Structural Organisation in Animals: The Frog

This set of vocabulary flashcards covers the structural organization of animals with a focus on the morphology and anatomy of the frog, Rana tigrina.

Tissue

A group of similar cells along with intercellular substances that perform a specific function.

Organ system

Formed when two or more organs perform a common function by their physical and/or chemical interaction.

Division of labour

The way cells, tissues, organs, and organ systems split up work to contribute to the survival of the body as a whole.

Evolutionary trend

The discernable trend of increasing complexity observed in organ and organ systems.

Morphology

The study of form or externally visible features; in animals, this refers to the external appearance of the organs or parts of the body.

Anatomy

The study of the morphology of internal organs in animals.

Rana tigrina

The scientific name of the most common species of frog found in India.

Poikilotherms

Animals that do not have a constant body temperature and vary with the environment; also called cold blooded.

Camouflage

The ability of frogs to change their colour to hide from enemies.

Mimicry

The protective coloration used by frogs to blend into their surroundings to hide from enemies.

Aestivation

The period of 'summer sleep' when frogs take shelter in deep burrows during peak heat.

Hibernation

The period of 'winter sleep' when frogs take shelter in deep burrows during peak cold.

Nictitating membrane

A membrane that covers and protects the bulged eyes of a frog while in water.

Tympanum

A membranous structure that acts as an ear and receives sound signals.

Sexual dimorphism

The presence of physical differences between male and female frogs, such as vocal sacs and copulatory pads in males.

Cloaca

A small, median chamber used to pass faecal matter, urine, and sperms to the exterior.

Chyme

Partially digested food that is passed from the stomach to the duodenum.

Villi and microvilli

Numerous finger-like folds in the inner wall of the intestine that absorb digested food.

Cutaneous respiration

The process of breathing through the skin, occurring in water where dissolved oxygen is exchanged by diffusion.

Pulmonary respiration

The process of respiration carried out by the lungs while the frog is on land.

Pericardium

The membrane that covers the muscular, three-chambered heart of the frog.

Sinus venosus

A triangular structure that joins the right atrium and receives blood through the vena cava.

Conus arteriosus

A sac-like structure on the ventral side of the heart into which the ventricle opens.

Hepatic portal system

The special venous connection found in frogs between the liver and the intestine.

Renal portal system

The special venous connection found in frogs between the kidney and the lower parts of the body.

Nephrons

The structural and functional units of the kidney, also known as uriniferous tubules.

Ureotelic

A classification for animals like frogs that excrete urea as their primary nitrogenous waste.

Cranium

A bony structure, also called a brain box, that encloses the brain.

Foramen magnum

The opening through which the medulla oblongata passes to continue into the spinal cord.

Mesorchium

A double fold of peritoneum that adheres the testes to the upper part of the kidneys.

Bidder’s canal

A canal in the kidney that receives vasa efferentia and communicates with the urinogenital duct.

Tadpole

The larval stage of a frog that undergoes metamorphosis to become an adult.

Metamorphosis

The process of transition from the larval tadpole stage to the adult frog stage.