82 results found

Search Results for: primitive

Primitive

primitive Undeveloped or in early stages of development,... Read More

Nervous System

    THE is the most complicated and highly organized of the various systems which make up the human body. It is the... Read More

Abiogenesis

Definition noun plural: abiogeneses a·bi·o·gen·e·sis, eɪbaɪəʊˈdʒɛnəsɪs (1) The idea that primitive life... Read More

RNA-DNA World Hypothesis?

How did life start as we know it? In the scientific community, the "RNA World Hypothesis" has many adherents. Many believed... Read More

Cyanobacteria

Cyanobacteria Definition Cyanobacteria is a group of photosynthetic bacteria widely distributed in various aquatic habitats... Read More

Life

Life Definition Life is a characteristic of a living organism that distinguishes the latter from a dead organism or a... Read More

Protist

Protist Definition What is a protist? All protists are eukaryotes, i.e. organisms with a nucleus. However, they are... Read More

Nucleus

In cell biology, the nucleus is the large, membrane-bounded organelle that contains the genetic material in the form of... Read More

Monotreme

Definition noun (zoology) Any of the egg-laying mammals belonging to the taxonomic group, Monotremata Supplement The class... Read More

Synapsid

Any member of the Synapsida clade of animals is referred to as a synapsid. They are believed to have descended from the... Read More

Living things

Living Things Definition A living thing pertains to any organism or a life form that possesses or shows the characteristics... Read More

Geological Periods

Precambrian Times (Most Ancient) All time before life existed, Earth was still a volatile environment, though the origins... Read More

Endosymbiotic theory

A eukaryotic cell is distinct from a prokaryotic cell by the presence of membrane-bound cellular structures called... Read More

Fish

While insects and similar types of organisms strived to occupy land, the sea was teeming with life aiming to secure their... Read More

Epiblast

Definition noun (embryology) The outer (upper) ectodermal layer of the embryonic disc, closer to the amniotic cavity, and... Read More

Ribonucleic acid

Ribonucleic Acid Definition noun (uncountable), ribonucleic acids ri·bo·nu·cle·ic ac·id, raɪboʊnjuːkliːɪk... Read More

Primitive Animals

Incorrect taxonomic classifications deemed organisms to be either animals or plants, in the Plantae or Animalia kingdoms... Read More

Anaerobic respiration

Anaerobic Respiration Definition What is anaerobic respiration? Anaerobic (cellular) respiration is a respiratory process... Read More

Eukaryotic cells

Eukaryotic Cells Definition What is a eukaryotic cell? Eukaryotic cells refer to the cells of (or derived from) eukaryotes,... Read More

Embryo

An embryo refers to the early developmental stage of a multicellular organism that follows fertilization. This stage... Read More

Archaea

Archaea is a group of prokaryotic life forms distinct from bacteria forming a separate domain of life. They possess... Read More

Spontaneous generation

Definition noun plural: spontaneous generations The previously popular notion that living organisms arise or develop from... Read More

A New Theory on the Origin of Animal Multicellularity

Multicellular life, purportedly, started around 600 million years ago. From single-celled, certain organisms eventually... Read More

Flora

Flora in Roman history refers to flowers. Flora was considered the god of spring for the Roman empire. In ecology, flora is... Read More

Cilium

Cilia Definition Cilia are hair-like structures found on the surface of many types of cells, including some mammalian... Read More

Tree

“The biological diversity is plenty if you look around yourself a little closely; with an eye for life!” … People... Read More

Prosimian

Definition noun, plural: prosimians Any of the primitive, nocturnal primates, such as lemurs, lorisoids, haplorrhine... Read More

Dead Man Walking

Dead Man Walking: Wade Davis and the Secret of the Zombie Poison By Patrick D. Hahn Accepted on September 4, 2007 Twenty... Read More

Sieve cell

Definition noun, plural: sieve cells (botany) The main conductive cell in the phloem of the gymnosperms and... Read More

Animal

Animal Definition An animal (plural: animals) refers to any of the eukaryotic multicellular organisms of the biological... Read More

Human Reproduction

Terminology and Concepts Primary reproductive organs are called gonads - testes in the male and ovaries in the female.... Read More

Head kidney

Head kidney --> pronephros 1. The definitive excretory organ of primitive fishes. Synonym: head kidney. 2. In the embryos... Read More

Apocarpous gynoecium

Apocarpous gynoecium is comprised by the set of many simple pistils (consistig of only one carpel). Characteristic fruit for... Read More

Spermiogenesis

Spermiogenesis Definition Spermiogenesis is the stage of spermatogenesis wherein the spermatids differentiate into mature... Read More

Arthropods

There are over two million species of arthropods, who initially arrived on Earth in the middle of the Cambrian period.... Read More

Chondrichthyes

Definition noun A taxonomic class comprised of cartilaginous fish Supplement Chondrichthyes is taxonomic superclass of... Read More

Homo neanderthalensis

Definition noun Species of primitive human beings that lived between 28,000 and 300,000 years ago. Various specimens of... Read More

Binary fission

Binary Fission Definition What is binary fission? In biology, binary fission is a type of asexual reproduction where a... Read More

Red algae

Red Algae Definition The red algae belong to the phylum Rhodophyta, which literally was derived from the Greek word... Read More

Intercalary meristem

The basic structural framework of plants is composed of different types of tissues. Based upon the capacity to divide, the... Read More