Structural Organisation in Animals Practice Flashcards

Comprehensive vocabulary flashcards covering animal tissues, and the morphology and anatomy of the earthworm, cockroach, and frog as well as the frog.

Tissue

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

Organ System

A group formed when two or more organs perform a common function through their physical and/or chemical interaction.

Epithelium

A tissue with a free surface facing either body fluid or the outside environment, providing a covering or lining for parts of the body.

Squamous Epithelium

A single thin layer of flattened cells with irregular boundaries, commonly found in blood vessel walls and air sacs of lungs to form a diffusion boundary.

Cuboidal Epithelium

A single layer of cube-like cells found in ducts of glands and tubular parts of nephrons, specialized for secretion and absorption.

Columnar Epithelium

A single layer of tall and slender cells with nuclei located at the base, found in the lining of the stomach and intestine.

Ciliated Epithelium

Columnar or cuboidal cells bearing cilia on their free surface, used to move particles or mucus in a specific direction over the epithelium.

Exocrine Glands

Glands that secrete products like mucus, saliva, earwax, oil, and digestive enzymes through ducts or tubes.

Endocrine Glands

Ductless glands whose products, called hormones, are secreted directly into the fluid bathing the gland.

Tight Junctions

Specialized junctions that help to stop substances from leaking across a tissue.

Adhering Junctions

Junctions that perform cementing to keep neighbouring cells together.

Gap Junctions

Junctions that facilitate communication between cells by connecting the cytoplasm of adjoining cells for the rapid transfer of ions and molecules.

Connective Tissue

The most abundant and widely distributed tissue in complex animals, named for its function of linking and supporting other tissues or organs.

Fibroblasts

Cells in connective tissue that produce and secrete structural protein fibres called collagen or elastin.

Tendons

Dense regular connective tissues that attach skeletal muscles to bones.

Ligaments

Dense regular connective tissues that attach one bone to another.

Chondrocytes

Cells of cartilage enclosed in small cavities within the matrix they secrete.

Osteocytes

Bone cells present in spaces called lacunae.

Myofibrils

Numerous fine fibrils that compose long, cylindrical muscle fibres.

Neurons

The excitable unit of the neural system that exerts control over the body's responsiveness to changing conditions.

Neuroglia

Cells that protect and support neurons, making up more than one-half the volume of neural tissue in the body.

Morphology

The study of the form or externally visible features of an organism.

Anatomy

The study of the morphology of internal organs in animals.

Prostomium

A sensory lobe at the anterior end of an earthworm that serves as a mouth covering and a wedge to force open cracks in the soil.

Peristomium

The first body segment (buccal segment) of an earthworm which contains the mouth.

Clitellum

A prominent dark band of glandular tissue in mature earthworms covering segments $14-16$.

Typhlosole

An internal median fold of the dorsal wall of the earthworm intestine, present after segment $26$, which increases the effective area of absorption.

Nephridia

Segmentally arranged coiled tubules in earthworms that regulate the volume and composition of body fluids.

Sclerites

Hardened plates of the cockroach exoskeleton, consisting of dorsal tergites and ventral sternites.

Tegmina

The opaque, dark, and leathery forewings of a cockroach that arise from the mesothorax.

Malpighian Tubules

Yellow-coloured thin filamentous tubules in cockroaches that help in the removal of excretory products from the haemolymph.

Ommatidia

Hexagonal units (about $2000$ per eye) in the compound eyes of a cockroach that create mosaic vision.

Oothecae

Dark reddish to blackish brown capsules in which fertilised cockroach eggs are encased.

Poikilotherms

Animals, such as frogs, that do not have a constant body temperature and whose temperature varies with the environment.

Aestivation

The state of "summer sleep" taken by frogs in deep burrows to protect against extreme heat.

Hibernation

The state of "winter sleep" taken by frogs in deep burrows to protect against extreme cold.

Tympanum

A membranous structure in frogs that receives sound signals, serving as the ear.

Chyme

Partially digested food that passes from the stomach of a frog into the duodenum.

Cloaca

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