw-like tube, and each tubulin protein consists of two subunits, α- tubulin and β-tubulin.
Microtubules
❑A structure found near the nucleus of animal cells, serves as a microtubule-organizing center.
Centrosomes
- They play a vital role in facilitating the reproduction of cells.
- They engage in the arrangement of mitotic spindles during cell division.
- It aids in cytokinesis.
- It organises the microtubules in the cytoplasm.
- They regulate the position of the nucleus and other organelles in the cell
Centrioles
long, hair-like structures that extend outward from the plasma membrane and are used to move an entire cell
Flagella
resemble flagella, but are shorter and can generally be divided into two different categories
Cilia
plays an important role in the modification of proteins and synthesis of lipids.
ER
Sacs that is in ER
Cisternae
❑It produces lipids, including phospholipids, cholesterol and steroids, and glycolipids (lipids with carbohydrate groups attached).
❑Enzymes that assemble these lipids manufacture their products on the smooth ER’s membrane, where hydrophobic molecules can be sheltered from the surrounding watery (hydrophilic) environment.
❑Detoxification: substances like drugs and toxic byproducts of metabolism are modified by enzymes that reside in the smooth ER, making them more water-soluble and easier for the body to remove.
❑storage tank for calcium ions, which function in cell signalling.
Smooth ER
