21 - 30 van 33 bronnen weergeven

Light

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.

Onderwerp en thema
Form 1
Physics
Light
Sources of light
Type bron
Studieboeken
Taal
English
Uitgever
openstax
Publicatiedatum
2020
Schepper/Auteur
Openstax
Trefwoord
Electric Field
Electromagnetic Radiation
Magnetic Field
Maxwell's equations

Mitosis

Mitosis is how cells divide! Learn what happens in all the phases of mitosis: prophase, metaphase, anaphase, and telophase.

Onderwerp en thema
Form 1
Biology
Introduction to biology
Scientific processes in biology
Type bron
Video
Taal
English
Uitgever
Khan Academy
Publicatiedatum
2015
Schepper/Auteur
Sal Khan
Trefwoord
Mitosis
Cells

Molecular structure of DNA

Molecular structure of DNA. Nucleotide. Nitrogenous base, phosphate.

Onderwerp en thema
Form 1
Biology
Introduction to biology
Concept and terminologies of biology
Type bron
Video
Taal
English
Uitgever
Khan Academy
Publicatiedatum
2015
Schepper/Auteur
Sal Khan
Trefwoord
DNA
Molecular structure

Natural Selection

Outcomes:

  • Determine which mutations are favored by the selection agents of predators and food variety and which mutations are neutral.
  • Describe which traits change the survivability of an organism in different environments.
  • Experiment with environments which produce a stable population of bunnies, a population that dies out, and a population that takes over the world.
  • Track genes through multiple generations.
  • Compare how dominant and recessive genes get passed onto offspring.
Onderwerp en thema
Form 1
Biology
Introduction to biology
Concept and terminologies of biology
Type bron
Webinars
Taal
English
Uitgever
pHET Interactive Simulations
Publicatiedatum
No date
Schepper/Auteur
Amanda McGarry (lead design)
Chris Malley
Trefwoord
Natural selection

Overview of animal and plant cells

Overview of animal and plant cells. Topics include cell walls, vacuoles, chloroplasts, peroxisomes, lysosomes, mitochondria, etc.

Onderwerp en thema
Form 1
Biology
Cell structure and organisation
Plant and animal cells
Type bron
Video
Taal
English
Uitgever
Khan Academy
Publicatiedatum
2015
Schepper/Auteur
Sal Khan
Trefwoord
Animal cell
Plant cell

Phases of meiosis II

Meiosis is a process that creates sex cells (gametes) with half the number of chromosomes of the parent cell. Meiosis has two stages: meiosis I and meiosis II. In meiosis I, homologous chromosomes pair up and exchange genetic material (crossing over). In meiosis II, sister chromatids separate, creating four haploid cells.

Onderwerp en thema
Form 1
Biology
Introduction to biology
Concept and terminologies of biology
Type bron
Video
Taal
English
Uitgever
Khan Academy
Publicatiedatum
2015
Schepper/Auteur
Sal Khan
Trefwoord
Meiosis

Phases of meiosis I

How homologous chromosomes separate into two sets. Prophase I, metaphase I, anaphase I, and telophase I.

Onderwerp en thema
Form 1
Biology
Introduction to biology
Concept and terminologies of biology
Type bron
Video
Taal
English
Uitgever
Khan Academy
Publicatiedatum
2015
Schepper/Auteur
Sal Khan
Trefwoord
Meiosis

The Photoelectric effect

Photoelectric materials emit electrons when they absorb light of a high-enough frequency.

Onderwerp en thema
Form 1
Physics
Light
Sources of light
Type bron
Video
Taal
English
Uitgever
Khan Academy
Publicatiedatum
2021
Schepper/Auteur
Khan Academy
Trefwoord
electromagnetic radiation and matter
Photoelectric effect

pH Scale

Outcomes:

  • Determine if a liquid is acidic, basic, or neutral
  • Place acids or bases in relative order
  • Describe on a molecular scale, with illustrations, how the water equilibrium varies with pH
  • Determine concentration of hydroxide, hydronium and water at a given pH
  • Relate liquid color to pH
  • Predict (qualitatively and quantitatively) how dilution and volume will affect the pH and concentration of hydroxide, hydronium and water
Onderwerp en thema
Form 1
Biology
Introduction to biology
The biology laboratory
Type bron
Simulatie
Taal
English
Uitgever
pHET Interactive Simulations
Publicatiedatum
No date
Schepper/Auteur
Yuen-ying Carpenter (lead)
Trefwoord
pH
Dilution
Concentration
Acids
Bases

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.

Onderwerp en thema
Form 1
Biology
Cell structure and organisation
Concept of cells
Type bron
Video
Taal
English
Uitgever
Khan Academy
Publicatiedatum
2015
Schepper/Auteur
Sal Khan
Trefwoord
Cells