Answer:
42,5 mL
Explanation:
We need to use the serial dilution formula beacuse we start with a stock concentrate solution and we need to prepare a new less concentrated one.

<u>DF in the dilution factor, Vi is the initial volume and Vf is the final volume.</u>
The first step is to have the same measurment unit so we need to convert 345 µg to mg.
we know that 1 µg equals 0,001 g, hence:

now the final volume is 0,345 mg protein/ mL and the inital volume is 15mg protein/mL, both of them are in the same unit so we can use the formula


Now since the question said that we already have 1.0mL of the amylase stock solution we need to subtract that 1.0mL to the 43,5 mg protein/mL

So, we need 42,5 mL of diluting buffer if we want a final concentration of 345 µg protein/mL (0.345 mg protein/mL)
A higher temperature gradient causes faster heat transfer, and thus faster convection currents. If the core were cooler, the temperature gradient would be lower, so the convection currents would likely slow down.
Answer:
Flatworms and cnidarians
Explanation:
In simple organisms, such as cnidarians and flatworms, every cell in the body is close to the external environment. Their cells are kept moist so that gases diffuse quickly via direct diffusion. Flatworms are small, literally flat worms, which 'breathe' through diffusion across the outer membrane
To carry out these functions, DNA sequences must be converted into messages that can be used to produce proteins, which are the complex molecules that do most of the work in our bodies. Each DNA sequence that contains instructions to make a protein is known as a gene.The DNA housed in the nucleus is too large to move through the nuclear membrane, so it must be copied by the smaller, single-stranded RNA (transcription), which moves out of the nucleus to ribosomes located in the cytoplasm and rough endoplasmic reticulum to direct the assembly of protein (translation).