Life Cycle, Processes & Properties, LEA-MER
None of us are born looking exactly the way that we do today; this is because humans, like other species, undergo a series of changes as they mature and age, in accordance with their biological life cycle. This process can look very different across different species. In many simple organisms and in higher animals, the life cycle is completed within a single generation, while in most plants, the life cycle is multigenerational.
Life Cycle, Processes & Properties Encyclopedia Articles By Title
Leaf blister
Leaf blister, worldwide disease of many woody plants and ferns caused by fungi of the genus Taphrina. Peach leaf......
leaf miner
leaf miner, any of a number of insect larvae that live and feed within a leaf. Leaf miners include caterpillars......
learning
learning, the alteration of behaviour as a result of individual experience. When an organism can perceive and change......
lecanemab
lecanemab, human monoclonal antibody used for the treatment of Alzheimer disease. Lecanemab clears away and blocks......
Legionnaire disease
Legionnaire disease, form of pneumonia caused by the bacillus Legionella pneumophila. The name of the disease (and......
Legume
Legume, fruit of plants in the pea family (Fabaceae). Most legumes are dehiscent fruits that release their seeds......
leishmaniasis
leishmaniasis, human protozoal infection spread by the bite of a sand fly (subfamily Phlebotominae). Leishmaniasis......
lens
lens, in anatomy, a nearly transparent biconvex structure suspended behind the iris of the eye, the sole function......
lens dislocation
lens dislocation, abnormal position of the crystalline lens of the eye. The dislocation, which may be congenital,......
leprosy
leprosy, chronic infectious disease that affects the skin, the peripheral nerves (nerves outside the brain and......
leptospirosis
leptospirosis, acute systemic illness of animals, occasionally communicable to humans, that is characterized by......
Lesch-Nyhan syndrome
Lesch-Nyhan syndrome, hereditary metabolic disorder affecting the central nervous system and characterized by incoordination,......
lesion
lesion, in physiology, a structural or biochemical change in an organ or tissue produced by disease processes or......
leukemia
leukemia, a cancer of the blood-forming tissues characterized by a large increase in the numbers of white blood......
leukocytosis
leukocytosis, abnormally high number of white blood cells (leukocytes) in the blood circulation, defined as more......
leukopenia
leukopenia, abnormally low number of white blood cells (leukocytes) in the blood circulation, defined as less than......
leukoplakia
leukoplakia, precancerous tumour of the mucous membranes, usually seen in the mouth or on the tongue or cheeks,......
leukorrhea
leukorrhea, flow of a whitish, yellowish, or greenish discharge from the vagina of the female that may be normal......
life cycle
life cycle, in biology, the series of changes that the members of a species undergo as they pass from the beginning......
life span
life span, the period of time between the birth and death of an organism. It is a commonplace that all organisms......
Lillie, Frank Rattray
Frank Rattray Lillie was an American zoologist and embryologist, known for his discoveries concerning the fertilization......
lipid storage disease
lipid storage disease, any of a group of relatively rare hereditary disorders of fat metabolism, characterized......
lips
lips, soft pliable anatomical structures that form the mouth margin of most vertebrates, composed of a surface......
List of Deadliest Diseases
Throughout history, certain diseases have left an indelible mark on humanity—claiming millions of lives, straining......
List of Female Animals Called Cows
The word cow may bring to mind a familiar farm animal, but in zoological terminology, the term has a much wider......
List of Most Contagious Diseases
Infectious diseases have played a powerful role in shaping human history and still affect lives today—from sweeping......
List of Tick-Borne Diseases
Tick-borne diseases are illnesses transmitted to humans and animals through the bite of an infected tick. Ticks......
List of Vaccine-Preventable Diseases
Vaccines are among the most effective tools available in modern medicine, offering protection against a wide range......
listeriosis
listeriosis, disease caused by the bacterium Listeria monocytogenes. The bacterium has been isolated from humans......
liver
liver, the largest gland in the body, a spongy mass of wedge-shaped lobes that has many metabolic and secretory......
liver cancer
liver cancer, any of several forms of disease characterized by tumors in the liver. Benign liver tumors remain......
Locomotion
Locomotion, in ethology, any of a variety of movements among animals that results in progression from one place......
Lorenz, Konrad
Konrad Lorenz was an Austrian zoologist and the founder of modern ethology, the study of animal behaviour by means......
Louis Pasteur’s Contributions to Science
Many people know Louis Pasteur for the process that bears his name—pasteurization. However, Pasteur made several......
louping ill
louping ill, viral disease mainly of sheep and red grouse, causing inflammation of the brain and spinal cord. The......
Lubbock, John, 1st Baron Avebury
John Lubbock, 1st Baron Avebury was a banker, influential Liberal-Unionist politician, and naturalist who successfully......
lucid dreaming
lucid dreaming, phenomenon of sleep in which one is aware that one is dreaming. During lucid dreaming, individuals......
lumbago
lumbago, pain in the lower (lumbar) portion of the back. Lumbago is considered by health professionals to be an......
lung cancer
lung cancer, disease characterized by uncontrolled growth of cells in the lungs. Lung cancer was first described......
lung congestion
lung congestion, distention of blood vessels in the lungs and filling of the alveoli with blood as a result of......
lung infarction
lung infarction, death of one or more sections of lung tissue due to deprivation of an adequate blood supply. The......
lung plague
lung plague, an acute bacterial disease producing pneumonia and inflammation of lung membranes in cattle, buffalo,......
lupus erythematosus
lupus erythematosus, an autoimmune disorder that causes chronic inflammation in various parts of the body. Three......
lycanthropy
lycanthropy, (from Greek lykos, “wolf ”; anthropos, “man”), mental disorder in which the patient believes that......
Lyme disease
Lyme disease, tick-borne bacterial disease that is named for the town in the U.S. state of Connecticut in which......
lymphangitis
lymphangitis, bacterial infection of the lymphatic vessels. The condition is caused by streptococcus or staphylococcus......
lymphedema
lymphedema, an abnormal condition in which poor function of the lymphatic system allows fluid to build up in the......
lymphocytic choriomeningitis
lymphocytic choriomeningitis, inflammation of the meninges (membranes covering the central nervous system) and......
lymphogranuloma venereum
lymphogranuloma venereum, infection of lymph vessels and lymph nodes by the microorganism Chlamydia trachomatis.......
lymphoma
lymphoma, any of a group of malignant diseases of the lymphatic system, usually starting in the lymph nodes or......
lysogeny
lysogeny, type of life cycle that takes place when a bacteriophage infects certain types of bacteria. In this process,......
Machiavellianism
Machiavellianism, the political theory of the Italian statesman and writer Niccolò Machiavelli (1469–1527), as......
macroglossia
macroglossia, enlargement of the tongue, due to overdevelopment of the muscle or the accumulation of material within......
macula lutea
macula lutea, in anatomy, the small yellowish area of the retina near the optic disk that provides central vision.......
macular degeneration
macular degeneration, group of blinding disorders that cause the gradual deterioration of the retina in the eye.......
maggot
maggot, soft-bodied grub that is the larva of many dipterous flies. About half of fly species produce larvae that......
magnesium deficiency
magnesium deficiency, condition in which magnesium is insufficient or is not utilized properly. Magnesium is a......
major depressive disorder
major depressive disorder, mental disorder characterized by persistent hopelessness, disinterest in and lack of......
major types of pollinators
Pollination is essential to the perpetuation of the vast majority of the world’s wild plants—and thus the perpetuation......
malaria
malaria, serious relapsing infection in humans, characterized by periodic attacks of chills and fever, anemia,......
Malformation
Malformation, in biology, irregular or abnormal structural development. Malformations occur in both plants and......
malnutrition
malnutrition, physical condition resulting either from a faulty or inadequate diet (i.e., a diet that does not......
mandibulofacial dysostosis
mandibulofacial dysostosis, a rare, genetic disorder, inherited as an autosomal-dominant trait and characterized......
mange
mange, skin disease of animals caused by mite infestations, characterized by inflammation, itching, thickening......
mania
mania, in psychiatric terminology, any abnormal or unusual state of excitement, as in the manic phase of bipolar...
maple syrup urine disease
maple syrup urine disease, inherited metabolic disorder involving leucine, isoleucine, and valine (a group of branch......
marasmus
marasmus, a form of protein-energy malnutrition occurring chiefly from inadequate intake of both protein and calories.......
marble bone disease
marble bone disease, rare disorder in which the bones become extremely dense, hard, and brittle. The disease progresses......
Marek’s disease
Marek’s disease, highly contagious, often fatal malignancy of chickens that affects the nerves and visceral organs......
Marfan syndrome
Marfan syndrome, rare genetic connective tissue disorder that affects most notably the skeleton, heart, and eyes.......
Marine bioluminescence
Marine bioluminescence, heatless light generated chemically by marine organisms. Bioluminescence is exhibited by......
Maroteaux-Lamy syndrome
Maroteaux-Lamy syndrome, uncommon hereditary metabolic disease characterized by dwarfism, hearing loss, and progressive......
masochism
masochism, a habit or practice of deriving sexual gratification from the infliction of pain or suffering on oneself.......
mast seeding
mast seeding, the production of many seeds by a plant every two or more years in regional synchrony with other......
mastitis
mastitis, inflammation of the breast in women or of the udder in sheep, swine, and cattle. Acute mastitis in women......
mastoiditis
mastoiditis, inflammation of the mastoid process, a projection of the temporal bone just behind the ear. Mastoiditis,......
maternal imagination
maternal imagination, idea that maternal thoughts during pregnancy are transmitted directly to the developing fetus,......
McArdle disease
McArdle disease, rare hereditary deficiency of the enzyme glycogen phosphorylase in muscle cells. In the absence......
McLaren, Dame Anne
Dame Anne McLaren was an English geneticist who pioneered fundamental advances in mammalian genetics and embryology......
Measles
Measles, contagious viral disease marked by fever, cough, conjunctivitis, and a characteristic rash. Measles is......
measuring worm
measuring worm, (family Geometridae), the larva of any of a large group of moths in the order Lepidoptera. Because......
Mechanoreception
Mechanoreception, ability of an animal to detect and respond to certain kinds of stimuli—notably touch, sound,......
media dependency
The term media dependency refers to the setting of engagement responses among individuals and a particular medium......
mediastinal emphysema
mediastinal emphysema, pocket of air surrounding the heart and central blood vessels contained within the mediastinum......
mediastinitis
mediastinitis, inflammation of the tissue around the heart, aortic artery, and entrance (hilum) to the lungs, located......
medicinal poisoning
medicinal poisoning, harmful effects on health of certain therapeutic drugs, resulting either from overdose or......
Mediterranean diet
Mediterranean diet, popular diet based on the eating patterns of people living in the Mediterranean region. It......
medullary thyroid carcinoma
medullary thyroid carcinoma, tumour of the parafollicular cells (C cells) of the thyroid gland. It occurs both......
megacolon
megacolon, massive enlargement and dilation of the large intestine (colon). The two main types of the syndrome......
meiosis
meiosis, specialized type of cell division in germ cells that consists of two successive nuclear divisions, producing......
melancholia
melancholia, formerly the psychological condition known as depression. The term now refers to extreme features......
Melanin
Melanin, a dark biological pigment (biochrome) occurring in the skin, hair, feathers, scales, eyes, and some internal......
melanoma
melanoma, a spreading and frequently recurring cancer of melanocytes, specialized skin cells that produce the protective......
melioidosis
melioidosis, a bacterial infection in humans and animals caused by Burkholderia pseudomallei (Pseudomonas pseudomallei).......
melorheostosis
melorheostosis, rare disorder of unknown cause in which cortical bone overgrowth occurs along the main axis of......
memory disorder
memory disorder, any of various conditions, including certain diseases, that affect the ability to remember. Disorders......
meningitis
meningitis, inflammation of the meninges, the membranes covering the brain and spinal cord. Meningitis can be caused......
menopause
menopause, permanent cessation of menstruation that results from the loss of ovarian function and therefore represents......
mental disorder
mental disorder, any illness with significant psychological or behavioral manifestations that is associated with......
- Introduction
- Anxiety, Depression, PTSD
- Genetics, Environment, Stress
- Personality Development, Trauma, Genetics
- Behavioral Etiology
- Schizophrenia, Symptoms, Treatment
- Mood Disorders, Symptoms, Treatment
- Anxiety, Panic, Phobias
- Dissociation, Amnesia, Identity
- Borderline, Symptoms, Treatment
- Eating Disorders, Anorexia, Bulimia
- Therapy, Medication, Support
- Psychotherapy, Treatment, Causes
- Deinstitutionalization, Treatment, Causes
- Antipsychotics, Treatment, Medication
- Psychotherapy, Treatment, Recovery
- Behavioral Psychotherapy
- Group Psychotherapy
mercury poisoning
mercury poisoning, harmful effects of various mercury compounds on body tissues and functions. Certain modern industrial......