Teoría
wHAT ARE THE INSIDES OF CELLS LIKE?
Shapes:
-Cells have very varied shapes:
-Two kinds of cells:
-Cells have very varied shapes:
- Cylindrical
- Spherical
- Star-shaped
- Disc-shaped
-Two kinds of cells:
- Procaryotic: Where the nucleus is not separated from the rest of the cell
- Eucaryotic: Where the nucleus is separated from the rest of the cell
Parts of the cells
-Endoplasmatic reticulum: There are two kinds: the rough ER stores and transports the proteins, the smooth ER makes lipids
-Vacuoles: Saccules which store substances
-Lysosomes: Which are transports to vacuoles, the content of which must be destroyed.
-Golgi apparatus: This consists of 5-10 flat saccules which produce glucose and store bio-molecules
-Vesicles: Very small saccules which store and transport substances
-Mitochondria: These are responsible for the respiration of the cell, a set of reacction by measons
-Chioroplasts: Similar organulles the amyloplats but are exclusive to vegetable cells
-Centrosome: This is related to the movements of the cell and organulles
- Ciliar and fraguella: These are responsible for the displacement of the cew
- Cellular membrane: The cellular membrane consists of lipids and protens. It surrounds the cell and in certain areas it goes into the interior of the cell.
- Cytoplasm: The cytoplasm is the space which exists between the cellular membrane and the nuclear envelope. It consists of a liquid substance know as hyaloplasm which contains the microtubules and microfilaments.
- Organulles:
-Endoplasmatic reticulum: There are two kinds: the rough ER stores and transports the proteins, the smooth ER makes lipids
-Vacuoles: Saccules which store substances
-Lysosomes: Which are transports to vacuoles, the content of which must be destroyed.
-Golgi apparatus: This consists of 5-10 flat saccules which produce glucose and store bio-molecules
-Vesicles: Very small saccules which store and transport substances
-Mitochondria: These are responsible for the respiration of the cell, a set of reacction by measons
-Chioroplasts: Similar organulles the amyloplats but are exclusive to vegetable cells
-Centrosome: This is related to the movements of the cell and organulles
- Ciliar and fraguella: These are responsible for the displacement of the cew
- Nucleus: Is generally spherical in shape and is confined by a nuclear envelope. This is a double membrane which as nuclear pores to allow the cyroplasm to pass through
Tissues
-Pluricelluar organisms are made up of many cells which, as they are joined together, increase the size of the living being and work together to make posible their joint life.
- Thallus structure: the is found living beins whose cells are practically the same
- Tissue organisation: this is found in living beings whixh are made up of various different types of cells
What is the nutrition?
-We know that the following concepts are two of the main characteristics of living beins
-Living metter changes continuosly. During growth, for exemple, new cells must be built and they must increase in size. In an adult organism, which has finished growing, cells must alter a wound, the affected tissue is rebuilt a scar is formed
-Energy is necessary for any process involving living beings. When a seed germinates or when an animal moves a muscle energy is consumed.
-No living being, therefore, can be isolated from its enviroment. They all need to obtain certain substances from their environment and use them for building their own matter or for obtain energy
-The function of nutrition allows living beins to obtain the matter and energy they need for making their own matter for cerrying out their vital functions
-Living metter changes continuosly. During growth, for exemple, new cells must be built and they must increase in size. In an adult organism, which has finished growing, cells must alter a wound, the affected tissue is rebuilt a scar is formed
-Energy is necessary for any process involving living beings. When a seed germinates or when an animal moves a muscle energy is consumed.
-No living being, therefore, can be isolated from its enviroment. They all need to obtain certain substances from their environment and use them for building their own matter or for obtain energy
-The function of nutrition allows living beins to obtain the matter and energy they need for making their own matter for cerrying out their vital functions
Health
-Whe can define health as the absence of illness, we can also say that health is the state of wall-being of the body
-But health is not only a physical concept. It is also a psychic concept,.
Healthy habits
-Healthy habits are those which help us to stay healthy and prevent illnesses
-Whithout doubt, one of the most important habits is a healthy diet
-Remember, funrthermore, that it is important to follow a number o healthy behavioural patterns
-But health is not only a physical concept. It is also a psychic concept,.
Healthy habits
-Healthy habits are those which help us to stay healthy and prevent illnesses
-Whithout doubt, one of the most important habits is a healthy diet
-Remember, funrthermore, that it is important to follow a number o healthy behavioural patterns
Illnesses
-All illness is an anormal proces which alters, modifier or prevents the activity of a part of our body or the complete orfanism
-Illnesses are clasified into different groups:
-Illnesses are clasified into different groups:
- Infectious: diseases are those which are due to the action of microorganism
- Congenital: illnesses are those which exist at birth
- Hereditary: illnesses are transmitted from parents to their offspring
- Deficit: disorders are due to the deficit or abscene of vitamins, minerals or any other important substance
- Chronic: illnesses are those which are prolonged in time and have no possible cure
- Epidemic: is a disease which affects a community like a city
- Pandemic: is a disease which affects a very large territory like one or more continents
Transplants
-Nowadays, organ and tissue transplants are an essential way of saving lives of a lot of ill people
-A transplant is the transfer of an organ, tissue or group of cells from one indiciduall to another to replace an organ or tissue hat no longer works as the result of an accient or a dissease
-Stem cells are capable of developing into one or more types of cells
-A transplant is the transfer of an organ, tissue or group of cells from one indiciduall to another to replace an organ or tissue hat no longer works as the result of an accient or a dissease
-Stem cells are capable of developing into one or more types of cells
Digestive system
Digestive process:
- As all with animals, human beings dotain proteins, facts and glucids from foood. It is a very difficult task to do this amd it is done by the digestive apparatus.
- The movement of food thorugh the digestive tube is done thanks to what are know as peristaltic movements. These consists of the narrowing of the tube through the contraction of the muscles of the walls
- Acording the changes in the food, digestion con be machinical or chemical
- Mechanical digestion: consist of cutting, crushing, removing and diluting foods
- Chemical digestion: on the other hand, is done through the action of various substances which attack the foods and bring about chemical changes in them
- The chyle passes from the duodenum to the following parts of the small intestine, the jejunum and the ileum
- The absorption consists of the useful substances in the food crossing through the intestinal wass and into the blood vessels
- The remains of the chycle which cannot be used pass into the largex intestine
Respiratory system
Interchanging gases
- The smallest respiratory tracts, the bronchioles, are conected to the alveoli
- The interchange of gases between the air and the blood occurs in the alveoli. The blood occurs in the alveoli. The blood that reaches the alveoli through the veins is full of carvon dioxide
- So the blood is oxygenated when it leaves the alveoli and returns to the heart through the veins
- Our cells not always require the some amount of oxygen . During intestine physical exercise, the cells of our muscles work more and require more oxygen
- Respiratory rhythm, in other words, the number of inspirations per minute, varies depending upon oxygen requirements.
- Normally 12 inspirations per minute. After heavy exdercise, this number may increase brusquely to some 40 inspirations per minute
RESPIRATORY SYSTEM
666Blood circulation:
- Blood circulation in human beings is double and complee. It is double because it has two circuits and complete because the blood in the beins never mines with te nlood in the arteries
- The circularion is completed by a series of vessels and glans¡ds which from the lymphatic system, which, among other functions, is responsible for transport of.
- The blood transports the substances through the human body and other vertebrates. It is made up of varius blood cells which floor in a liquid called the blood plasma
- Leukocytes: or white blood corpucles are cells
- Red blood corpuscles
- Platelets: are not complete cells but small bits of cytoplasm from other cells
- Each one of these cells carroes aout a function
- Erythorocytes transports transports oxygen an CO2
- The leukocytes defend the body from infection
- The platelets are involved in the coagularion of the blood
- The plasma, besides being the support for the blood cells is the means of transport for many of the substances carrie by trhe blood
- Every beat of the heart is a set of movements called the cardiac cycle which is carried out in some 0´8 s
- During the cycle, the chambers of the hearth may be relaxed or contracted
- The cardiac cycle beins with the relaxation or diastole of the auricles through the pulmonary veins and cavas
- When sufficient blood has entered the auricles, these contract. The atrioventricular vales open and the blood moves into the ventricles
- When the ventricles contract, the blood pushes the semilunar valves, which separate the ventricles from the pulmonary arteries and the aorta
- When the blood has left the ventricles, the relax. The seminular valves close, producing the second sound
- The beating of the heart is what makes the flow of bloof in the arteries discontinuous. The blood advances along the inside of the arteries with more force during the systole and whith less force during the diastole
Excretory system
Excrection:
- A series of waste substances are produced as a result of the nutrition of the cells or our body. If these were to acumulate they would be toxic for the cells
- The cells release the waste substances into the blood
- Excrection is the name of the process of elimimation the waste substances from the bloof. It is realy a cleaning process in which the blood is filtered to get rid of all the waste substances
- Urine is the liquid of excretion and it contains the toxic substances which must be expelled from the body
- Urine is formed in the nephrons in two passes
- The blood is filtered in the glomerulus. The bloof plasma passes into the inside of nephron
- The filtered liquid passes through the rest of the nephron. Some substances of the liquid return to the blood: proteins, glucose and water
- The urine is collected in the renal pelvis and taken wia the ureter to the bladder where it is stored until it is expelled