The correct answer is B. Ordovician period
Explanation:
Plants are mainly multicellular organism that depends mainly on photosynthesis to obtain energy, this includes a wide variety of species such as grass, flowering plants, trees, shrubs, etc. Additionally, plants are considered as one f the two major divisions or kingdoms along with animals. In terms of history, it has been determined first land plants appear during the mid-Ordovician period around 470 million ago, although organisms that were the origin of land plants developed in water in previous periods, also by the Devonian period a wide variety of plants have emerged with features that are still part of plants nowadays. Therefore, plant life first appeared on land during the Ordovician period.
<h2>MCQ:- </h2>
<h3>ANSWER:-</h3>
- Tissue
- Unicellular Prokaryote
- Must be correct
- Not include in any kingdom
<h2>Explanation:- </h2>
(1) Group of cell that work together as one to perform a single function is termed as Tissue . Then the group of tissue combine to form organs and further they combine to organ systems and further they combine to form organ system .
(2) They are unicellular green algae which belongs to family Volvocaceae of the Plantae Kingdom
(3) Hypothesis is the assumption which are taken on the behalf of the observation on small <u>scale</u> . They can be correct or incorrect depends on the number of observation and Hypothesis.
(4) Viruses are included in any of the kingdom because they are on the intermediate line of living and non living as they show properties of non living outside the host and properties of living inside the host
I believe it is gel electrophoresis.
Gel electrophoresis is a techniwue used to separate DNA fragments or other macromolecules such as RNA and proteins based on their size and charge. It can also determine the actual size of a piece of DNA by examining it next to a standard "yardstick" made up of DNA fragments of known sizes.
Answer:
RADON GAS
Explanation:
Radon is a naturally occurring gas, which is produced due to the radioactive decay of the Radium element. It is one of the dense gas that is mostly concentrated in the lower portion of the houses, and are trapped in the cracks and fractures of the walls of houses and buildings.
Radon gas is an invisible, colorless and odorless gas, which is a very harmful gas, and exposure to Radon gas can cause an individual to suffer from cancer.
In recent studies, it has been found that in many parts of North America, a large number of residents are exposed to Radon gas, which led to an increased risk of cancer.
