Answer: The correct option is B. Vertebrates appeared in the oceans before they moved on to land.
Vertebrate paleontology involves study of fossils of the vertebrates starting from the earliest fishes to the ancestors of modern day mammals. The spreading up of life from water to land needed modifications and adaptations such as protection from drying and support against the gravity. The tetrapod vertebrates evolved and started to live on land from oceans during the Devonian period. The succession of the Devonian period showed fossil evidences towards terrestrialization
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Answer: c) central vein.
Explanation:
The liver is an organ that is present both in humans and in vertebrate animals. It secretes the bile, essential for the digestion of fats, and it also has many other functions, including the synthesis of plasma proteins, storage of vitamins and glycogen and detoxifying function. It is responsible for removing various substances from the blood that may be harmful to the body, including alcohol, making them harmless.
The liver is divided by the sickle cell ligament into two main lobes, right and left. <u>There are two other smaller lobes, the square lobe and the caudate lobe</u>.
The hepatic triads are triangular areas located at the angles of the hepatic lobules, made up of a lax conjunctive stroma. <u>They contain a branch of the hepatic artery</u> (that irrigates the liver<u>),</u> <u>a hepatic portail vein</u> (a thick blood vessel that carries blood from the gastrointestinal tract and spleen to the liver so that nutrients are metabolized<u>)</u> and <u>a bile duct</u> (transports bile into the small intestine). Therefore, it does not contain a central vein.
Answer:
Option (2), (3) and (4).
Explanation:
Charophytes are the group of some green algae of fresh water. The cahrophyta can be included in both the division and super division. Embryophyta has been emerged from the charophyta.
A student confirm whether the algae is charophyte or not by looking at the specific features. The cahrophytes has well defined sexual characters and the structure of sperm cell, the presence of phragmoplast confirms the charophytes. The cellulose synthesizing ring complex is also present in charophytes.
Thus, the correct answer is option (2), (3) and (4).
Answer:
b
Explanation:
In this question, the context for exponential growth is assumed to occur naturally. Because lab experiments are not natural and must happen in well controlled studies, it cannot limit exponential growth.