Displaying 1 - 7 of 7 Resources

Cell theory

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. 

Subject and Topic
Form 1
Biology
Cell structure and organisation
Concept of cells
Resource Type
Video
Language
English
Publisher
Khan Academy
Publication Date
2015
Creator/Author
Sal Khan
Keyword
Cells

Cells and organisms

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).

Subject and Topic
Form 1
Biology
Cell structure and organisation
Concept of cells
Resource Type
Video
Language
English
Publisher
Khan Academy
Publication Date
2022
Creator/Author
Khan Academy
Keyword
Cells

Horizontally Launched Projectile

How to solve for the horizontal displacement when the projectile starts with a horizontal initial velocity. We also explain common mistakes people make when doing horizontally launched projectile problems.

Subject and Topic
Form 2
Physics
Motion in a straight line
Equations of uniformly accelerated motion
Resource Type
Video
Language
English
Publisher
Khan Academy
Publication Date
2016
Creator/Author
David SantoPietro
Keyword
two dimensional motion
Projectile motion
Projectile motion graphs

Introduction to the cell

Introduction to the cell.

Subject and Topic
Form 1
Biology
Cell structure and organisation
Concept of cells
Resource Type
Video
Language
English
Publisher
Khan Academy
Publication Date
2017
Creator/Author
Sal Khan
Keyword
Cells

Logarithms

In this course you will learn:

  1. What logarithms are.
  2. How to apply the log laws.
  3. How to simplify logs.
  4. How to solve log equations.
Subject and Topic
Form 2
Mathematics
Logarithms
Laws of logarithms
Resource Type
Cursus
Language
English
Publication Date
2023

Ramp: Forces and Motion

  • Predict, qualitatively, how an external force will affect the speed and direction of an object's motion.
  • Explain the effects with the help of a free body diagram.
  • Use free body diagrams to draw position, velocity, acceleration and force graphs and vice versa.
  • Explain how the graphs relate to one another.
  • Given a scenario or a graph, sketch all four graphs.
Subject and Topic
Form 2
Physics
Motion in a straight line
Equations of uniformly accelerated motion
Resource Type
Simulatie
Language
English
Publisher
pHET Interactive Simulations
Publication Date
No date
Creator/Author
Sam Reid (Developer)
Keyword
Force
Velocity
Acceleration

Scale of cells

Even though molecules, proteins, viruses, and cells are all tiny, there are significant size differences between them. The diameter of a water molecule is roughly 0.28 nanometers. The diameter of the protein hemoglobin is roughly 5 nanometers. The diameter of the HIV virus is roughly 120 nanometers. A red blood cell is 6-8 micrometers.

Subject and Topic
Form 1
Biology
Cell structure and organisation
Concept of cells
Resource Type
Video
Language
English
Publisher
Khan Academy
Publication Date
2015
Creator/Author
Sal Khan
Keyword
Cells