Animal Reproduction and Development

These flashcards provide vocabulary terms and definitions covering asexual and sexual reproduction, types of asexual reproduction, metamorphosis, animal development processes, and embryonic stages based on the lecture notes.

Asexual Reproduction

A type of reproduction involving one parent, resulting in offspring identical to the parent with low genetic variability.

Sexual Reproduction

A type of reproduction involving two parents, resulting in offspring that are a mix between parents with high genetic variabilty.

Binary fission

A type of asexual reproduction where a prokaryote cell divides into two identical cells, such as in Amoeba or paramecium.

Budding

A type of asexual reproduction where a new organism grows off the parent organism, as seen in Hydra.

Regeneration

A form of asexual reproduction where several body parts grow as new organisms, occurring in Star fish and Planaria.

Spore formation

A seed like process where parent organisms release spores which grow into new organisms, such as in Dandelions.

Vegetative propagation

A form of asexual reproduction where a new organism grows from the roots of the parent organism, found in Strawberry plants.

Parthenogenesis

A process where a female can produce an embryo without fertilizing an egg with sperm, seen in some lizards, bony fishes, and amphibians.

Metamorphosis

The changes in form or structure in an individual after hatching or birth, usually affected by hormones and involving physiology, biochemistry, and behavior.

Tadpole

An aquatic larval stage that transforms into a land-dwelling frog (class Amphibia).

Bilateral symmetry

The internal symmetry of a larva in starfishes and other echinoderms before they undergo metamorphosis.

Radial symmetry

The symmetry of an adult starfish or echinoderm following metamorphosis.

Fertilization

The first process of animal development after which internal fertilization can lead to three ways of producing offspring.

Cleavage

The second process of animal development involving the division of the first cell to many within a ball of the same volume.

Gastrulation

The third process of animal development that transforms a blastula with one layer of cells into a gastrula with multiple germ layers.

Organ formation

The final process of animal development involving the formation of specific tissues from the germ layers.

Oviparity (Oviparous)

Reproduction where fertilized eggs are laid outside the female’s body and develop using nourishment from the egg's yolk, as seen in most bony fish, many reptiles, and birds.

Ovoviviparity (Ovoviviparous)

Reproduction where fertilized eggs are retained in the female, and the embryo obtains nourishment from the yolk until they are hatched, as seen in some sharks and garter snakes.

Viviparity (Viviparous)

Reproduction where young develop within the female and receive nourishment through a placenta until being born alive, as seen in most mammals.

White Albumen

A tertiary membrane in hen eggs consisting of water and protein, arranged in three layers: inner less dense, middle dense, and outer less dense.

Shell Membrane

A double membrane formed of keratin in hen eggs where the two membranes are separated by an air space at the blunt end.

Shell

The outer covering of land animals' eggs formed of calcium carbonate and containing up to $7000$ minute pores.

Collagen

A proteinoids substance that fills the minute pores of the egg shell, which are $0.04 \text{ to } 0.05,mm$ in diameter.

Jelly Coat

A gelatinous covering surrounding amphibian eggs.

Mermaid's Purse

The rectangular egg case of some cartilaginous fishes, such as the dog-fish, which has four long twisted elastic filaments for attachment to sea weeds.

Morula

A solid ball consisting of $12 \text{ to } 32$ blastomeres produced during the division of the first cell.

Blastula

A hollow sphere of cells, typically consisting of $128$ cells, formed by the cleavage of the morula.

Blastomeres

Cells that result from the process of cleavage of the zygote; they are genetically equal and each can give rise to a new individual.

Blastocoel

The fluid-filled cavity contained within the blastula.

Blastoderm epithe

The true epithelium into which cells in the blastula stage arrange themselves.

Ectoderm

One of the three germ layers formed during gastrulation, which gives rise to the neural system.

Endoderm

One of the three germ layers formed during gastrulation, which gives rise to the alimentary canal.

Mesoderm

One of the three germ layers formed during gastrulation, which gives rise to somite's and the notochord.

Archenteron

The digestive cavity or gastrocoel formed during the gastrulation process.

Organogenesis

The formation of organs from the germ layers, including the neural system, somite's, notochord, and vertebrate axis.

Holoblastic cleavage

Total cleavage that occurs when the cleavage furrows divide the entire egg, such as in amphibians.

Meroblastic cleavage

Cleavage where segmentation occurs only in a small portion of the egg, resulting in a cap of cells on top of the yolk, as seen in reptiles and birds.

Vegetal pole

The yolk rich pole of a polarized egg.

Animal pole

The yolk poor pole of a polarized egg where the zygotic nucleus is generally displaced.

Isolecithal

A type of egg with sparse, evenly distributed yolk, found in sea urchins and mice.

Mesolecithal

A type of egg with a moderate amount of yolk that is often unevenly distributed, found in frogs.

Telolecithal (Discolecithal)

A type of egg with dense yolk concentrated at one end, found in birds and reptiles.

Centrolecithal

A type of egg where the yolk is concentrated at the middle of the egg, found in flies.

Transitional cleavage

An atypical cleavage that is neither typically holoblastic nor meroblastic but assumes a stage between the two.

Neurula

The developmental stage that follows the Gastrula stage.

Zygote

The initial stage of animal development resulting from fertilization before it enters cleavage.

Pseudo-podia

Structures pulled in by an Amoeba before its nucleus divides during binary fission.

Keratin

The material that comprises the double shell membrane in the egg of a hen.

Calcium carbonate

The chemical compound that forms the outer shell of land animals' eggs.

Somite's

Segments that arise from the mesoderm germ layer during the process of organogenesis.