VTCT Sport & Active LeisureL3 Certificate in Sports Massage Therapy (QCF)
Assignment 1 – Functional Anatomy & Physiology Unit UV30378
Lou Davidson – March 2012
1a – Explain the structures of a human cellMost human cells contain small structures known as organelles (“little organs”), each of which performs a highly specialised task, such as manufacturing protein. Organelles are usually surrounded by a membrane, and they float in a jelly-like substance called cytoplasm. Ninety percent of cytoplasm is water; it also contains enzymes, amino acids, and other molecules needed for cell functions. The structure of a human cell can be broken down more microscopically as follows: * Nucleus – The cells control centre mainly contains chromatin, a granular material composed of DNA, the cells genetic material, and proteins. The inner nucleolus is made up of RNA and proteins. The nucleus is surrounded by the nuclear envelope, a two-layered membrane with pores. * Centrioles - These two structures made of hollow tubules play a key role in cell division. * Mitochondrion – This structure produces a substance called adenosine triphosphate (ATP), which is the carrier of energy in all cells. * Endoplasmic Reticulum – This organelle helps to transport materials through the cell. Rough reticulum is the site of attachment for ribosomes; smooth reticulum is the site of fat production. * Ribosomes – These small, granular structures play a key role in the assembly of proteins. * Golgi Complex – A stack of flattened sacs receives and processes protein that has been dispatched by the endoplasmic reticulum. The proteins are modified and released at the cell membrane. * Microvilli – Some cells, such as those lining the small intestine, have projections that increase their surface area to facilitate absorption. * Lysosome – The powerful enzymes of this organelle degrade dangerous materials taken into the cell, such as bacteria, and also dispose of other unwanted substances and any worn-out organelles. * Cell Membrane – The membrane encloses the contents of the cell and regulates the flow of substances into and out of the cell. * Vacuole – This sac transports and sores ingested materials, waste products, and water. * Visicles – These sacs contain various substances, such as enzymes, produced by the cell; they secrete them at the cell membrane. * Nucleolus – A small structure inside the nucleus that plays an important role in ribosome production. * Peroxisome – Enzymes that are made in these sacs oxidize some cell substances * Cytoskelton – The internal framework of the cell is made of two main types of structure. Prominent in all cells are filaments, which are thought to provide support for the cell. Hollow microtubules are thought to aid movement of substances through the cells watery cytoplasm. 1b – Describe the processes of osmosis and diffusionOsmosis may occur when there is a partially permeable membrane, such as a cell membrane. When a cell is submerged in water, the water molecules pass through the cell membrane from an area of low solute concentration (outside the cell) to one of high solute concentration (inside the cell); this is called osmosis. The cell membrane is selectively permeable, so only necessary materials are let into the cell and wastes are left out.Diffusion is a main form of transport for necessary materials such as amino acids within cells. Metabolism and respiration rely in part upon diffusion in addition to bulk or active processes. For example, in the alveoli of the lungs, due to differences in partial pressures across the alveolar-capillary membrane, oxygen diffuses into the blood and carbon dioxide diffuses out. Lungs contain a large surface area to facilitate this gas exchange process.1c – Explain Basal Metabolic Rate Basal metabolic rate...
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