Biology quicksheet

• Hypertonic environment: cell has a lower concentration of solutes; higher water potential than surrounding extracellular fluid.
• Osmosis: diffusion of water.
• An erythrocyte placed in a hypertonic solution would crenate, becoming distorted in shape.
• Hypotonic environment: cell has a higher concentration of solutes than the solution outside the cell which causes the cell to well.
• Isotonic environment: cell has equal concentration with the solution outside the cell.
• Membrane proteins act as enzymes and receptor sites; function for chemical transport, intercellular communication, cell-to-cell recognition, and attachment to the cytoskeleton and extracellular matrix.
• Formation and transport of vesicles: secretory proteins are assembled by the ribosomes on the rough ER which, in turn, extrudes them across the ER into its channels.
• Enzymes embedded in the smooth ER may chemically modify some of the proteins.
• Proteins pass through more channels to the Golgi body.
• Proteins are encapsulated in vesicles by the pinching together of membranes of the Golgi body.
• Vesicles then pass through the cytoplasm, fuse with the interior surface of the plasma membrane and release their contents to the exterior.
• Lymphocytes are a subclass of white blood cells that are divided into two types: B-lymphocytes and T- lymphocytes.
• B-lymphocytes secrete antibodies for humoral immune response, where it binds to the antigen and eventually destroys it.
• Deserts are sandy and receive less rainfall.
• Gametogenesis is the production of gametes, which includes fertilization, cleavage, gastrulation (formation of germ layers), organogenesis (development into different tissues and organs), growth and histological differentiation.
• Taiga is characterized by heavy snowfall and conifer forests.
• Dominant haploid gametophyte are mosses.
• Mitosis is a somatic cell divides to form to identical diploid daughter cells, with stages: Prophase, Metaphase, Anaphase, Telophase.
• Diplohaplontic life cycle is an alternation of generation (life cycle of plants).
• Antibody against A and B are prokaryotes that do not have a nuclear membrane, have their DNA exposed to the cytoplasmic environment, and are part of the Kingdom Monera which includes bacteria, blue-green algae, and reproduces through binary fission.
• Savannah is a grassland regional and seasonal rain.
• A biome is an ecological community dominated with distinctive plants and animals.
• Dominant diploid sporophyte are ferns, pine trees and common weeds.
• Meiosis is a cell division responsible for the formation of gametes or sex cells which results to four cells with half the ploidy number of the mother cell, divided into two stages: Meiosis I and Meiosis II.
• Tundra is cold with frozen undersoil.
• Atrioventricular node is the heart’s electrical system activated by the impulse caused by the SA node, passes impulses down to the bundle of His resulting in the ventricular systole.
• Sinoatrial node is found at the right atrium, sends impulses through the atria resulting in atrial systole, considered as the pacemaker of the heart.
• Haploid gametophyte is part of the plant life cycle having haploid nuclei, gives rise to sex cells that produce a diploid sporophyte after fusing.
• Cardiac cycle: Deoxygenated blood travels through the vena cava, the blood will flow through the right atrium, right ventricle and lungs and becomes oxygenated, then travel through the left atrium, left ventricle, aorta and to all the cells in the body.
• Estuary is part of a river (freshwater) joined with the sea (saltwater).
• Tropical rainforests are found in areas near the equator where rainfall is abundant and the dry season lasts for no more than a few months, making them the richest biome in terms of number of species.
• The sound of pumping of the heart is caused by the valves.
• Developmental biology is the study of the development of animals, including the processes involved in the transformation of a fertilized egg to a more complexed individual.
• The parasympathetic division rests the body and produces calm responses, increasing stomach contractions to promote digestion, narrowing the pupils of the eyes, and constricting the trachea.
• These stands eventually give way to Sitka spruce, joined later by hemlock, forming a taiga.
• Class Insecta include grasshoppers.
• During the process of Meiosis I and II, the primary oogonium divides the cytoplasm unevenly, producing a polar body, resulting in only one active cell.
• Germinal layers include the ectoderm, mesoderm, and endoderm, from which the different organs of the body are derived.
• Primary ecological succession begins in a lifeless area where soil has not yet formed, such as a new volcanic island or a rubble left behind by a retreating glacier.
• Insulin production involves cutting the insulin gene from human DNA with a restriction enzyme, combining it in a plasmid (secondary DNA), and inserting it into Escherichia coli.