B4.2 SL / HL Flashcards
Niche
the role it plays in an ecosystem, including how it interacts with the environment and other organisms
spatial habitat
a region in an environment that is made up of multiple dimensions, each representing a characteristic of the environment
biotic factors
living organisms that make up an ecosystem, and they interact with each other and the environment to shape it
abiotic factors
non-living parts of an environment that affect living organisms and the functioning of ecosystems
Cellular respiration
a process that occurs in the cells of all living organisms that converts chemical energy from nutrients into adenosine triphosphate (ATP), which contains energy
Aerobic respiration
a chemical process that uses oxygen to create energy from carbohydrates and lipids
final electron acceptor
a molecule that receives the last electrons in an electron transport chain (ETC)
Anaerobic respiration
a process that produces energy without oxygen, using electron acceptors other than oxygen
Obligate anaerobes
microorganisms that can’t survive in the presence of oxygen, and are killed by normal atmospheric oxygen concentrations
hypoxia
a condition that occurs when there is a lack of oxygen in the body or in an environment
anoxia
a state of complete oxygen deprivation in an organ or tissue
Facultative anaerobes
an organism that can survive in both oxygen-rich (aerobic) and oxygen-poor (anaerobic) environments
Cyanobacteria
microscopic microorganisms, unicellular or multicellular oxygenic photoautotrophs, and Gram-negative prokaryotes
Green sulfur bacteria
anoxygenic phototrophic bacteria that grow only under strictly anoxic conditions
Purple bacteria
Gram-negative proteobacteria that are phototrophic, capable of producing their own food via photosynthesis
chlorophyll
a green pigment found in plants that absorbs red and blue light from sunlight, allowing plants to make their own food through photosynthesis
pigment
a colored material found in plant or animal cells that gives color to tissues, such as skin, eyes, and hair
Autotrophs
organisms that can produce their own food using energy from light or inorganic chemical reactions
Producers
organisms that make their own food and energy, and are the foundation of food webs in ecosystems
organic compounds
chemical compounds that contain carbon atoms covalently bonded to other elements, most commonly hydrogen, oxygen, or nitrogen
Heterotrophs
an organism that can’t produce its own food and instead gets nutrients from other sources, such as plants or animals
Consumer
an organism that cannot produce its own food and must eat other organisms for energy
holozoic nutrition
a type of heterotrophic nutrition that involves the consumption and internal processing of solid or liquid food by an organism
Herbivore
an animal that eats only plants, such as flowers, leaves, fruits, roots, or nectar
Carnivore
an organism that primarily eats meat, or the flesh of other animals
Omnivore
an organism that eats both plants and animals, as well as other materials like algae and fungi
Scavenger
an organism that consumes dead or decaying organic matter, such as rotting plant material or the remains of other animals
Ingestion
the process by which an organism consumes a substance
Endocytosis
a process in which cells absorb substances from outside the cell by engulfing them with their cell membrane
Digestion
the process of breaking down food into smaller molecules that the body can absorb and use for energy, growth, and repair
catabolic enzymes
proteins that speed up the breakdown of large molecules into smaller ones through biochemical reactions
Absorption
the process by which chemicals, such as nutrients, drugs, and toxicants, enter the bloodstream of an organism
Assimilation
the process by which living organisms convert food into chemicals, minerals, and vitamins that the body needs to function
Egestion
the process of removing undigested food or waste from an organism or cell+B35
Mixotrophic nutrition
a type of nutrition where organisms can use multiple sources of energy and carbon, or different modes of nutrition, to gain nutrients and carbon
Obligate mixotrophs
organisms that must use both heterotrophic and autotrophic methods of nutrition for growth and maintenance
Facultative mixotrophs
an organism that can use either heterotrophic or autotrophic means to grow and maintain itself, but only uses mixotrophy when necessary
decomposers
an organism that breaks down dead or decaying organisms and organic material for energy, carbon, and nutrients
Detritivores
organisms that consume dead and decaying plant and animal matter with internal digestion
Saprotrophs
organisms that feed on dead and decaying organic matter with external digestion
Domain
the highest order of life classification
Eukarya
any cell or organism that possesses a clearly defined nucleus
Bacteria
single-celledmicroorganismsthat lack a nuclear membrane, are metabolically active and divide by binary fission
Archaea
unicellular microorganisms with a prokaryotic cell structure and distinct genetic, biochemical, and physiological features
Extremophiles
organisms that can survive in environments that are considered extreme by humans
Photoautotrophic archaea
organisms that carry out photosynthesis. Using energy from sunlight, carbon dioxide and water are converted into organic materials
Chemosynthetic archaea
prokaryotic microorganisms that use chemosynthesis to create food, or sugars, from chemical reactions instead of photosynthesis
aphotic zone
the part of an ocean or lake where there is little to no sunlight
Methanogenic archaea
microorganisms that produce methane as a byproduct of their energy metabolism
mitogenesis
the process of cell division and proliferation, and the process of producing new mitochondria
Mastication
the process of chewing food, which is the first step in digestion
bolus
a ball-like mixture of food and saliva that forms in the mouth during chewing
Dentition
the study of the arrangement and structure of teeth in the mouth, including their number, type, and development
Incisors
the front teeth of mammals, including humans, that are used for cutting, biting, nibbling, and stripping food
Canines
the sharp pointy teeth in mammals’ mouths
Premolars
transitional teeth located between the canine and molar teeth
Molars
teeth located at the back of the mouth that are used for grinding food
Tusks
elongated teeth that grow continuously and extend beyond the mouth of some mammals
Rodent incisors
constantly growing rootless incisors that have a hard enamel layer on the front of each tooth and softer dentine behind
Diastema
a gap between the front and back teeth of an herbivore, and it helps with chewing and manipulating food
Carnassial teeth
specialized teeth found in carnivorous animals that are designed to slice through tough tissues
Hominidae
the taxonomic family of great apes and humans, which are known for their complex social behavior and intellectual abilities
frugivores
animals that eat fruit, seeds, flowers, and tubers as a primary part of their diet
Cellulose
the main substance found in plant cell walls and helps the plant to remain stiff and strong
Polysaccharide
long chains of carbohydrate molecules, composed of several smaller monosaccharides
cellulase
an enzyme that breaks down cellulose, a linear polysaccharide found in plant cell walls
mutual symbiosis
a type of symbiotic relationship where both species involved benefit from the interaction
Ruminants
mammals that have a complex stomach and digest plant-based food by fermenting it before digestion
Stylets
a hard, sharp, or hollow organ or appendage that some invertebrates use for piercing or feeding
Mandibles
a pair of mouthparts that function as jaws for gripping, biting, and cutting food
Tubular mouthparts
elongate, channelled along their surfaces and held together by hooks and spines to form a suckingtube
Coprophagy
a behavior where an animal reingests its own excreted feces
Phytotoxins
toxic substances that can harm plants, and can be produced by plants, microorganisms, or chemical reactions
Alkaloids
a group of naturally occurring chemical compounds that contain nitrogen and are often found in plants and fungi
Tannins
a class of astringent, polyphenolic biomolecules that bind to and precipitate proteins and various other organic compounds including amino acids and alkaloids
Predation
a biological interaction where one organism, the predator, kills and eats another organism, its prey
Camouflage
a defense mechanism that helps organisms hide their identity, location, and movement by blending in with their surroundings
Venom
the poisonous secretion of an animal, produced by specialized glands that are often associated with spines, teeth, stings, or other piercing devices
Neurotoxins
a substance that can alter the structure or function of the nervous system, causing neurotoxicity
Hemotoxins
an agent that alters blood flow (hemodynamics), destroys red blood cells (hemolysis), disrupts hemostasis (i.e., a coagulotoxin), or injures blood vessel walls (i.e., a vasculotoxin)
Cardiotoxins
chemicals that are toxic to the heart, causing muscle damage or heart electrophysiology dysfunction
Stalking
a hunting strategy used by predatory animals to stealthily follow and pounce on their prey
Ambush
a hunting strategy where an animal, known as an ambush predator, hides and waits for a prey to come within striking distance, then launches a sudden attack
Cooperative hunting
a hunting strategy where multiple animals work together to capture prey
Luring
a form of aggressive mimicrycharacterized by the waving or wriggling of the predator’s tail to attract prey
Batesian mimicry
a type of biological mimicry where a harmless organism mimics a dangerous one, to avoid being eaten by predators
Antimicrobial secretions
substances that are used to kill or inhibit the growth of bacteria, fungi, viruses, or other microbes
Nocturnal activity
the behavior of organisms that are active at night and sleep during the day
Thanatosis
a defensive behavior in which an animal appears dead to avoid being attacked by a predator
Mobbing
a behavior where prey approach, harass and sometimes attack a predator
palisade mesophyll
one or more layers of cells located directly under the epidermal cells of the adaxial leaf blade surface
Phototropism
the ability of plants to move or grow in response to light
Herbaceous plants
vascular plants that have green, soft stems and no permanent woody stems above ground
shrub layer
a layer of vegetation in a forest that’s made up of small woody plants and young trees, and is located between the canopy and the forest floor
Understory
the layer of vegetation that grows beneath the canopy of a forest or wooded area, made up of trees and shrubs
Canopy
the aboveground portion of a plant community or crop, made up of the crowns of individual plants
Lianas
woody vines that grow from the ground and climb up trees and other structures to reach sunlight
Epiphytes
plants that grow on other plants, or phorophytes, for physical support, but do not negatively affect the host plant
Fundamental niche
the ideal set of conditions that allow a species to survive and reproduce without competition or other limiting factors
Realized niche
the set of conditions actually used by given animal (pop, species), after interactions with other species (predation and especially competition) have been taken into account
intertidal zone
the area between the ocean and the shore that is exposed during low tide and underwater during high tide
Principle of competitive exclusion
an ecological principle that states that two species competing for the same limited resources cannot coexist in the same niche for long
Interspecific competition
a biological phenomenon that occurs when different species compete for the same resources, such as food, water, or space
paramecium
holotrichous ciliates, that is, unicellular organisms in the phylum Ciliophora that are covered with cilia
