IELTS Vocabulary ebook

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: 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: 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 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: Relating to or resembling a dog or dogs

Example sentences:

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: 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 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

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.

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:  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: (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.

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

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: 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 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: 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: 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: 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: 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: 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: 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.