The right answer is vein (it contains blood and has valves).
The infra-cardiac veins of small and medium caliber possess this system of fight against gravity. The valves consist of a dense connective tissue, surmounted by endothelial cells, corresponding to a fold of the intima. They allow blood circulation in the sense organ / heart but prevent venous reflux.
The three liquids will form three layers, the bottom layer is more dense and the top layer is less dense
1. Biological control is the intentional manipulation of natural enemies by humans for the purpose of controlling pests.
2. Mechanical control includes mowing, hoeing, cultivation, and hand pulling.
3. Chemical control is the use of herbicides.
Explanation:
Generate electricity Fossil fuels can be burned to power vehicles like cars, but they can also be used to:generate electricity
1. Nucleus step1: DNA is transcribed into mRNA
2. Ribosome step2: mRNA is translated into protein
3. Endoplasmic Reticulum step 3: Newly synthesised proteins are transported.
4. Golgi apparatus Step 4: Proteins are modified then transported away
In Golgi body or apparatus, the proteins are modified, sorted and packaging occurs for secretion.
