Topic 1 Cells Flashcards
Define ‘Nutrition”
The intake and use of food and nutrients by organisms.
Define “metabolism”
The conversion of organic molecules in an organism
Define “Growth”
The increase of size* within an organism.
*size/mass/number of cells
Define “Response”
Response/Sensitivity/Irritability
A reaction an organism has due to a stimuli
Define “Homeostasis”
The regulations of the interior environment of an organism
Define “Reproduction”
Production of offspring
Define “Excretion”
The process by which an organism gets rid of metabolic wastes
Define “Cytoplasm”
The cytoplasm is a jelly-like substance between the nucleus and the cell membrane. Various cell organelles like ribosomes, mitochondria, endoplasmic reticulum, etc. are suspended in the cytoplasm. It helps in the exchange and storage of substances among cell organelles.
Define “Zygote”
The cell formed by the union of a male sex cell (a sperm) and a female sex cell (an ovum)
Define “Embryo”
An organism in the early stages of growth and differentiation, from fertilization to the beginning of the third month of pregnancy (in humans).
Define “Surface area to volume ratio”
The amount of surface area of an organism divided by its volume
Define “Emergent properties”
An emergent property is a property that a collection or complex system has, but which the individual members do not have.
Example: The heart can pump blood. It is made up of heart cells, but the heart cells individually are unable to pump blood.
Define “Tissue”
Tissue is a group of cells that have similar structure and that function together as a unit
Define “Cell Differentiation”
The process during which young, immature (unspecialized) cells take on individual characteristics and reach their mature (specialized) form and function.
Define “Gene Expression”
Gene expression is the process by which information from a gene is used in the synthesis of a functional gene product that enables it to produce end products, protein or non-coding RNA, and ultimately affect a phenotype, as the final effect.
Define “Diffuse”
Diffusion is the net movement of anything from a region of higher concentration to a region of lower concentration.
Define “Stargardt’s Disease”
Stargardt’s generally refers to a group of inherited diseases causing light-sensitive cells in the inner back of the eye (retina) to deteriorate, particularly in the area of the macula where fine focusing occurs. Central vision loss also occurs, while peripheral vision usually is retained.
Define “Stem Cell”
Stem cells are the body’s raw materials — cells from which all other cells with specialized functions are generated. No other cell in the body has the natural ability to generate new cell types
Define “Pluripotent Stem Cell”
A stem cell that can turn into any cell type other than totipotent stem cells (cannot form the placenta).
Define “Induced Pluripotent Stem Cell”
Induced pluripotent stem cells are a type of pluripotent stem cell that can be generated directly from a somatic cell.
Define “Embryonic Stem Cell”
Embryonic stem cells are pluripotent stem cells derived from the inner cell mass of a blastocyst, an early-stage pre-implantation embryo. Human embryos reach the blastocyst stage 4–5 days post fertilization, at which time they consist of 50–150 cells
Define “Adult Stem Cell”
Adult stem cells are undifferentiated cells, found throughout the body after development, that multiply by cell division to replenish dying cells and regenerate damaged tissues. Also known as somatic stem cells, they can be found in juvenile, adult animals, and humans, unlike embryonic stem cells.
Define “Blastocyst”
A structure formed in the early development of mammals. It possesses an inner cell mass (ICM) which subsequently forms the embryo
Define “Somatic Cell”
A somatic cell, or vegetal cell, is any biological cell forming the body of a multicellular organism other than a gamete, germ cell, gametocyte or undifferentiated stem cell.
Cell membrane
The cell membrane is a biological membrane that separates the interior of all cells from the outside environment which protects the cell from its environment. The cell membrane consists of a lipid bilayer, including cholesterols that sit between phospholipids to maintain their fluidity at various temperatures
Steroid
any of a large class of organic compounds with a characteristic molecular structure containing four rings of carbon atoms (three six-membered and one five). They include many hormones, alkaloids, and vitamins.
Embedded
fixed firmly and deeply in a surrounding mass; implanted.
Hydrophobic
tending to repel or fail to mix with water.
Hydrophilic
having a tendency to mix with, dissolve in, or be wetted by water.
Amphipathic
(of a molecule, especially a protein) having both hydrophilic and hydrophobic parts.
Phosphate head
A phosphate head is the “head” group of a phospholipid, the lipid that makes up the cell membrane lipid bilayer.
Hydrocarbon
In organic chemistry, a hydrocarbon is an organic compound consisting entirely of hydrogen and carbon. Hydrocarbons are examples of group 14 hydrides. Hydrocarbons are generally colourless and hydrophobic with only weak odours. Because of their diverse molecular structures, it is difficult to generalize further.
Phospholipid bilayer
The lipid bilayer is a thin polar membrane made of two layers of lipid molecules. These membranes are flat sheets that form a continuous barrier around all cells.
Integral proteins
An integral membrane protein is a type of membrane protein that is permanently attached to the biological membrane. All transmembrane proteins are IMPs, but not all IMPs are transmembrane proteins. IMPs comprise a significant fraction of the proteins encoded in an organism’s genome.
Peripheral proteins
Peripheral membrane proteins are membrane proteins that adhere only temporarily to the biological membrane with which they are associated. These proteins attach to integral membrane proteins or penetrate the peripheral regions of the lipid bilayer.
Cholesterol
Cholesterol is any of a class of certain organic molecules. Cholesterol is a sterol, a type of lipid. Cholesterol is biosynthesized by all animal cells and is an essential structural component of animal cell membranes. When chemically isolated, it is a yellowish crystalline solid.
