IELTS® Vocabulary Flashcard

Definition: A large semiaquatic reptile similar to a crocodile but with a broader and shorter head, native to the Americas and China

Example sentences:

• The zoo here is now playing host to a pair each of seamy crocodiles, alligators and caimans, giving the city dwellers a glimpse of some rare species.

Definition: A cold-blooded vertebrate animal of a class that comprises the frogs, toads, newts, salamanders, and caecilians.

Example sentences:

• Spadefoot toads are desert-dwelling amphibians that breed opportunistically in short lived pools filled by periodic rainfall.

Definition: As regards bodily structure:

Example sentences:

• This plant may be regarded as anatomically the most primitive of the Medulloseae.

Definition: The bodily structure of an organism:

Example sentences:

• Scientists believe that some animals with very different anatomies are related - for instance, the kangaroo and the platypus, and the hippo and whale

Definition: Either of a pair of long, thin sensory appendages on the heads of insects, crustaceans, and some other arthropods:

Example sentences:

• In these fossils, detail of legs, antennae, wings, and even small body hairs are preserved.

Definition: an animal without a back bone, with six or more jointed legs, a segmented body and a supporting structure on the outside

Example sentences:

• Arthropod biodiversity was on average one-third greater on organic farms than on conventional farms.

Definition: A bird’s horny projecting jaws; the horny projecting jaw of animals other than birds, for example a turtle or squid.

Example sentences:

• As a trombone player pulls in the slide to make a higher frequency sound by reducing the volume of the tube, so does a bird open its beak and pull back its head to reduce the volume of its vocal tract.

Definition: A box-like or dome-shaped structure in which bees are kept

Example sentences:

• The ideal places for establishing bee colonies were locations where the farm pesticide use was low, and where there were several beehives in the wild.

Definition: Of or relating to biology or living organisms

Example sentences:

• IBM has unveiled an ambitious initiative to develop technologies that share the basic biological abilities of living organisms.

Definition: Relating to or resembling a dog or dogs

Example sentences:

Definition: The larva of a butterfly or moth, which has a segmented body resembling a worm with three pairs of true legs and several pairs of leg-like appendages

Example sentences:

• Flying to several sites to deposit eggs is a strategy used by all moths and butterflies whose caterpillars must hide from predators.

Definition: A silky case spun by the larvae of many insects for protection as pupae

Example sentences:

• I saw a spider's web and an insect larva beginning to spin a cocoon.

Definition: Denoting animals whose body temperature varies with that of the environment (e.g. fish)

Example sentences:

• Crocodiles are cold-blooded creatures, and they keep their temperature constant by basking in the sun and staying in the water at night.

Definition: Of, relating to, or denoting the last period of the Mesozoic era, between the Jurassic and Tertiary periods

Example sentences:

• The Jurassic and Cretaceous together were the age of giant reptiles.

Definition: A large predatory semiaquatic reptile with long jaws, long tail, short legs, and a horny textured skin, using submersion and stealth to approach prey unseen. The crocodile has been extensively hunted for its valuable skin

Example sentences:

• Hunted extensively for their skins, large crocodiles are becoming increasingly rare.

Definition: A large predatory semiaquatic reptile of an order that comprises the crocodiles, alligators, caimans, and gharial

Example sentences:

• In other species, such as monitor lizards and crocodilians, the lungs are partitioned into chambers made up of an intricate net of support structures

Definition: An arthropod of the large, mainly aquatic group Crustacea, such as a crab, lobster, shrimp, or barnacle.

Example sentences:

• Marine scientists have found evidence of similar patterns among shoreline species like crabs, crustaceans and seaweed.

Ectotherms are animals depending mainly on external heat sources, and their body temperature changes with the temperature of the environment. The adjective is ectothermic

Example sentences:

• Because reptiles are ectothermic, the embryos of live-bearing females and the eggs of oviparous females deposited in the soil or other locations are subject to fluctuating temperatures.
• Tortoises are ectotherms because they rely on the environment to sustain their body temperature.

Definition: of animals having body temperature that varies with the environment

Example sentences:

• Many ectothermic species demonstrate behavioral thermoregulation following feeding in an attempt to increase body temperature.

An embryo is an animal that is developing either in its mother's womb or in an egg, or a plant that is developing in a seed. Example sentences: 

• Between the eighth week of development and birth a human embryo is called a foetus.
• Recent research on human embryos led to the discovery that a left-right asymmetry is evident before birth.

Definition: An animal that is dependent on or capable of the internal generation of heat.

Example sentences:

• A small endotherm must maintain a steady internal temperature and has a considerabe demand for respiratory oxygen.
• Birds are endotherms and maintain high body temperatures.
• Endotherms are animals that maintain a constant body temperature even when environmental temperatures fluctuate. In contrast, the environment regulates the body temperature of ectotherms and thus their metabolic rate tends to be lower than the metabolic rates of endotherms, which must maintain a high, constant body temperature.

Definition:  dependent on or capable of the internal generation of heat.

Example sentences:

• People, polar bears, penguins, most other birds, and mammals are endothermic animals.

Definition: A rigid external covering for the body in some invertebrate animals, especially arthropods

Example sentences:

• Lobsters, like all animals with exoskeletons, periodically shed their armor as they grow.

Definition: (Of an animal, especially a dog) make a low guttural sound of hostility in the throat

Example sentences:

• The dog growls at the bottom of the tree, trying to claw his way up.

Definition: An animal lacking a backbone, such as an arthropod, mollusk, annelid, coelenterate, etc. The invertebrates constitute an artificial division of the animal kingdom, comprising 95 percent of animal species and about 30 different phyla

Example sentences:

• During the breeding season they eat mostly insects and other invertebrates.

To luminesce is to shine or glow with light. Some types of jellyfish have the uncanny ability to luminesce underwater.

When some object gives off light, that light is called luminescence.

Things that glow in the dark like light bulbs, are luminescent. Other luminescent things include the stars in the night sky, glow worms, and certain glowing jellyfish and other sea creatures. When a living thing is luminescent, it's a phenomenon called bioluminescence.

Definition: A mammal of an order whose members are born incompletely developed and are typically carried and suckled in a pouch on the mother’s belly. Marsupials are found chiefly in Australia and New Guinea, and also in America.

Example sentences:

• In South America and Australia, however, marsupials continued to be an important group of land mammals.

Definition: Relating to or deriving from the metabolism of a living organism:

Example sentences:

• Endotherms are animals that maintain a constant body temperature even when environmental temperatures fluctuate. In contrast, the environment regulates the body temperature of ectotherms and thus their metabolic rate tends to be lower than the metabolic rates of endotherms, which must maintain a high, constant body temperature.

Definition: The natural colouring matter of animal or plant tissue:

Example sentences:

• Lycopene is a red pigment that occurs naturally in certain plant and algal tissues.

Definition: The natural colouring of animal or plant tissue

Example sentences:

• Increased pigmentation in animals, such as these spots, may be genetic, acquired, or associated with pigmented tumors.

Definition: Color (something) with or as if with pigment

Example sentences:

• According to my reference sources, albino birds are extremely rare in the wild, and they also tend to be attacked by the normally pigmented members of their flock.

Definition: A pocket-like abdominal receptacle in which marsupials carry their young during lactation.

Example sentences:

• Two situations are considered, internal development of the embryos in closed incubating, brood or marsupial pouches, and external development in eggs exposed to the external medium. This group includes all of the pouched animals, such as opossums, kangaroos, and Tasmanian devils.

Definition: any member of the group of animals that includes human beings, apes, and monkeys

Example sentences:

• Primate is an order of mammals such as humans, monkeys, ape, lemurs, bush babies and tarsiers. They are distinguished by the use of hands.

Definition: A single-celled microscopic animal of a group of phyla of the kingdom Protista, such as an ameba, flagellate, ciliate, or sporozoan.

Example sentences:

• They have been considered animals, protozoans, fungi or space aliens.

Definition: A cold-blooded vertebrate of a class that includes snakes, lizards, crocodiles, turtles, and tortoises. They are distinguished by having a dry scaly skin, and typically laying soft-shelled eggs on land

Example sentences:

• Several hunts organized by the city government over the past months turned up empty-handed, apparently since cold-blooded reptiles are not very active during the chillier months

Definition: The evolutionary process by which an action or behaviour pattern in an animal loses its original function but is retained for its role in display or other social interaction.

Example sentences:

• Footdrumming, as with other signals, probably originated by ritualization of older forms of behavior not associated with communication such as running and digging.

Definition: An animal that feeds on carrion, dead plant material, or refuse:

Example sentences:

• There were the small herbivores and scavengers and hunters scuttling in the undergrowth, hiding from the larger predators who occasioned down from the heights.

Definition: A slender, flexible limb or appendage in an animal, especially around the mouth of an invertebrate

Example sentences:

• With its radiant color and plantlike shape, the sea anemone looks more like a flower than an animal. More specifically, the sea anemone is formed quite like the flower for which it is named, with a body like a stem and tentacles like petals in brilliant shades of blue, green, pink, and red.

Definition: also called white ant

Example sentences:

• Some termites feed on the wood timber of houses, posing a danger as a roof or ceiling can collapse from the impact of their feeding.

Definition: A poisonous substance secreted by animals such as snakes, spiders, and scorpions and typically injected into prey or aggressors by biting or stinging

Example sentences:

• Snake venoms have different effects.

Definition: (Of an animal, especially a snake) secreting venom; capable of injecting venom by means of a bite or sting

Example sentences:

• Anytime you receive a bite from a venomous snake, it's a very dangerous encounter

Definition: An animal of a large group distinguished by the possession of a backbone or spinal column, including mammals, birds, reptiles, amphibians, and fishes

Example sentences:

• For that reason the earliest terrestrial vertebrates did not come equipped with an occiput, as we understand the term.