Principles Of Cellular Anabolic And Catabolic Processes Biology Essay

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Explain the principles of cellular anabolic and catabolic processes, using the glycogen metabolic pathway in the liver as an example. Principles of metabolic processes: catabolic and anabolic change, enzymic reactions, role of co-factors, inhibitory and stimulatory influences; concept of metabolic pathways

According to …., cellular anabolic process is a phase of metabolism that builds bigger molecules from the smaller ones. This process also synthesizes normal substance into complex ones for living tissues. It is basically a part of metabolic process. Usually this process is determined by the degradative or biosynthetic activity. Cellular anabolic processes consume energy to reduce net cellular entropy. Mainly, it is a process of diminution. Anabolic process may be shown as:

Simple molecules + Energy Complex molecules

According to………, catabolic process is a phase of metabolism where energy is produced by the breakdown of complex nutrients like proteins, starches, and fats, into simpler ones. In liver, catabolic processes give up a net synthesis of ATP at the equal rate of rise in the internal entropy. NADH + H+, FADH2, FMNH2 are produced from almost all the cellular catabolic process from the oxidation of substances which are usually carbohydrates, fatty acids and amino acids. Catabolic process in liver has been shown below:

Complex molecules Simple molecules + Energy

Analyse the transport of compounds across cell membranes, giving an example each of passive and active transport.


According to …., The cell membrane is the external living border of cell which gives it mechanical power and form and controls the passage of molecules of the cell. There are two types of transport of compounds across the cell membrane and they are:

a) Passive transport and

b) Active transport


Passive transport: This process is determined by membrane transporters by facilitate crossing or the kinetic energy of the molecules.


Active transport: It depends on the spending of cellular energy ( Form: ATP hydrolysis).

Explain ATP synthesis, storage and utilisation by muscle cells.

ATP synthase (EC is a general term for an enzyme that can synthesize adenosine triphosphate (ATP) from adenosine diphosphate (ADP) and inorganic phosphate by using a form of energy. The key points of ATP synthesis are given below:

Protons are translocated across the membrane, from the matrix to the intermembrane space, as a result of electron transport resulting from the formation of NADH by oxidation reactions. (See the animation of electron transport.) The continued buildup of these protons creates a proton gradient.

ATP synthase is a large protein complex with a proton channel that allows re-entry of protons.

ATP synthesis is driven by the resulting current of protons flowing through the membrane:

ADP + Pi ---> ATP


About 200-300 moles of ATP are used daily by the average adult (A mole is a chemistry term meaning the amount of substance in a system that contains as many elementary entities as there are atoms in exactly 0.012 kilogram of carbon-12). The total quantity of ATP in the body at any one time is 0.1 mole.

This means that ATP must be recycled 2000-3000 times over the course of a day. ATP cannot be stored so its synthesis must closely follow its consumption.



The two stages of biosynthesis-the formation of building blocks and their specific assembly into macromolecules-are energy-consuming processes and thus require ATP. Although the ATP is derived from catabolism, catabolism does not "drive" biosynthesis. As explained in the first section of this article, the occurrence of chemical reactions in the living cell is accompanied by a net decrease in free energy. Although biological growth and development result in the creation of ordered systems from less ordered ones and of complex systems from simpler ones, these events must occur at the expense of energy-yielding reactions. The overall coupled ... (100 of 25244 words)

Explain the role of the nucleus and rough endoplasmic reticulum in protein synthesis

Role of nucleus:

The nucleus stores the cells DNA and coordinates the cells activites.

Role of endoplasmic reticulum:

Describe the process of spermatogenesis.

the overall result of spermatogenesis

1. The overall result of spermatogenesis:

a. Cell proliferation

i. More cells are produced than originally present

ii. Each spermatogonia may produce up to 256 spermatozoa per cycle (25 x 4)

b. Maintenance of a reserve germ cell population

i. Production of new spermatogonia is faster than maturation of spermatozoa

c. Haploid gametes are produced

d. Genetic variability is introduced

i. Independent assortment during meiosis

ii. Crossing-over during Prophase I of meiosis

e. Spermatids mature into spermatozoa

€±€®€¶€ € nalyse the principles of the cellular processes involved in growth and specialisation of cell structure and function, using the erythrocyte as an example.

2.1 Explain how different types of blood cells are adapted for their functions in the body.

Blood cells: erythrocytes, haemoglobin-oxygen dissociation; the Bohr effect, leucocytes and their role in the immune response; thrombocytes, blood clotting  

There are three types of blood cells in human body and they are:

Red blood cells/Erythrocytes'/ (RBC)

White blood cells/ Leucocytes (WBC)

Thrombocytes (Platlets)

Red blood cells/Erythrocytes' (RBC): These blood cells are seen in the surface which are rendered spherical by water, crenate by salt and do not normally occur in the body. The diameter of a typical human erythrocyte disk is 6-8 µm, much smaller than most other human cells. A typical erythrocyte contains about 270 million hemoglobin molecules, with each carrying four heme groups.

Role of Red blood cells/Erythrocytes': it performs one of the most important duties in the body. It absorbs and delivers oxygen through the bloods, removes waste and transports CO2 away from body. It also stores irons.

Bohr effect is a property of hemoglobin which states that in the presence of carbon dioxide, the oxygen affinity for dissociation hemoglobin, decreases; i.e. an increase in blood carbon dioxide level or a decrease in pH causes hemoglobin to bind to oxygen with less affinity.

This effect facilitates oxygen transport as hemoglobin binds to oxygen in the lungs, but then releases it in the tissues, particularly those tissues in most need of oxygen. The carbon dioxide is quickly converted into bicarbonate molecules and acidic protons by the enzyme carbonic anhydrase:

CO2+ H2O H+ + HCO3−

Leucocytes/white blood cells/(WBC):

White blood cells, or leukocytes, are cells of the immune system defending the body against both infectious disease and foreign materials. Several different and diverse types of leukocytes exist, but they are all produced and derived from a multipotent cell in the bone marrow known as a hematopoietic stem cell. Leukocytes are found throughout the body, including the blood and lymphatic system.

Role of leucocytes:

White blood cells are an important part of our body's immune system. Their role is to defend the body against infection by germs. These are capable of passing through the walls of capillaries (tiny blood vessels) in order to attack, kill and consume intruder germs. In conditions such as leukemia, the number of leukocytes is higher than normal, and in leukopenia, this number is much lower. The physical properties of leukocytes, such as volume, conductivity, and granularity, may change due to activation, the presence of immature cells, or the presence of malignant leukocytes in leukemia.

Thrombocytes/Platelets: these are other important part or component of your blood. Platelets are sticky little pieces that help prevent bleeding and make the blood clot when a cut is made.

When a stem cell decides to make platelets, it turns into a factory cell called a megakaryocyte. This is a very large cell with several nuclei. The megakaryocyte never leaves the bone marrow, but it does produce many, many tiny fragments. These fragments are actually the platelets, small pieces of cell material or cytoplasm.


Platelets do leave the bone marrow and circulate freely in the bloodstream.

€²€®€²€ …xplain how a range of epithelial tissues are adapted for their function in the body

Epithelial tissue covers the whole surface of the body. It is made up of cells closely packed and ranged in one or more layers. This tissue is specialised to form the covering or lining of all internal and external body surfaces. Epithelial cells are packed tightly together, with almost no intercellular spaces and only a small amount of intercellular substance. Epithelial tissue, regardless of the type, is usually separated from the underlying tissue by a thin sheet of connective tissue; basement membrane. The basement membrane provides structural support for the epithelium and also binds it to neighbouring structures.

Epithelial tissue can be divided into two groups depending on the number of layers of which it is composes. Epithelial tissue which is only one cell thick is known as simple epithelium. If it is two or more cells thick such as the skin, it is known as stratified epithelium.

Simple epithelium again divided into four groups and they are:

Sqaumous Epithelium

| Cubiodal Epithelium|

Columnar Epithelium|

Stratified Epithelium

Squamous epithelium: Squamous cells have the appearance of thin, flat plates. The shape of the nucleus usually corresponds to the cell form and help to identify the type of epithelium. Squamous cells, for example, tend to have horizontall flattened, elliptical nuclei because of the thin flattened form of the cell. They form the lining of cavities such as the mouth, blood vessels, heart and lungs and make up the outer layers of the skin.

Simple sqaumous epithelium

Simple Cuboidal Epithelium.

As their name implies, cuboidal cells are roughly square or cuboidal in shape. Each cell has a spherical nucleus in the centre. Cuboidal epithelium is found in glands and in the lining of the kidney tubules as well as in the ducts of the glands. They also constitute the germinal epithelium which produces the egg cells in the female ovary and the sperm cells in the male testes.

Simple cuboidal epithelium

Simple Columnar Epithelium

Columnar epithelial cells occur in one or more layers. The cells are elongated and column-shaped. The nuclei are elongated and are usually located near the base of the cells. Columnar epithelium forms the lining of the stomach and intestines. Some columnar cells are specialised for sensory reception such as in the nose, ears and the taste buds of the tongue. Goblet cells (unicellular glands) are found between the columnar epithelial cells of the duodenum. They secrete mucus or slime, a lubricating substance which keeps the surface smooth.

Simple columnar epithelium

Ciliated Columnar Epithelium

These are simple columnar epithelial cells, but in addition, they posses fine hair-like outgrowths, cilia on their free surfaces. These cilia are capable of rapid, rhythmic, wavelike beatings in a certain direction. This movement of the cilia in a certain direction causes the mucus, which is secreted by the goblet cells, to move (flow or stream) in that direction. Ciliated epithelium is usually found in the air passages like the nose. It is also found in the uterus and Fallopian tubes of females. The movement of the cilia propel the ovum to the uterus.

Ciliated columnar epithelium

Glandular Epithelium

Columnar epithelium with goblet cells is called glandular epithelium. Some parts of the glandular epithelium consist of such a large number of goblet cells that there are only a few normal epithelial cells left. Columnar and cuboidal epithelial cells often become specialised as gland cells which are capable of synthesising and secreting certain substances such as enzymes, hormones, milk, mucus, sweat, wax and saliva. Unicellular glands consist of single, isolated glandular cells such as the goblet cells. Sometimes a portion of the epithelial tissue becomes invaginated and a multicellular gland is formed. Multicellular glands are composed of clusters of cells. Most glands are multicellular including the the salivary glands.

Glandular epithelium

Stratified Epithelium.

Where body linings have to withstand wear and tear, the epithelia are composed of several layers of cells and are then called compound or stratified epithelium. The top cells are flat and scaly and it may or may not be keratinised (i.e. containing a tough, resistant protein called keratin). The mammalian skin is an example of dry, keratinised, stratified epithelium. The lining of the mouth cavity is an example of an unkeratinisied, stratified epithelium.

Stratified epithelium

Functions of Epithelial Tissue


Epithelial cells from the skin protect underlying tissue from mechanical injury, harmful chemicals, invading bacteria and from excessive loss of water.


Sensory stimuli penetrate specialised epithelial cells. Specialised epithelial tissue containing sensory nerve endings is found in the skin, eyes, ears, nose and on the tongue.


In glands, epithelial tissue is specialised to secrete specific chemical substances such as enzymes, hormones and lubricating fluids.


Certain epithelial cells lining the small intestine absorb nutrients from the digestion of food.


Epithelial tissues in the kidney excrete waste products from the body and reabsorb needed materials from the urine. Sweat is also excreted from the body by epithelial cells in the sweat glands.


Simple epithelium promotes the diffusion of gases, liquids and nutrients. Because they form such a thin lining, they are ideal for the diffusion of gases (eg. walls of capillaries and lungs).


Ciliated epithelium assists in removing dust particles and foreign bodies which have entered the air passages.

Reduces Friction

The smooth, tightly-interlocking, epithelial cells that line the entire circulatory system reduce friction between the blood and the walls of the blood vessels.


€ € € € € € € € € € € € €²€®€³€ € Explain how neurones are adapted for their function within body communication mechanisms.

A neuron is a cell specialized to conduct electrochemical impulses called nerve impulses or action potentials. Neurons (also known as neurones and nerve cells) are electrically excitable cells in the nervous system that process and transmit information.

Neurons are the core components of the brain, the spinal chord,and the peripheral nerves.

Neurons communicate through an electrochemical process. Sensory receptors interact with stimuli such as light, sound, temperature, and pain which is transformed into a code that is carried to the brain by a chain of neurons. Then systems of neurons in the brain interpret this information. The information is carried along axons and dendrites because of changes in electrical properties which we call action potential. An action potential is initiated when a messenger attaches itself to a receptor. When that occurs, an electrical signal is triggered to be generated through the neuron. Once the signal reaches the end of an axon, which is at the end of a neuron, a neurotransmitter is released and the process repeats.

Neurones have three major purposes:

1. to gather and send information from the senses such as touch, smell, sight etc.

2. to send appropriate signals to effector cells such as muscles, glands etc.

3. to process all information gathered and provide a memory and cognitive ability thus allowing us to take voluntary action on information received.

(more idea on lecture slide, week 3 slide 10….)

€²€®€´€ € …xplain how the structure and physiology of muscle cells relate to their role in the body

myofibril structure (actin, myosin, sarcolemma, myoglobin), contractility (twitch, summation, fatigue)

Muscle cells is an elongated contractile cell that forms the muscles of the body. There are two types of structure of muscle cells are they are:




Some of the components of skeletal muscle cells that are specific to muscle tissue are myofibrils.

Each muscle fibre ("muscle cell") is covered by a plasma membrane sheath which is called the sarcolemma.

Tunnel-like extensions from the sarcolemma pass through the muscle fibre from one side of it to the other in transverse sections through the diameter of the fibre.

These tunnel-like extensions are known as transverse tubules ("T Tubules") - not shown in diagram above.

The nuclei of muscle fibres ("muscle cells") are located at the edges of the diameter of the fibre, adjacent to the sarcolemma. As illustrated, a single muscle fibre may have many nuclei.

Cytoplasm is present in all living cells.

The cytoplasm present is muscle fibres (muscle cells) is called sarcoplasm.

The sarcoplasm present in muscle fibres contains very many mitochondria, which are the energy-producing units within the cell. These mitochondria produce large amounts of a chemical called "Adenosine Triphosphate", which is usually referred to in abbreviated form as "ATP". (The cellular activities for which ATP is required include contracting muscles, moving chromosomes during cell division, moving structures with cells, transporting substances across cell membranes, and synthesizing larger molecules from smaller ones. To understand the function of ATP for the actions of muscle fibres/cells, remember that ATP is necessary for muscle contraction, and is produced by the mitochondria within the muscle cell/s).

Sarcoplasmic reticulum is a network of membrane-enclosed tubules similar to smooth endoplasmic reticulum (SER). Sarcoplasmic reticulum is present in muscle fibres/cells and extends throughout the sarcoplasm of the cell. The function of the sarcoplasmic reticulum is to store calcium ions, which are necessary for muscle contraction.

Myoglobin is also present in the sarcoplasm of muscle fibres/cells. This is a reddish pigment that not only results in the distinctive colour of skeletal muscle, but also stores oxygen - until it is required by the mitochondria for the production of ATP.

The components of skeletal muscle cells that are specific to muscle tissue are called myofibrils.

These are cylindrical structures (illustrated above) that extend along the complete length of the muscle fibre/cell.

Each myofibril consists of two types of protein filaments called "thick filaments", and "thin filaments".

These two types of filament have different structures - as illustrated on the page about labeled diagrams of muscle filaments.

Here, it is sufficient to say that the thick filaments and the thin filaments within myofibrils overlap in a structured way, forming units called sarcomeres.

Contractility: summation, twitch and fatigue are the three conditions of muscle cells. In a relaxed muscle, thick and thin myofilaments overlap each other a tiny bit. When a muscle cell is stimulated by a nerve impulse, these myofilaments slide past each other until they completely overlap. This makes the muscle cell shorter and fatter. The more shortened muscle cells there are in a muscle, the greater the contraction of the muscle as a whole.

Question 3: In this section you should explain the physiological mechanisms involved in key activities of the body in relation to relevant tissues, organs and body systems

Maintenance of balance: role of visual and balance sense organs, proprioreceptors, reflexes  Musculo-skeleta system and co-ordination: articulation of bones in relation to movement, antagonistic and synergistic muscle action, reflex actions, role of nervous system  Alimentary canal: digestive and absorptive functions; role of liver, pancreas; egestion of residues  Excretory processes and interrelationships: role of blood, pulmonary, liver and renal excretory mechanisms

3.1 Describe how the body maintains balance.

Maintenance of balance: role of visual and balance sense organs, proprioreceptors, reflexes  Musculo-skeleta system and co-ordination:

€³€®€²€ …xplain how co-ordinated musculo-skeletal movements are produced

articulation of bones in relation to movement, antagonistic and synergistic muscle action, reflex actions, role of nervous system 

According to….,co-ordinated musculo-skeletal movements are produced by articulation of bones, antagonistic and synergistic muscle action, reflex actions, the role of nervous system.

Articulation of bones: Articulation is a point of contact between bones, between cartilage and bone, or between teeth and bones. Different types of movement can be produced from articulation of bones such as gliding movement, angular movement, circular movement, special movement etc.

Gliding movements occur when one surface moves back and forth and from side to side over another surface without angular or rotary motion.

Examples: Joints between carpals and between tarsals.

Angular movements occur when angle of bone increases or decreases. Rotational motion is another type of movement and it occurs when a bone turns around its own axis. For example, atlanto-axial joint, pronation and supination.


Skeletal muscles, attached to bone by tendons, produce movement by bending the skeleton at movable joints. The connecting tendon closest to the body or head is called the proximal attachment: this is termed the origin of the muscle. The other end, the distal attachment, is called the insertion. During contraction, the origin remains stationary and the insertion moves.

The force producing the bending is always exerted as a pull by contraction, thus making the muscle shorter: Muscles cannot actively push. Reversing the direction in which a joint bends is produced by contracting a different set of muscles. For example, when one group of muscles contracts, an antagonistic group stretches, exerting an opposing pull, ready to reverse the direction of movement.

The contracting unit is the muscle fiber.  Muscle fibers consist of two main protein strands - actin and myosin. Where the strands overlap, the fiber appears dark. Where they do not overlap, the fiber appears light. These alternating bands of light and dark give skeletal muscle its characterisitc striated appearance.  The trigger which starts contraction comes from the motor nerve attached to each muscle fiber at the motor end plate.

Acetylcholine is released at the motor end plate when the electrical impulse reaches the muscle fiber. As it binds to receptors on the surface of the muscle cells, it causes the electrical impulse to be transmitted in both directions along the fiber, activating the actin and myosin strands. The strands slide past each other to flex, or to shorten, the fiber, thus producing contraction

Nervous system has also a role to play for the of musculo-skeleton movement. (how nervous system is responsible for musculo skeleton movement, idea from lectures)

€ € € € € € € € € € € € € €³€®€³€ nalyse how the stomach, small and large intestines are adapted for digestion and absorption of food.

Digestion is the mechanical and chemical breaking down of food into smaller components that can be absorbed into a blood stream, for instance. Digestion is a form of catabolism: a break-down of larger food molecules to smaller ones. Digestion starts from the mouth and finishes at large intestine but the major digestion starts from the stomach. The digestion processes are described below from the stomach.

Stomach is located on left side of abdominal cavity, right below diaphragm. It stores food (can stretch to accommodate up to 2 liters of food and water), and breaks it down with acids and enzymes. Firstly, stomach secretes gastric juice that contains hydrochloric acid (HCl), enzymes (pepsin), and mucus. It helps to break down the bolus into a liquid is called chyme. Then digestion of protein starts in stomach with pepsin. Food remains in stomach from 2 to 6 hours, after which it is released into the small intestine.

Small intestine is a huge surface area, about 300 square meters where most digestion and absorption occurs.

Bile from the gallbladder and enzymes from the pancreas and intestinal walls combine with the chyme to begin the final part of digestion. Bile liquid is created in the liver and stored in the gallbladder. Bile emulsifies (breaks into small particles) lipids (fats), which aids in the mechanical digestion of fats. The pancreas and gland cells of the small intestine secrete digestive enzymes that chemically break down complex food molecules into simpler ones. These enzymes include trypsin (for protein digestion), amylase (for carbohydrate digestion), and lipase (for lipid digestion). When food passes through the duodenum, digestion is complete.

Pancreas and liver empty digestive enzymes and bile into the small intestine.

Pancreatic amylase: Breaks down starch

Trypsin and Chymotrypsin: Break down proteins

Lipases: Break down fats

Peptidases: Break down proteins

Nucleases: Break down DNA and RNA

Bile: Helps fat digestion by emulsifying fats.

Very large surface area for absorption due to:

Large circular folds (villi)

Tiny cell surface projections (microvilli).

Capillaries drain nutrients from small intestine and then sends them to first to liver and then rest of body.

Food inters in the large intestine/colon after finishing the digestion process in small intestine which is 1.5 m long and 5 cm wide (diameter). Most water absorption occurs here (up to 90%). Finally, feces (undigested waste products) are carried to the rectum through peristalsis and eliminated through the anus.

Undigested remainder of food is converted into feces.

Site of bacterial synthesis

Vitamin K

Folic acid


Several B vitamins

€ € € € € € € € € € € € € €³€®€´€ Explain the roles of the blood, lungs and kidneys in body excretory processes and their


The job of the excretory system is to remove various produced by the body. The removal is known as excreation. It is important for the body to remove these various waste, also known as toxic, because toxic build up can lead to servere death.

About sixty percent of your body contains water. A portion of the water is in the tissues and cells. The water contains salt. the salt needs to be kept at the right concentrations. If there is little salt the body feeds it more, if there is too much salt the body gets rid of the salt not needed. This is the task of the two Kidneys.

The liver acts as a filter for the blood. It cleans out toxic waste and acid in the blood.

Question 4: In this section you are expected to analyse how body functions are regulated within normal limits 'with reference to either primary or secondary source data'

€ € € € € € € € €´€®€± Analyse how feedback mechanisms operate to regulate metabolic processes

Feedback is a mechanism, process or signal that is looped back to control a system within itself.

Feedback mechanisms operate to regulate processed by different types of interactions like negative interaction, positive interaction, neural and endocrine interactions, tissue behaviour or effects on cell (e.g. concentration gradients, membrane permeability, enzymatic reactions). It has three part and they are:

The receptor (receives information of something from the environment)

The control center (receives and processes information from the receptor)

The effector (responds to any command by either opposing the or enhancing the stimulus)

Metabolic processes can be regulated by positive both feedback and negative feedback which are shown below:

Positive feedback:

A response to amplify the changes in the variable

This has a destabilizing effect and does not result in homeostasis

Positive feedback is less common in naturally occurring systems than negative feedback. For example , in nerves, a threshold electric potential triggers the generation of a much larger action potential

Another example of positive feedback is blood clotting

Clotting occurs as a result of sequential activation of clotting factors. Activation of one clotting factor results in activation of many in a sequential cascade

Negative feedback:

A reaction in which the system respond in such a way as to reverse the direction of change.

Since this tends to keep things constant , it allows maintenance of homeostasis, e g when the concentration of carbon dioxide in the human body increases, the lungs are signalled to increase their activity and expel more carbon dioxide.

In order for internal consistency to be maintained , the body must have sensors that are able to detect deviations from a "set point".

A "set point" is analogous to the temperature in a house thermostat. if you set your thermostat at 20 degrees C (set point) , the thermometer in the thermostat senses any temperature change either too high or too low ,and sends messages to the "control center" (thermostat) ,which will then send a massage to the boiler to shut down or start depending on the temperature . This is an example of negative feedback.

If the body temperature exceeds the set point of 37 degrees C , sensors in a part of the brain detect this deviation and acting via a integration center (also in the brain) stimulate activities of the effectors (including sweat glands) that lower the temperature.

The negative feed back loops are continous , ongoing processes.

Endocrine system:

The endocrine system consists of glands which secrete hormones into the blood stream

Each hormone has effect on one or more target tissue

In this way the endocrine system regulates the metabolism and development of most body cells and body systems e g the endocrine system has sex hormones that can activate sebaceous glands, development of mammary glands, alter dermal blood flow and release lipids from adipocytes.

Our bone growth is regulated by several hormones ,and the endocrine system helps with the mobilization of calcitonin and calcium.

In the muscular system, hormones adjust muscle metabolism, energy production, and growth.

In the nervous system, hormones affect neural metabolism, regulate fluid/electrolyte balances and help with reproductive hormones that influence CNS development and behaviours.

4.2 Explain regulatory mechanisms involved in cardiovascular and respiratory functioning

Autonomic nervous system, erythrocytes, medulla, blood plasma, chemoreceptors are involved in cardiovascular and respiratory functioning. These are explained below:

The nervous system, along with the endocrine system , serves as the primary control centre of the body working below the level of consciousness

The hypothalamus of the brain is where the body's "thermostat" is found

Hypothalamus also stimulates the pitiutary gland to release various hormones that control metabolism and development of the body .

It also controls contractions like the arrector pili muscles (involved in thermo regulation) and skeletal muscles.

The nervous system also regulates various systems such as respiratory (controls pace and depth of breathing) , cardiovascular system (controls heart rate and blood pressure) ,endocrine organs (cause secretion of ADH and oxytocin) ,the digestive system(controls digestive tract movements and secretions) and the urinary system (it helps to adjust renal blood pressure and also control voiding the bladder)

Respiratory system:

The respiratory system works in conjunction with the cardiovascular system to provide oxygen to cells within every body system for cellular metabolism

The respiratory system also removes carbon dioxide

Since CO2 is mainly transported in the plasma as bicarbonate ions, which act as chemical buffer

The respiratory system works in conjunction also helps maintain proper blood ph levels a fact that is very important for homeostasis.

As a result of hyperventilation , CO2 is decreased in blood levels. This causes the ph in the body fluids to increase. If acid level rise above 7.45, the result is respiratory alkalosis

Too much CO2 causes the ph to fall below 7.35which result in respiratory acidosis

The respiratory system also helps the lymphatic system by trapping pathogens and protecting deeper tissues within

€ € € € € € € € €´€®€³€ …xplain the hormonal regulation of fat and carbohydrate metabolism

Energy metabolites: carbohydrates, peptides in energy metabolism and lipids; insulin, glycogen, adrenaline

€´€®€´€ Compare the roles of the hypothalamus and skin in thermoregulation

Thermoregulation: heat loss: skin, surface area, sweat; thermogeneration, role of thyroxine Data: haematological, biochemical, respiratory and cardiovascular measures Lifestyle/environmental factors: temperature, pollution; diet, active/sedentary lifestyle, substance use (***)

Skin in thermo regulation

4.5 Use the data and the tables below to explain how lifestyle and environmental factors impact on body

weight and cardiovascular regulation :