There was no life on Earth for the first billion years because the atmosphere was not suitable for life. Earth's first atmosphere had lots of water vapor but had almost no oxygen. Later, frequent volcanic eruptions put several different gases into the air.
Answer:
B. analyzes sensory information, stores information, makes decisions
Explanation:
The receptors sense the changes or stimuli. The sensory neurons of the nervous system deliver this sensory information to the processing center, that is, to the central nervous system. The central nervous system serves to store the information and analyze it to determine the best suitable response. The ability of the nervous system to the store and process of sensory information to make the effector organs to exhibit the best response represents its integrative function.
Answer:
about the Trilobites is =Trilobites ( /ˈtraɪləˌbaɪt, ˈtrɪ-, -loʊ-/;[4][5] meaning "three lobes") are a group of extinct marine artiopodan arthropods that form the class Trilobita. Trilobites form one of the earliest-known groups of arthropods. The first appearance of trilobites in the fossil record defines the base of the Atdabanian stage of the Early Cambrian period (521 million years ago), and they flourished throughout the lower Paleozoic before slipping into a long decline, when, during the Devonian, all trilobite orders except the Proetida died out. The last extant trilobites finally disappeared in the mass extinction at the end of the Permian about 252 million years ago. Trilobites were among the most successful of all early animals, existing in oceans for almost 300 million years.[6] . and about the algae is =Algae (/ˈældʒi, ˈælɡi/; singular alga /ˈælɡə/) is an informal term for a large and diverse group of photosynthetic eukaryotic organisms. It is a polyphyletic grouping that includes species from multiple distinct clades. Included organisms range from unicellular microalgae, such as Chlorella and the diatoms, to multicellular forms, such as the giant kelp, a large brown alga which may grow up to 50 metres (160 ft) in length. Most are aquatic and autotrophic and lack many of the distinct cell and tissue types, such as stomata, xylem and phloem, which are found in land plants. The largest and most complex marine algae are called seaweeds, while the most complex freshwater forms are the Charophyta, a division of green algae which includes, for example, Spirogyra and stoneworts.
Explanation:
Answer:
D. It is a process of change during which species in a community are established or replaced
Explanation:
Ecological succession is a process that occurs when a community is being established or replaced.
It shows the change in community over time, focusing on the types of plants and the maturity of plants that are in the community.
Primary and secondary succession are the two types of succession. Primary succession shows the process of change in the establishment of a community. Secondary succession shows the change when a community is being replaced.
So, the correct answer is D. It is a process of change during which species in a community are established or replaced
Answer:
citric acid cycle
Explanation:
check the below attached file for further explanation
