Unit 13 P2 Describe how materials of different states pass into and out of cells. The cells plasma membrane is not only used for structural purposes. Its functions to allow certain substances in and out of the cell. It can allow other substances into the cell against the concentration gradient or allow other substances (for example waste) out of the cell. There are two ways that the cell can transport substances; passive transport processes and active transport processes.
Mitochondria Mitochondria Nucleus Nucleus Lysosome Lysosome Golgi apparatus Golgi apparatus Cell membrane Cell membrane Endoplasmic reticulum (Smooth and rough) Endoplasmic reticulum (Smooth and rough) Cytoplasm Cytoplasm Cell Membrane A cell membrane of the cell. It gives the cell its shape, it is the outer covering of the cell made up from phospho-lipid-protein bi-layer, which allows the materials to enter and to exit. The cell membrane is not one solid piece. It is made of different pieces. Compounds called proteins and phospholipids make up most of the cell membrane.
| | | A) | endoplastic reticulum | | | B) | microtubules | | | C) | cytoplasm | | | D) | mitochondria | | | | | | Feedback: The cell's chemical processes take place in a semifluid material called the cytoplasm. This material provides an ideal environment for organelles because of its fluidity. | | 7 CORRECT | | This shows an example of endoplasmic reticulum. What is the significance of its structure? | | | A) | provides a location for DNA production | | | B) | helps decrease surface area | | | C) | allows selective permeability of cell membrane | | | D) | facilitates breakdown of chemical bonds | | | | | | Feedback: The pleats and folds of the endoplasmic reticulum provides a large surface area where cellular functions, such as breaking chemical bonds, can take place.
MAINTAINING A BALANCE 1.1 Identify the role of enzymes in metabolism, describe their chemical composition and use a simple model to describe their specificity on substrates. - Enzymes are a biological catalyst found in living things that helps control which chemical reactions are to take place. - Most enzymes are made of protein. [pic] 1.2 Identify the pH as a way of describing the acidity of a substance. - pH is a way of describing the acidity or alkalinity of a substance.
* An electrogenic pump is a transport protein that generates voltage across a membrane * Animal- sodium/potassium * Plants- proton pump Understand how a co-transporter works. Where you likely find one? Understand how large molecules and particles are transported across membranes including the role of Vesicles. What is meant by endocytosis? There are several types – what are they and how do they differ?
This is a form of passive transport across a membrane in which a transporter protein facilitates the movement of an impermeable membrane or ion across the plasma membrane down its concentration gradient. In facilitated diffusion, the direction of transport is always down a concentration gradient from one side of the membrane where the substrate concentration is high to the other side of the membrane where the concentration is lower. Facilitated diffusion is powered by the potential energy of a concentration gradient and does not require the expenditure of metabolic energy. The transport proteins responsible for these functions are referred to as uniporters. Amino acids, nucleosides, sugars, and other small molecules are often transported across membranes by uniporters.
| Goigi Apparatus | The main function of the Golgi apparatus is to be responsible for handling the macromolecules that are required for proper cell functioning | It packages and ships molecules made in the ER. | Lysosome | Lysosomes are spherical bag like structures that are bound by a single layer membrane, however, the lysosome shape and size may vary to some extent in different organisms. The lysosome size ranges between 0.1 to 1.2μm. | Lysosomes function as the digestive system of the cell, serving both to degrade material taken up from outside the cell and to digest obsolete components of the cell itself. | P1 tasks 2 Organs | Anatomy | Physiology
Analyze the polarity of the different regions of a phospholipid molecule. Use the model of the phospholipid to describe the structure of the cell membrane. How do water, phospholipids, and proteins interact to produce the cell membrane? * Analyze the polarity and water-solubility of the different regions of the globular protein floating in the phospholipid bilayer membrane shown below. The protein molecule is able to float in the membrane – part of it is embedded in the membrane, part of it sticks into the cytoplasm, and part of it sticks out into the aqueous environment of the cell.
This process occurs in the cytosol of a cell. • What is the role of the citric acid cycle? Include the reactants and the products. Where does it occur? The citric acid cycle takes certain compounds that donate protons and electrons to the electron transport chain.
Fibre Fibre is an essential part of good health, the primary function of Fibre is to keep the digestive system clean, healthy and functioning, although Fibre can not be digested by the body. A useful element of Fibre is the aid it gives on disposing waste and toxins from the body, opposed to substances sitting in the intestines and bowel. This is performed by the disposing of faecal matter. But in the instance if you don’t have enough Fibre and substances sit in your body, build-up will occur and several diseases can be inflicted as a result. Fibre and other digested foods as they pass through the body do not change very much until it reaches the large intestine, the process of excretion after the reaching of the large intestine depends on the type of Fibre is consumed.