Science Essay for Lesson 20

Bio Lesson 20 Essay

4/26/17

(I had a different essay but it deleted itself so this is my 2nd essay)

Answer ONE of the questions below in an essay of about 150-250 words (you may write a longer essay if you wish). Be sure to include facts and details from the past 4 (or more) lessons, as this will help you remember and understand them better.

(notes for this essay used from Lesson 16,17,18, and 19 )

You scrape your knee so deeply that it bleeds. Later a scab forms over the wound. When the scab falls off, you have new skin underneath. Where did the new skin come from? Describe the process in detail.

Words: 569

When you scrape yourself and it’s a deep cut so it bleeds this is about the science behind how your body heals cuts and scrapes. Human bodies are amazing in the way they can heal and cure themselves! A cell is the most basic unit of life. Cell signaling does a few different things but one use of it is responding to hormones. Cell signaling is exactly what it sounds like communication with other cells needed for reproduction, and death among other uses. Proteins play a big role in cell signaling. Reception involves receptors that receive the chemical signal or ligand. G Protein-Coupled Receptors are on surface human cells, there are about 1,000 different kinds. Most surface receptors are GPC’s. They do vision, smell, and taste and are involved in most of our senses. RTKs (Receptor Tyrosine Kinases) can trigger several transduction pathways and ion channels. When open ion channels receptors bond with a ligand. Ion channel receptors play a role in the function of the nerve cells. Cells go through a life cycle like anything else. Going on to reproduction,(apart of the cell cycle) cells needs to reproduce if the conditions are fit. Cells reproduce through unicellular (one cell organism) reproduction it splits itself and makes a copy. For tissue repair and replacement, when you're injured you heal with more cells that replace and repair tissue. A scab that forms over a cut covers the opening and replaces lost or damaged cells. Receptors on the surface are designed to pick up a certain signal. They know there are more skin cells around the wound and that means the wound is healed! This is cell-cell recognition called apoptosis “taking note” of infected or damaged cells, cell murder. There is a receptor on the surface of the cell for the “death” signal. By then the healing process stops because it is complete! This obviously cannot be done for a large gash on your leg or something like that a serious cut would need stitches and medical help. The cell cycle alternates between interphase and the important mitotic phase. The cell cycle starts in the interphase then moves onto the next phase. The mitotic phase creates genetically identical cells called “daughter cells” with identical chromosomes. Mitosis means a thread, which is now known as DNA. In cell division, the cells copy a specific number of chromosomes in your body. A chromosome is a single DNA-protein that contain lots of genes. A chromatin is a complex of chromosomes and genes in a cell, (as well as proteins). In MTOC it controls the growth of microtubules. This is the process of mitosis the duplication of your somatic cells (body cells). In cell signaling a “checkpoint” receives the “stop” or “go” for a cell signaling for the S phase and G2 phase. This whole cycle is driven by Kinases. There are four stages of mitosis called PMAT. During the Prophase in the cell, the cells start to get ready for mitosis. During the telophase (I’m skipping around phases to get to the point) two new nuclei form the cleanup begins and then the cell begins to divide. Two new nuclei form the cleanup begins and then the cell begins to divide. That is where the new skin on a cut comes from, and how your body heals minor cuts and injuries in a detailed science look at the process of our bodies healing.

*I had trouble condensing 4 Lessons together with information included from each Lesson so this is a bit longer but it hits all four lessons the word count is added as well*