Topic 7

• Epidermis • Dermis • Fat • Glands • Hair follicles

• Regulation of body temp • Protection and immunity • Sensation • Excretion • Synthesis of vitamin D

In hot weather, there is an increase in blood flow to the skin. There is an increase in sweat production by the sweat glands. Evaporation of sweat cools the skin which leads to a decrease in body temp

Proection of underlying tissue against impact, abrasion, fluid loss, harmful chemicals

Detecting touch, pain, pressure, and temperature stimuli through nerve endings and receptors to the skin. This info is relayed to the nervous system

Exertion of salt, water, and organic wastes by integumentary glands

When exposed to sunlight, epidermal cells produce vitamin D. Which is important in absorption of calcium (promoting bone growth and muscle contraction)

• Brain stem • Diencephalon • The two hemispheres of the Cerebrum • Cerebellum

• Frontal • Pariental • Occipital • Temporal • Limbic

Blood supply to the brain comes form the aortic arch in the heart. RIGHT SIDE: - The brachiocephalic trunk : splits inyo the righter internal and external artery: LEFT SIDE: - Left carotid artery: splits into internal and external arteries Internal= enters the skull and suppliers the anterior part of the brain ( via the cerebral branches) the eye and its appendages and sends branches to the forehead and nose. External= Flows upwards on the side of the head to branch into various structures in the neck, face, jaw, scalp, and base of skull. Blood-brain barrier A nertwork of blood vessels that allows the entry of essential nutrients into the brain and blocking other substances (toxins and bacteria) that could injure the brain if entering. - Small compounds such as antidepressents, anti-anxiety meds, alcohol, cocain, and many other hormones can go through the endothelial cells (nake up of blood-brain barrier) without much effort - Large molecuels (glucose, insulin) must be ferrier across by proteins. Soluable molecules cant travel into the brain.

The brain obtains energy using glucose and oxygen, which passes rapidly from blood to braincells. Glucose and oxygen are used to make ATP in the brain by the process of aerobic respiration. Carbohydrates stored in the brain are limited, therefore, glucose supply needs to be continous. - If blood entering the brain has low glucose or oxygen levels an individual may experience confusion , dizziness, loss of consciousness

• The autonomic cardiovascular and respiratory control centre and found in brainstem (medulla oblongata) • Control of breathing rate and depth, heart rate, and blood pressure • Chemoreceptors in the aorta detect change in blood pH or changes in blood pressure

• Helps smooth and coordinate muscle contractions • Regulate posture and balance • Makes possible all skilled motor activities (catching a ball, dancing)

THALAMUS: perception of sensation (pain, temp, touch) and relays info to the cerebrum HYPOTHALAMUS: Control of the autonomic nervous system. Adjusts and coordinates autonomic nervous system in the brain stem to regulate heart rate and blood pressure. - Regulates hormones released from the pituitary gland - Appetite and thirst - Regulates body temp - Fluid and electrolyte balance - Circadian rhythms

Frontal lobe: Reasoning, motivation, planning, emotions, problem solving, speach, movement motor areas Pariental lobe: Movement, body awarness, orientation, navigation Occipital lobe: visual sensory, association area: many aspects of long term and visual memory Temporal lobe: auditory sensory and association Limbic lobe: Association process: emotions, behaviour, motivation, long-term memory