In the 5—7 million years that the hominid lineage has been diverging from its common ancestor with the great apes, dozens of hominid species have arisen, often with several species coexisting in time and space. As recently as 30,000 years ago, Homo sapiens coexisted with Homo neanderthalensis. Both species had large brains and advanced intellects. The fact that these traits were common to both species is most easily explained by which of the following?

#Question id: 11306

#Unit 2. Cellular Organization

#Question id: 12696

#Unit 8. Inheritance Biology

#Question id: 585

#Unit 1. Molecules and their Interaction Relevant to Biology

In an enzyme reaction involving one enzyme and one substrate, the rate of the reaction depends on

#Question id: 5218

#Unit 11. Evolution and Behavior

Several of the different globin genes are expressed in humans, but at different times in development. What mechanism could allow for this?

#Question id: 1382

#Unit 4. Cell Communication and Cell Signaling

Following statements are regarding to cell-cell and cell–extracellular matrix junctions and their adhesion molecules.

A. Adherens junctions and desmosomes are integrin-containing anchoring junctions that bind the membranes of adjacent cells, giving strength and rigidity to the entire tissue.

B. Hemidesmosomes are cadherin-containing anchoring junctions that attach cells to elements of the underlying extracellular matrix.

C. Integrins are a large family of αβ heterodimeric cell-surface proteins that mediate both cell-cell and cell-matrix adhesions and inside-out and outside-in signaling in numerous tissues.

D. Tight junctions block the diffusion of proteins and some lipids in the plane of the plasma membrane, contributing to the polarity of epithelial cells. They also limit and regulate the extracellular (paracellular) flow of water and solutes from one side of the epithelium to the other.

Which of the following statements are incorrect?