Animal Classification and cell division

This flashcard set covers classification categories (Reptilia, Aves, Mammalia), taxonomic principles, and the biological processes and stages of Amitosis, Mitosis, and Meiosis cell divisions.

Class-Reptilia

A class of animals with dry skin covered in scales, crawling movement, and usually five-toed feet with claws; examples include the wall lizard, crocodile, and snake.

Class-Aves

Warm-blooded animals with bodies covered in feathers, possessing two wings, a beak, and light, strong bones containing air cavities; examples include the crow and magpie.

Air sacs

Structures present with the lungs in birds that assist in flight.

Class-Mammalia

Warm-blooded animals characterized by hair-covered bodies, a four-chambered heart, and mammary glands used by females to feed babies.

Heterodont

A characteristic of mammalian teeth where teeth have different shapes and perform different jobs.

Platypus

An exceptional mammal that lays eggs instead of giving birth to live babies.

Taxon

A unit of classification used to identify and organize the animal world; the seven major levels are Kingdom, Phylum, Class, Order, Family, Genus, and Species.

Vertebrata

Advanced animals whose notochord is replaced by a vertebral column made of hard vertebrae.

Chordata

A phylum under the kingdom Animalia consisting of animals with a notochord, nerve cord, and pharyngeal gill slits.

Germ layers

Cellular layers of the embryo that give rise to different organs.

Mantle

A structure that covers the soft body of molluscs.

Radial symmetry

A form applicable to organisms like starfish that can be divided into similar halves by more than two planes passing through one main axis.

Coelenteron

A cavity surrounded by the body wall that acts as both a digestive and circulatory system.

Coelom

The fluid-filled space between the body wall and the alimentary canal of a multicellular animal.

Haemocoel

A body cavity filled with blood that serves as part of the circulatory system.

Pest

A term used to describe harmful insects within the phylum Arthropoda.

Amitosis

Direct cell division occurring in bacteria, yeast, fungi, and amoeba where the nucleus and cytoplasm separate directly into two cells.

Mitosis

Equational division occurring in somatic cells where the nucleus and chromosomes divide once to produce two identical daughter cells.

Meiosis

Reduction division occurring in reproductive mother cells where the nucleus divides twice but chromosomes divide once, resulting in daughter cells with half the original chromosomes.

Meristematic tissue

Plant tissue found at the apex of branches and roots that increases in number through mitotic division.

Caryokinesis

The phase of cell division explicitly involving the division of the nucleus.

Cytokinesis

The phase of cell division involving the division of the cytoplasm.

Interphase

The intermediary stage or resting stage between two consecutive cell divisions where the nucleus prepares for division.

Prophase

The longest stage of mitosis where the nucleus enlarges, chromatin condenses into chromosomes, and each chromosome divides into two sister chromatids.

Centromere

The point where sister chromatids are joined together in a chromosome.

Spindle apparatus

A structure formed by protein fibers at the end of prophase that assists in separating chromosomes.

Metaphase

The stage of mitosis where all chromosomes line up at the equator of the spindle apparatus and appear shortest and thickest.

Anaphase

The stage of mitosis where centromeres split and daughter chromosomes move toward opposite poles, taking shapes like the English letters V, L, J, or I.

Telophase

The final stage of karyokinesis where daughter chromosomes reach opposite poles, chromatin networks reform, and nuclear membranes reappear.

Cell plate

A structure developed in plant cells during cytokinesis by the deposition of hemicellulose and other components on the plasmalema.

Cleavage furrow

A groove that appears on the surface of an animal cell during cytokinesis, which squeezes inward to complete cell division.