Arthropod Classification: Classes, Characteristics, and Diversity
Diversity and Success of Arthropods
The most successful animals on the planet are the arthropods. They live on land, in the sea, and in the air, making up over three-fourths of all currently known living and fossil organisms—over 1 million species in all.
Arthropods exhibit a vast distribution, ranging from the deep sea to mountain peaks, and vary greatly in size, from the king crab with its 12-foot armspan to microscopic insects and crustaceans.
Key Characteristics of Phylum Arthropoda
- Arthropods
Four Key Areas of Second Language Acquisition Research
How Second Languages Are Acquired
There are four areas of investigation and debate among Second Language Acquisition (SLA) researchers that deserve special attention from English language teachers:
The Nature of Input
Input is what you receive: the amount of language you are exposed to. Learners receive input from ‘messages’ which contain language a little above their existing understanding and from which they can infer meaning. The hypothesis makes a distinction between acquiring a language and learning
Evolution of Special Education Concepts and Legislation in Spain
1. Historical Evolution of Special Education
1.1. General Precedents
Before the Middle Ages (Pre-15th Century)
Abnormalities often led to Infanticide. People were scared of those with differences and were highly superstitious. Parents of the child might feel shame. (It is still difficult today to accept that relatives have difficulties.) Furthermore, resources for support were nonexistent during this period.
The Middle Ages
Churches condemned individuals with abnormalities but often practiced exorcism,
Read MoreUnlocking Language Learning: Core Principles for Educators
Understanding Language Learning: Insights for Teachers
There are four key areas of investigation and debate among second language acquisition researchers that deserve special attention from English Language Teachers:
1. The Nature of Input
Input refers to what you receive, the amount of language you are exposed to. The Input Hypothesis posits that language is acquired when learners receive input from ‘messages’ which contain language slightly above their existing understanding, and from which they
Read MoreAdvanced Communication Systems for Hearing Impairment
Enhancing Communication for Deaf Individuals
The PC System: Visualizing Speech
The PC system is a visual aid for speechreading, designed to eliminate potential confusion points that may arise due to similar articulation. For instance, distinct phonemes like /m/, /p/, and /b/ have the same articulation point and are therefore perceived as identical through lip-reading alone. Furthermore, some phonemes are “invisible” (e.g., velar phonemes /k/, /g/, /x/).
The PC system allows phonemes that appear similar
Read MoreHookworm and Toxocara Infections
Hookworm (Cutaneous Larva Migrans)
Larvae of animal hookworms cause this condition in humans. Found in animal feces and contaminated soil, they penetrate human skin causing a crawling eruption. Humans are not the definitive host; larvae migrate aimlessly in tissues and do not complete their life cycle.
Causative Agents
- Ancylostoma caninum (dogs): More common in tropical and subtropical countries. Potential zoonosis: cutaneous larva migrans.
- Uncinaria stenocephala (dogs): Increased prevalence in Chile