The Hypothalamus The hypothalamus and the pituitary glands are neuroendocrine organs. The hypothalamus is found in the central part of our brain, in the middle of the pituitary and pineal gland. It regulates our metabolism, blood pressure, fluid balance, and body temperature. It does this by sending signals (stimulating hormones) to the pituitary gland, to release, …
Major Role The main role of the endocrine system is to send chemical messages (stimulating hormones); the chemicals are secreted directly into the circulatory system to target organs. It also runs in unison with the nervous system, these chemical messages help control physiological processes, such as nutrient absorption, growth, etc. Major organs/glands Many glands exist in the …
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Lymphatic ducts There are two main lymphatic ducts: The right lymphatic duct and the left lymphatic duct. Right lymphatic duct The right lymphatic duct drains the right arm, shoulder area, the right thorax, the right side of the head and neck. Left lymphatic duct (Thoracic duct) The left lymphatic duct is the biggest lymph vessel, …
Major Role The main role of the lymphatic system is to produce antibodies for the destruction and removal of invading bacteria and viruses, to prevent infection, to filter and clean lymph, to remove fat and excess fluids (to control oedema) from the blood. Major Components Lymph, lymph nodes, and vessels, tonsils, thymus, subclavian veins, spleen, intestinal …
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Blood Vessels – The main types of blood vessels are: Arteries, Arterioles, Capillaries, Venules, and Veins Blood Vessels Structure Function Arteries Thicker muscular walls (outer structure) of arteries contain smooth muscle fibres that contract and relax under the instructions of the sympathetic nervous system. Transport blood away from the heart; Transport oxygenated blood only (except in the …
Blood Consists of red blood cells & white blood cells Cells make up approx. 45% of the whole blood 55% of blood is plasma, a yellowish fluid Function of Blood Transports oxygen, nutrients, and waste around the body Regulation of water and temperature in the body Protection against blood loss (haemorrhaging), by clotting, & defends the body against …
Major Role The main role of the circulatory/cardiovascular system is to transport nutrients, gases (such as oxygen and CO2), hormones, and wastes through the body. Major Components Heart, blood vessels, and blood.
Body Area % Telogen hairs (resting phase) % Anagen hairs (growing phase) Resting time in Telogen Growing time in Anagen Approx. depth of terminal Anagen follicle Top lip 35 65 6 weeks 3 months 1 – 2.5mm Chin 20 70 10 weeks 1 year 2.4mm Cheeks 30-50 50-70 – – 2.4mm Eyebrows 90 …
Types of Hair There are 4 types of hair found on the body Lanugo hair Fine, soft, without a medulla, and un-pigmented Found in foetal life Is shed around the 7th or 8th month of pregnancy Vellus hair Soft, fine, downy, and un-pigmented Found all over the body except the lips, genitals, palms of hands, …
The Hair Growth Cycle The hair has a repeated pattern of growth which can be classified into four stages. Anagen – the anagen is the active growth stage of the hair. The cells of the germinal matrix are in close contact with the blood supply from the dermal papilla. This enables them to divide; and form new …
Hairs are long slender structures, composed of dead epithelial cells and keratin, which grows from follicles in the skin. They cover the whole body, with the exception of the palms of the hands, soles of the feet, lips, and the sex organs. The hair has many functions Scalp hair insulates the head against cold, protects …
Medulla Is the central core of hair which is present, in all, but the finest of hairs. The cells of the medulla contain soft keratin, and occasionally, granules of pigment, which give the hair its colour (or pigmentation). When this pigment is absent, the hair appears white. Cortex The cortex is the thickest part of the hair …
Functions of the Skin ‘SHAPESS’ 1) Secretion Sebum – (sebaceous glands) Sweat – (sudoriferous glands) Sebum produced from the sebaceous glands and sweat combine to form an acidic film on the skin surface known as acid mantle, this creates a protective layer. 2) Heat Regulation – this skin function regulates the body’s temperature …
Appendages of the skin Sweat glands – apocrine and eccrine sweat glands Apocrine glands produce smelly sweat – ‘O’ for Odour – and are found in the underarm, groin, and middle of the chest Eccrine glands – non-odoriferous sweat glands that produce sweat to cool, and regulate, the body’s temperature
The subcutaneous layer/hypodermis The subcutaneous layer is the layer of fat found under the dermis The cells of the subcutaneous layer are known as adipose tissue (fat) The subcutaneous layer is deeper in some regions of the body than others and varies from person to person The functions of the subcutaneous layer/hypodermis Storage – it …
The Layers of the Dermis The papillary layer – this is the upper layer of the dermis and is a row of ridges that attaches the dermis to the epidermis The reticular layer – this is the deep layer of the dermis and is often known as the true skin. It contains collagen fibres that give the …
The Epidermis has 5 layers Stratum Corneum (Horny Layer) Stratum Lucidum (Clear Layer) Stratum Granulosum (Granular layer) Stratum Spinosum (Prickle cell Layer) Stratum Germinativum (Basal layer) A detailed look at the Epidermis Stratum Corneum (Horny Layer) The layer that can be seen and felt Several layers of flattened, dead, overlapping, scale-like cells – mainly composed of a protein called …
There are 3 sections in the skin Epidermis Dermis Subcutaneous layer/hypodermis
