21 - 30 van 30 bronnen weergeven

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 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

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

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

Skeletal structure and function

Skeletons support and protect our bodies. Bugs have exoskeletons outside their bodies, while humans have endoskeletons inside. Our bones are in axial (skull, ribcage, spine) and appendicular (arms, legs) groups. Bone marrow makes blood cells; more specifically, red marrow makes blood and yellow marrow stores fat. 

Onderwerp en thema
Form 1
Biology
Introduction to biology
Concept and terminologies of biology
Type bron
Video
Taal
English
Uitgever
Khan Academy
Publicatiedatum
2014
Schepper/Auteur
Tracy Kim Kovach
Trefwoord
Skeletal structure

Sura za Meiosisi - Phases of Meiosis

The phases of Meiosis.

Onderwerp en thema
Form 1
Biology
Introduction to biology
Scientific processes in biology
Type bron
Video
Taal
English
Uitgever
KhanAcademyKiswahili
Publicatiedatum
2012
Schepper/Auteur
KhanAcademyKiswahili
Trefwoord
Meiosis

Urination

Micturition (peeing) starts with urine flowing from the kidneys to the bladder via ureters. The bladder expands using transitional epithelium. Urine exits through the urethra, controlled by internal and external urethral sphincters. Ureters prevent backflow, thereby reducing infection risk

Onderwerp en thema
Form 1
Biology
Introduction to biology
Concept and terminologies of biology
Type bron
Video
Taal
English
Uitgever
Khan Academy
Publicatiedatum
2014
Schepper/Auteur
Raja Narayan
Trefwoord
Urination