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Biology
Definitions for grade 10 Biology unit
Term | Definition |
---|---|
Cells | The smallest unit that can peform the functions of life |
cell division | the process by which a parent cell divides into two identical daughter cells |
diffusion | is the movement of molecules from area where there is high concentration to area where there is low concentration of molecules |
organ | a combination of several types of tissue working together to perform a specific function |
tissue | a cluster of similar cells that share the same specialized structure and functions |
cancer | cells with abnormal genetic material that are dividing uncontrollably and can spread to other body parts |
mutagen | a substance or factor that can cause a mutation in DNA |
stem cell | an unspecialized cell that can produce various types of specialized cells |
tumour | an abnormal clump or group of cells |
cell specialization | the process by which cells develop from similar cells into those that have specific functions within a multicellular organism |
cell differentiation | a stage of development of a living organism during which specialized cells form |
xylem | vascular tissue that conducts water and minerals from the roots to the leaves |
phloem | vascular tissue that transports sap carrying the sugars produced through photosynthesis from the leaves to the rest of the plant |
meristematic stem cell | an unspecialized cell found in plants that gives rise to a specific specialized cell` |
gall | an abnormal growth of plant tissue caused by insects or micro-organisms |
dermal tissue | the outermost protective layer of a plant |
endoscopy | a technique for looking inside the body that involves inserting a tiny light and camera attached to a flexible tube into a body opening, such as the mouth or small incision |
mucus | protective secretions from the stomach wall that prevent the stomach lining from breaking |
gastric juices | digestive secretions from the stomach wall composed of hydrochloric acid and pepsin |
esophagus | a muscular tube between the pharynx and the stomach |
small intestine | organ between the stomach and the large intestine, where most digestion occurs |
alveoli | the tiny air sacs in the lungs where gas exchange occurs |
aorta | the main blood vessel carrying oxygenated blood from the heart to branch arteries that lead to the rest of the body |
valve | flexible fall of tissue that ensures one way flow of blood |
pulmonary artery | vessels that carries deoxygenated blood from the heart to the lungs |
cilia | microscopic, hair-like projections on epithelial cells that may secrete mucus and help to keep foreign particles out of the body |
leeuwenhoek microscopes | allowed people to see clear images of tiny organisms |
brightfieqld/ dark filed microscopes | placing a thing metal disc beneath the stage between the light source and the objective lens, converts a brightfield microscope to a darkfield microscop |
fluorescence microscope | requires that the specimen be treated with special fluorescent stains |
trasmissione electron microscope | beams electrons through a specimen. denser portions of the specimen allow fewer electrons to pass through and appear darker in the image |
phase contrast microscope | it emphasizes slight differences in a specimen's capacity to bend light waves, there by enhancing light and dark regions without using stains |
cytoplasm | fluid material inside of cell, it consists of cytosol (the liquid part) and many specialized organelles |
mitosis | the division of the nucleus into two identical nuclei is now complete |
cytokinesis | the divine of the rest of the cell (cytosol and organelles) |
benign tumour | tumour that remains in one place on the body (non cancerous) |
malignant tumour | tumour that is capable of spreading throughout the body (cancerous) |
cell suicide (apoptosis) | the cell breaks down and the cell contents are distributed for other cells to use |
hypertension | high blood pressure |
arteriosclerosis | thickening of the walls arteries which narrows the passage way for blood |
taproot | one main root that grows larger and thicker than the rest |
fibrous | spreads out horizontally near the surface of the soil |
system | a group of tissues and organs that perform a specific function |
root system | all the roots that lie below the ground |
shoot system | consists of the plant above ground and is responsible for support and performing photosynthesis |
cohesion | ability of water molecules to cling to each other. holds the water in the xylem together |
adhesion | tendency of water molecules to stick to the walls of xylem preventing water from flowing back down to the roots |