Amniotic egg: An amniotic egg such as a chicken egg has a water impermeable membrane surrounding the embryo, which allows for the development of the embryo outside of the parent's body without causing danger to an unprotected embryo. Animals that carry amniotic eggs include some mammals like the platypus, (which is one of the only mammals to carry amniotic eggs) reptiles, amphibians and most birds.
Epithelial tissue: The epithelial tissue line organs and bodily cavities such as the mouth, and prevents pathogens from entering the body through the cavities. The mouth of a dog has many different kinds of bacteria obtained from scavenging the outdoors, that, if introduced to the bloodstream, could cause infection. The epithelial tissue prevents the bacteria from entering the bloodstream.
Pollen: Pollen is the male gametes of a seed plant. It often appears as a chalky powdery substance, which allows it to stick to the pollinators (anything that spreads the pollen) and therefore spread to other plants. All plants reproduce by spreading their pollen to other plants, which create seeds for new plants. The pollen lies on the spores of the plant which is the long stem like organ on the flower which emerges from the center of the blossom.
Pollinator: A pollinator is an insect or any type of vehicle such as wind, that transfers the pollen to the female gametes of another flower, so that seeds can be produced. Bees play a very important role in pollination; they land on the spores of the flower, and a sticky substance on their legs picks up the pollen, therefore allowing it to be transferred to another plant once the bee moves on.
Lichen: Lichen is formed by the mutualistic relationship between a fungus and a photosynthetic alga. It can live in some of the most extreme climates on earth and can grow on trees, rocks, cement, and exposed soil. Lichen can be used to determine the amount of air pollution (less lichen is seen in areas with more pollution), can be used in dyes and perfumes, and is even utilized in many traditional or homeopathic medicines.
Mutualism: Mutualism is a symbiotic relationship in which both participants benefit. Lichen is an example of a mutualistic relationship between two organisms: a fungus and a photosynthetic alga. The relationship between the two allows for the lichen to live in extreme environments without being harmed. There is no reason to believe that anything the lichen lives on is harmed by it.
Enzyme: An enzyme is important to the whole process of life. Enzymes are catalysts, which means they speed up chemical reactions. The saliva in the mouth produces an enzyme called amylase which helps break down food prior to digestion, and can even be referred to as the first step to digestion.
Heterotroph: A heterotroph is an organism that feeds off of other organisms or their by-products. A donkey relies off eating grass and other vegetation for its energy and nutrients.
Hydrophobic: Hydrophobic means repelling or having aversion to water. Oil is hydrophobic, and, as seen in the photo, can not be soluble with water. The oil and the water are separated. In the membrane of a cell, there is a phospholipid bilayer which consists of hydrophobic phosphate heads which regulate intake of materials into the cell.
Homeostasis: Homeostasis is the ability of an organism to maintain a stable internal temperature regardless of external conditions. Since a dog is not able to sweat, it pants when it gets hot to maintain its internal temperature and cool down when the weather is hot.
Genetically modified organism: A genetically modified organism such as corn has one acquired one or more genes that were artificially implanted. This is also known as a transgenic organism. Currently, there is much dispute over whether or not genetically engineering organisms is harmful to the organism itself or those who consume it.
Animal that has a segmented body: The division of some animal (and plant's) body into a series of repetitive segmented units. The head, thorax and abdomen are the three labels for most segmented organisms, which usually have three segmented parts to their bodies. Segmented bodies are found on insects such as spiders, ants, bees and other insects. Lobsters also have segmented bodies, which is said to improve mobility.
Histamine: A substance released by mast cells that causes blood vessels to dilate and become more permeable during the inflammatory response. This means that when it reaches an organisms blood stream or comes in contact with any internal part of an organism that is susceptible to allergy (immune over reaction), the organisms immune system will attempt to get rid of it. Common allergens are pollen, dust, and hay.
Population: A localized group of the same species that are capable of interbreeding and producing fertile offspring. The population of maple trees in New England are not scarce and can grow from 30-145 feet tall.
Parasitism: A symbiotic relationship between the parasite and the host in which the parasite benefits at the expense of the host by either living inside or outside (on) the host. Horse flies are common parasites in New England as are ticks, fleas, and mosquitoes.
Sporophyte: A sporophyte is a diploid generation of a plant or alga that has a double set of chromosomes. Any plant or alga that can sexually reproduce (or flowers) is considered a sporophyte.
Tropism: A growth response that results in the tending of whole plant organs toward stimuli owing to differential rates of cell elongation. A plant, if left to do so will grow and eventually lean toward the sun, where it gets its energy.
Bilateral symmetry: Characterizing a body with a plane down the center which divides the body into two equal halves. Most organisms are bilaterally symmetrical. A moth is an example of how both sides of the longitudinal plane are equal on an organism.
Cellulose: A structural polysaccharide of cell walls consisting of glucose monomers joined by glycosidic linkages. Cellulose is the most abundant organic polymer on earth. It is found in the cell walls of green plants, cotton, wood, and dried hemp.
ATP: An adenine containing nucleoside triphosphate that releases free energy when its phosphate bonds are hydrolyzed. ATP is made by the mitochondria in animal cells, and fuels muscle movement or activity (including the brain). When a moth prepares to fly, ATP will fuel the movement in the body to propel it forward.
Sarcomere: A sarcomere is the basic unit of a muscle. They are made of long fibrous proteins that slide past each other when the muscles contract and relax. Actin which forms the thin filament and myosin which forms the thick filament are important proteins that are part of the sarcomere. Myosin binds to ATP to gain energy for contraction.
Turgor pressure: Turgor pressure pushes the plasma membrane against the cell wall of a plant. It is caused by osmotic flow of water into the central vacuole which has a higher solute concentration. Normally this would be okay, but the cell membrane inhibits the water to even out, resulting in an enlarged cell. This can cause wilting in a plant.
Xylem: A transport tissue that transports nutrients and water from the soil to the plant. The best known xylem is wood.
Genetic variation within a population: Genetic variation is very important because it provides genetic material for natural selection. The variation of genes mutate and help with creating the most efficient organisms for the environment. Here, a horse and a pony stand together, but their genes were made to live in separate environments.
Clade: A group which may be an organism, a group or a species that includes an ancestral species and all its descendants. An insect or a rodent may be a clade but a gorilla is not, because a gorilla is branched off separately from its ancestors.
Connective tissue: Connects, separates and supports different tissues, bones or organs in the body. Connective tissue ensures smoothness and ease of movement, in fact is it vital for movement along with many other functions. A cat's stealth and coordination could not be achieved without healthy connective tissue.
Vestigial structures: Are structures that were once used on an organism, but the organism has evolved to live without it. It has little to no use to the organism and is more a historical remnant of a structure that once was. A vestigial structure on a human is the tail bone, and a vestigial structure on a dog is their thumb nail.
Cuticle layer of a plant: A protective film on the epidermal tissue of a plant leaf. It is a waxy nonpolar substance that protects against rain, weather and possible threats of predators.
Cephalization: An evolutionary trend, where nervous tissue starts to tend toward one end of the organism, thereby creating a head region with sensory organs. That proved to be very efficient, so the trend stuck, and now organisms (animals) have heads.
Hydrophilic: Refers to a molecule that is water soluble, or has an affinity for water. It has a tendency to interact or be dissolved by water or other polar substances. We have taken advantage of that by creating powdered drinks such as iced tea that dissolves in water and can be consumed without the consumer choking.
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