Calcite occurs in igneous, metamorphic, and sedimentary rocks and is the most commonly encountered carbonate mineral.
Cells, like humans, cannot generate energy without locating a source in their environment. However, whereas humans search for substances like fossil fuels to power their homes and businesses, cells seek their energy in the form of food molecules or sunlight. In fact, the Sun is the ultimate source of energy for almost all cells, because photosynthetic prokaryotes, algae, and plant cells harness solar energy and use it to make the complex organic food molecules that other cells rely on for the energy required to sustain growth, metabolism, and reproduction.
Cellular nutrients come in many forms, including sugars and fats. In order to provide a cell with energy, these molecules have to pass across the cell membrane, which functions as a barrier — but not an impassable one. Like the exterior walls of a house, the plasma membrane is semi-permeable. In much the same way that doors and windows allow necessities to enter the house, various proteins that span the cell membrane permit specific molecules into the cell, although they may require some energy input to accomplish this task
The forearm of birds, reptiles, and humans illustrates a homologous body structure.
- Similar physical characteristics found in species with a shared origin are known as homologous structures, although these characteristics have entirely different biological purposes.
- The limbs of humans, cats, whales, and bats are examples of homologous structures.
- All of these structures—arm, leg, flipper, and wing—are supported by the same type of bone structure.
- The arms of a person and the wings of a bat are excellent examples of homologous structures. Because both bats and people are mammals, they have a common ancestor.
- Even though they appear considerably different from one another from the outside, a bat's wing and a human arm have remarkably comparable internal bone structures.
- Wings help bats fly, whereas arms enable human interaction with their environment. The wing and the arm also have various purposes.
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The alveoli needs of the epithelium for the gaseous exchange and stratified squamous epithelium are formed of multiple layers the difficulty in a gaseous exchange
Answer:
According to the base-pairing rule A form base pair with T with two hydrogen bond and G pairs with C with 3 hydrogen bond in DNA. But in RNA T is replaced by U that means A pairs with U in mRNA.
So according to this the nucleotide sequence of the mRNA molecule transcribed from the GTA codon of DNA will be CAU. tRNA are the molecules that pairs to the triplet codon present on mRNA through its anticodon loop which have nucleotide sequence just opposite to triplet codon it binds with.
Each tRNA has attached amino acid according to the anticodon sequence it has. So the anticodon sequence on tRNA will be GUA against the CAU codon sequence of nucleotide on mRNA and this tRNA must be attached with histidine amino acid.
