Biodiversity and natural selection
Patterns and processes of evolution. How evolution and natural selection are reflected in the similarities and differences of organisms.
Patterns and processes of evolution. How evolution and natural selection are reflected in the similarities and differences of organisms.
There are many different processes and phenomena that emit electromagnetic radiation. Humans have taken advantage of many of these processes to develop technologies that use electromagnetic radiation.
The beauty of a coral reef, the warm radiance of sunshine, the sting of sunburn, the X-ray revealing a broken bone, even microwave popcorn—all are brought to us by electromagnetic waves. The list of the various types of electromagnetic waves, ranging from radio transmission waves to nuclear gamma-ray (γ-ray) emissions, is interesting in itself.
Even more intriguing is that all of these different phenomena are manifestations of the same thing—electromagnetic waves (see Figure 15.1). What are electromagnetic waves? How are they created, and how do they travel? How can we understand their widely varying properties? What is the relationship between electric and magnetic effects? These and other questions will be explored.
An image that illustrates light reflecting off a plain mirror.
Food webs are models that demonstrate how matter and energy is transferred between producers, consumers, and decomposers as the three groups interact within an ecosystem. Transfers of matter into and out of the physical environment occur at every level. Decomposers recycle nutrients from dead plant or animal matter back to the soil in terrestrial environments or to the water in aquatic environments. The atoms that make up the organisms in an ecosystem are cycled repeatedly between the living and nonliving parts of the ecosystem.
The particle model of matter is one of the most useful scientific models because it describes matter in all three states. Understanding how the particles of matter behave is vital if we hope to understand science!
The model also helps us to understand what happens to the particles when matter changes from one state to another.
In this unit, you will explore the three phases of matter and then look at the properties and differences between them. You will explore their shape, volume, and kinetic energy.
Photoelectric materials emit electrons when they absorb light of a high-enough frequency.
In this unit you will learn about different materials by investigating and observing the behaviour of their properties. This will include learning about the differences between metals and non-metals; whether they are isolators or conductors of electricity and heat, whether they are magnetic, how dense they are and whether they are acidic or basic.
By the end of this course you will: