Answer:
The Mitral/Bicuspid Valve
Explanation:
The heart is composed of 4 chambers: left and right atria, and left and right ventricles. The “right heart” (right atrium and ventricle) receives deoxygenated blood from the systemic circulation through the Vena Cava, and impels this blood towards the lungs through the Pulmonary Arteries where it will be oxygenated. The “left heart” (left atrium and left ventricle) receives oxygenated blood from the pulmonary circulation through the Pulmonary veins and impels this blood towards the systemic circulation through the Aorta artery.
The systemic and pulmonary circuits work in series, and maintaining the unidirectional course of the blood flow is very important. This can be done by the presence of fibrous valves that are present between the atrium and the ventricles, and in between the ventricles and the Pulmonary/Aorta artery.
The location of these structures are as follows:
Systemic circulation ⇒ Right Atrium → [Tricuspid Valve] → Right Ventricle → [Pulmonary Valve] → Pulmonary Artery ⇒ Pulmonary circulation
Pulmonary circulation ⇒ Left Atrium → [Mitral/Bicuspid Valve] → Left Ventricle → [Aortic Valve] → Aorta ⇒ Systemic circulation
Well it happens every six months, one in summer in June and winter December. And if i'm wrong then i understand :) <span />
Answer:
In the Cretaceous period, Mesozoic Era forests begin to look like modern day forests and included a variety of conifers and decidous trees.
Explanation:
The Cretaceous period was the last and longest segment of the Mesozoic Era.It lasted approximated 79 million years from the minor extinction events that closed the Jurassic Period about 145.5 million years ago to the Cretaceous - Palogene ( K-Pg) extinction event dated at 65.5 million years ago. This era have seen more dinosaurs than before.The horned Cretaceous dinosaurs appeared, like the Triceratops and Centrosaurus. The armored Ankylosaurus, duckbilled Parasaurolophus, and large carnivore Tyrannosaurus were a few of the quickly evolving dinosaurs.
Mass movements (also called mass-wasting) is the down-slope movement of Regolith (loose uncemented mixture of soil and rock particles that covers the Earth's surface) by the force of gravity without the aid of a transporting medium such as water, ice, or wind.
The rate at which it moved
The type of motion is the most important characteristic of a slope failure, and there are three different types of motion:
If the material drops through the air, vertically or nearly vertically, it’s known as a fall.
If the material moves as a mass along a sloping surface (without internal motion within the mass), it’s a slide.
If the material has internal motion, like a fluid, it’s a flow.
