Answer:
A theory.
Explanation:
A scientific theory is the product of related observations supported by evidence acquired through scientific investigation. An example of a theory includes the theory of evolution (which explains observations in the fossil record, phylogenetic patterns observed in species, and these results have been aquired through scientific investgation and analysis of things like the genome of species, and archeaological evidence)
Answer:
The Y chromosome is an accurate indicator of a person's external sex organs.
Explanation:
Since females have two X chromosomes while males have one X and one Y chromosome, if you are aware of the presence of a Y chromosome you can safely assume that a person is a male. Therefore, you can assume what external sex organs a male has.
For photosynthesis to occur, there must be sunshine and water present in the system. ATP is how the light is actually converted to energy that the plant uses to grow.
Xylem and phloem
hope u got it right
Answer:
Explanation:
The main function of the plasma membrane is to protect the cell from its surroundings. Made of a phospholipid bilayer with embedded proteins, the plasma membrane is selectively permeable to ions and organic molecules it also regulates the movement of substances in and out of cells. Plasma membranes must be very flexible in order to allow certain cells, such as red blood cells and white blood cells, to change shape as they pass through narrow capillaries. Membrane receptors provide extracellular attachment sites for effectors like hormones and growth factors, which then trigger intracellular responses. Some viruses, such as Human Immunodeficiency Virus (HIV), can intercept these receptors to get into the cells, causing infections.