Asteroids, comets and meteors
These three short online lessons discuss asteroids, comets and meteors.
These three short online lessons discuss asteroids, comets and meteors.
Plant cells have a cell wall in addition to a cell membrane, whereas animal cells have only a cell membrane. Plants use cell walls to provide structure to the plant. Plant cells contain organelles called chloroplasts, while animal cells do not. Chloroplasts allow plants to make the food they need to live using photosynthesis.
A force diagram is a useful tool to help us visualise forces acting on an object and gives us informa- tion about the object’s motion. We often use force diagrams when solving calculations involving the forces acting on an object.
Other objects in the solar system are discussed in this online textbook viz. asteroids, meteorites, comets and dwarf planets.
Overview of animal and plant cells. Topics include cell walls, vacuoles, chloroplasts, peroxisomes, lysosomes, mitochondria, etc.
Defining and comparing tension, weight, friction and normal forces using free body diagrams.