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Genetic distance between human groups

By: HWC, Views: 4573

One proposed family tree for modern humans. This family tree is based on nucleic-add hybridization studies of many genes and immuno-logical comparisons. Branch points show presumed genetic divergences. This data indicates that the greatest genetic distance separates humans native to Afri...

Primate Evolutionary Tree Animation

By: HWC, Views: 3873

Presumed evolutionary branchings in the primate family tree. The first primates arose between 85 and 65 million years ago. The common ancestor of apes and hominids branched off from Old World monkeys about 23 million years ago. The hominid lineage, which includes humans and earlier humanlik...

Evolutionary tree of life Animation

By: HWC, Views: 1382

An evolutionary tree of life that reflects mainstream thinking about the connections among major lineages (bya = billions of years ago, mya = millions of years ago). By about 3.8 billion years ago, chemical and molecular evolution had produced the first living cells. The first major divergenc...

Generalized life cycles for plants and animals Animation

By: HWC, Views: 1781

But the life cycles of plants and animals differ in their details. In animals, a multicelled diploid stage gives rise to single-celled haploid gametes, the eggs and sperm. These gametes combine at fertilization to form a diploid zygote, which grows and develops into a new multicelled animal...

Cognitive development by Piaget (Preoperational stage or intelligence)

By: HWC, Views: 6932

The next stage of cognitive development proposed by Piaget, is the preoperational stage, roughly between the ages of 2 and 7. At this stage Piaget asserted that a child has what he called preoperational intelligence. hey can mentally representing objects, but do not have a system for organising...

Darwin's Observation (Fossils, Galapagos Islands & Africa ) and Natural Selection (Adaptive Traits)

By: HWC, Views: 7609

Along Darwin's voyage, he made many observations. Each one added to his understanding of how organisms change over time. Darwin was already familiar with fossils and knew that many fossils were very different from living organisms. But, also there were some fossils that were very similar to li...

Interpreting a cladogram Animation

By: HWC, Views: 1376

Using a cladogram to determine relative relatedness and whether the lungfish is more closely related to a human or to a trout. To determine the relative relatedness, we begin by tracing the branches from the human and the lungfish to the point where they meet. We'll call this node 1. Now...

Photosynthesis and Van Helmont Experiment

By: HWC, Views: 6978

All energy on Earth comes from a star, the Sun. Light must travel 160 million kilometers to reach Earth where plants capture this light energy and convert it to chemical energy in the form of sugars. This biochemical process is called PHOTOSYNTHESIS. The summary equation for photosynthesis is ...

Labor and Delivery - Postpartum Assessment

By: Administrator, Views: 474

The postpartum patient's emotional status plays a significant part in her recovery and her adjustment to her infant. Postpartum hospital stays are very brief, so nurses must make every encounter with the patient meaningful. Developing a systematic method of assessing the patient will save time an...