Over a million students use our free study notes to help them with their homework
Natural selection describes the selective pressure favouring those species with certain phenotypes (characteristics) which make them better suited to the environment than other species. Those with favoura...
Genetic information is stored in the nucleus as DNA. Humans have 46 molecules of DNA in each cell; each molecule known as a chromosome. When the cell is in interphase of the cell cycle, the DNA is in the ...
Gaseous exchange of oxygen and carbon dioxide (diffusion) occurs between the alveoli (tiny air sacs) and capillaries (microscopic blood vessels) inside the lung. Diffusion refers to the passive net moveme...
The electrical impulse that travels along a nerve, known in biology as an action potential, gets passed along to an adjacent nerve as a chemical signal. When an action potential reaches the end of a nerve...
Eukaryotic cells are larger and more complex than prokaryotic cells. The eukaryotic cell contains a nucleus, which contains genetic material in the form of linear chromosomes. However, prokaryotic cells c...
←
366
367
368
369
370
→
Internet Safety
Payment Security
Cyber
Essentials
Comprehensive K-12 personalized learning
Immersive learning for 25 languages
Trusted tutors for 300 subjects
35,000 worksheets, games, and lesson plans
Adaptive learning for English vocabulary
Fast and accurate language certification
Essential reference for synonyms and antonyms
Comprehensive resource for word definitions and usage
Spanish-English dictionary, translator, and learning resources
French-English dictionary, translator, and learning
Diccionario ingles-espanol, traductor y sitio de apremdizaje
Fun educational games for kids
