All indicate that the universe is expanding.
Answer:
The main difference between acoelomate and coelomate is that acoelomate is an invertebrate that doesn't have a coelom whereas coelomate is an invertebrate that has a true coelom.
A coelom is a fluid-filled body cavity, which is completely lined by the tissues derived from the mesoderm.
Answer:
Cellular membranes or plasma membranes has many functions. Some of these include regulation of cellular transport, and responding to cellular signals or hormones.
<h2>Cellular Transport</h2>
The plasma membrane is made up of the <u>phospholipid bilayer with embedded transmembrane proteins</u>. This makes the cell membrane <u>semi-permeable</u>. Movements of substances depend on the composition of the molecules e.g. glucose and amino acids, as needed by the pancreatic cells. These are larger and uncharged molecules and can't pass freely through the membrane so they utilize the transmembrane proteins via attaching to carrier proteins. This is called <em>passive transport</em>. On the other hand, in <em>active transport</em>, <u>ATP is used</u> to transfer molecules, like Hydrogen, from a low to high electrochemical gradient.
Other kinds of cellular transport are:
- Osmosis and diffusion
- Endocytosis
- Exocytosis
<h2>Cellular Signalling</h2>
The cell membrane is able to signal other neighboring cells by utilizing complex proteins. These proteins may take form as receptors or markers.
<h3>Membrane Receptors</h3>
They act as receivers of extracellular signals and spark intracellular processes. These receive signals from hormones, growth factors, etc.
<h3>
Membrane Markers </h3>
These allow the cells to identify each other and respond if this cell is needs further development as in organ development, or a foreign body to the system.
Answer:
The correct answer is: semi-conservative.
Explanation:
DNA replication is an important process in which the DNA is duplicated before cell division so each daughter cell can have a copy of genetic material.
DNA replication is <u>semi-conservative because one strand of DNA is new and the other one is the old strand</u>. To replicate itself, the DNA double helix is opened, and then each strand serves as a model for the new strands.
DNA replication is <u>not a one-step process</u>, as it takes several complicated steps in which <u>lots on enzymes participate</u> (like DNA polymerase and DNA helicase).
DNA replication is <u>also carried by prokaryotic cells</u>, though it's a much simpler process.
