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Understanding the structure of a muscle cell

Patterns and processes of evolution. How evolution and natural selection are reflected in the similarities and differences of organisms. 

Introduction to cell theory--the idea that 1) all living things are made of one or more cells, 2) cells are the basic unit of life and 3) all cells come from other cells. Explore the roles that Hooke, Leeuwenhoek and others played in developing cell theory.

Hooke and Leeuwenhoek were two of the first scientists to use microscopes to study the microscopic world of cells. Hooke coined the term "cell" after observing the tiny compartments in cork, while Leeuwenhoek discovered a variety of living creatures in pond water, blood, and other samples. They contributed to the cell theory by suggesting that cells are the fundamental units of life and structure, and that all living things consist of one or more cells that originate from other cells by division. 

All living things are made up of cells, which is the smallest unit that can be said to be alive. An organism may consist of one single cell (unicellular) or many different numbers and types of cells (multicellular).

• Determine the variables that affect the strength and direction of the electric field for a static arrangement of charges.
• Investigate the variables that affect the strength of the electrostatic potential (voltage).
• Explain equipotential lines and compare them to the electric field lines.
• For an arrangement of static charges, predict the electric field lines. Verify the prediction using vector addition.

These videos look at how to compare decimals.

Video 1: Construction of a circle when its radius is known
Video 2: Examples of how to construct a circle
Video 3: Common mistakes made when constructing a circle

Video 1: How to construct a line segment
Video 2: Examples of constructing different line segments
Video 3: Common mistakes made when constructing a line segment

Video 1: What are perpendiculars and perpendicular bisectors and how to construct them
Video 2: How to draw a perpendicular and perpendicular bisector using a ruler and a compass
Video 3: Examples related to the construction of perpendiculars and perpendicular bisectors on a line segment
Video 4: Common mistakes made when constructing perpendiculars and perpendicular bisectors

This online activity provides you with exercises on converting fractions to decimals.