11 - 20 van 21 bronnen weergeven

Enzymes

Enzymes as catalysts for reactions in biological systems; discussion of substrates, active sites, induced fit, and activation energy.

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
Enzymes

Human evolution overview

From the extinction of the dinosaurs to humanity.

Onderwerp en thema
Form 1
Biology
Introduction to biology
Concept and terminologies of biology
Type bron
Video
Taal
English
Uitgever
Khan Academy
Publicatiedatum
2011
Schepper/Auteur
Sal Khan
Trefwoord
Evolution
Human Evolution

Matter and energy in food webs

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.

Onderwerp en thema
Form 2
Biology
Balance of nature
Food chain and food web
Type bron
Video
Taal
English
Uitgever
Khan Academy
Publicatiedatum
2022
Schepper/Auteur
Sal Khan
Trefwoord
Food webs

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

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

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

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

Worked example: analysing a generic food web

We can analyse the arrows in a food web to identify producers, primary consumers, secondary consumers, and decomposers.

Onderwerp en thema
Form 2
Biology
Balance of nature
Food chain and food web
Type bron
Video
Taal
English
Uitgever
Khan Academy
Publicatiedatum
2022
Schepper/Auteur
Sal Khan
Trefwoord
Food webs