Answer: to stretch their legs.
Explanation:
Answer:Negative feedback is a type of regulation in biological systems in which the end product of a process in turn reduces the stimulus of that same process.Sometimes referred to as a “negative feedback loop”, negative feedback occurs when the product of a pathway turns the biochemical pathway off.
Explanation:
Answer:
1- Option A) describes an index fossil. Trilobite existed for a short time, but was abundant and lived in many locations.
2- Option B) Continents were once joined and have since drifted apart.
Explanation:
1) Fossils are animal and vegetable rests found in different strata of sedimentary rocks. Sedimentary layers deposit chronologically, so they are used to reflect history. They keep in each layer some of the forms of life that inhabited that area in the past. These fossils turn to be very useful while dating ages. The term Index fossils refer to those fossils that only existed in a given era or geological period during evolution.
Index fossils must:
• Be easily recognizable and distinguishable from all the other fossils
• Have lived in a relatively short geological period
• Present a wide geographic distribution
• Have lived in different sedimentary basins
• Appear in different types of rocks
• Be abundant
<em>A) Trilobite existed for a short time, but was abundant and lived in many locations. </em>The species accomplish the requirements. It is easily recognizable, had a wide geographic distribution, was abundant, and lived for a short time.
2) The tectonic plates theory states that there is a continual movement of the crust. It explains the movement of the different plates and their directions and interactions. The continental drift theory explains how these movements have been taking place since millions of years ago. When continents were together in a unique continent, many species used to inhabit it. When plates started to separate, they took some of these species that got apart by the ocean. Some species were already dead and fossilized, while some other organisms died during continental drift and got fossilized after the divergence. <em>The existence of the same fossils, placed in the same layers and of the same age, suggests that they used to inhabit the same area and died during the same time, meaning that continents were together when they got fossilized. </em>
Answer:
inherited traits that increase an organisms chance of survival , also determine an organisms niche
Explanation:
An adaptation is a variation , or genetic modification , that supports an organism , such as a plants or animals , endure in its environment
Answer:
Option 3, Chromatids remain attached to one another until anaphase
Explanation:
Centromere lies at the center, end or other points of the chromosome and joins the two sister chromatids. During cell division, the spindle fibers attaches at the centromere and detaches the chromosomes during the anaphase of the cell division to ensure that each daughter cell gets equal number of chromosomes at the end of mitosis. Centromere plays an essential role in the separation of chromosomes.
Hence, option 3 is correct
