By injecting Mesenchymal Stem Cells with ability to express high amount of Akt or protein kinase B in myocardium, researchers witnessed restored cardiac function and inhibition of ventricular remodeling. The effect was seen after two weeks of administration of cells. The culture containing hypoxic Akt-MSCs (conditioned medium) inhibits apoptosis or cell death induced due to hypoxia. Also, it triggers in vitro contraction of cardiomyocytes, the cardiac cells specifically responsible for contraction function.
The desired functional improvement can occur in short time which is less than 72 hours, the reason for which was hypothesized as paracrine action of cells. Hypothesis was proved by upregulation of genes that code for factors responsible for above mentioned effects (apoptosis and contraction). The factors are FGF-2, VEGF, HGF etc.
Learn more about stem cells -
brainly.com/question/24702243
#SPJ4
Answer:
Fossils provide direct evidence of evolution. They show the changes of animals from ancient organisms to present form. Fossils are the preserved remains of earth layers. There are 4 types of fossils-
Original fossils that are not very old. e.g. teeth, skeleton, shells.
Frozen fossils
less permanent fossils
casts, molds, and prints - wings, skin, leaves, etc.
The fossils show the adaptive radiation in horses, humans. The transition fossils form the connecting link between different groups such as fish and amphibians, reptiles and birds, etc.
e.g. Archeopteryx is the connecting link between the reptiles and birds.
The modern horse Equus have several ancestor species, we came to know from the fossil records.
The fossil record shows the evolution of humans and their ancestors.
Answer:
Matter cycles through an ecosystem through processes called biogeochemical cycles.
Explanation:
Photosynthesis
Plants build carbohydrates by taking in carbon dioxide from the atmosphere.
Carbon moves through the food chain
As organisms eat other organisms, carbon moves up the food chain. Molecules in the food that contain carbon transform into the organic molecules that make up the living body.
Carbon moves back to the environment
Organisms use food molecules, containing carbon, as a form of energy. The process of cellular respiration breaks down food molecules into carbon dioxide.
Contribution of industry
Humans contribute to moving carbon dioxide back into the atmosphere through the combustion of fossil fuels.
Use of fossil fuels
Today's fossil fuels were formed hundreds of millions of years ago by plants deposited in the Earth. The decomposition of the plants slowed down in such a way that their organic molecules are used for natural gas, coal and oil.
Diffusion into the air
From the oceans, carbon dioxide diffuses into the air. This creates a large amount of carbon, which is then taken in by plants to start the cycle over again.
The parent cell divides into two "daughter" cells. This will repeat over and over, and this is what we define as the cell cycle!
Fun Fact: Each stage of the cell cycle, such as G1 (Growth/Gap 1), Synthesis/ Stage, then G2/ Gap 2 stage, then following mitosis, has their own checkpoint! These checkpoints review/ revise what the cell has done during the stage.
