Nervous tissue is found in the brain, spinal cord, and nerves. It is responsible for coordinating and controlling many body activities. It stimulates muscle contraction, creates an awareness of the environment, and plays a major role in emotions, memory, and reasoning.
Isotopes are variants of a particular chemical element which differ in neutron number, although all isotopes of a given element have the same number of protons in each atom. The term isotope is formed from the Greek roots isos and topos, meaning "the same place"; thus, the meaning behind the name is that different isotopes of a single element occupy the same position on the periodic table.
Spines primarily have a protective function in plants. The spines can be sharp, and form a physical barrier against herbivores which may want to feed on the plant. Spines however also have other benefits. The spines on a jumping cactus allow segments of the cactus to stick to passing large animals or humans, thereby allowing the cactus to spread to other areas through asexual propagation. Spines are modified leaves, and spines have a much lower surface area than leaves, and therefore can reduce transpirative loss of water by the plant during harsh droughts. Some trees in alpine regions, such as pine trees, have developed spine-like leaves to prevent the accumulation of snow in the branches.
Answer: If one is constructing a phylogeny of reptiles using DNA sequence data of birds, mammals, amphibians or fish, the suitable outgroup to be used are mammals due to the time of divergence from other group of organisms.
Explanation: Phylogeny is used to determine evolutionary relationship between items or organisms. A phylogenetic tree is a graphical illustration of phylogenetic relationship. In phylogeny, an outgroup represent an organism that is more distantly related to other group of organisms.
In a phylogenetic tree, outgroup stands alone. It shows that the time of divergence of that particular organism is far from other group of organisms. Outgroup is used to root a tree and sometimes represent a group that is more ancestral on a tree.
It should be noted that differences in the DNA sequences of the organisms under consideration will determine which organism will serve as the outgroup.
Answer:
The main difference between eukaryotic and prokaryotic cells is that eukaryotic cells have a nucleus.
The nucleus is where cells store their DNA, which is the genetic material.
The nucleus is surrounded by a membrane. ...
Explanation:
All prokaryotes are single-celled (unicellular) organisms.
