Basic intro to the body Flashcards
Function of skin
Protects against germs, regulates temperature and enables touch
Structure of skin
Has an epidermis, a dermis and subcutaneous tissue
Describe the epidermis
Has a keratinised epithelium, some nerve endings and is avascular
Describe the dermis
Collagenous and elastin rich, tough and stretchy, vascular and innervated. Contains hair follicles and some sweat glands
Describe the subcutaneous tissue
Adipose tissue (fat) store, vascular, innervated, contains sweat glands
Eccrine sweat gland
Water and some electrolytes, present on almost all skin
Apocrine sweat gland
Lipid/protein rich secretion, select sites activate with puberty
Axial skeleton
Skull, vertebrae, sacrum, ribs, coccyx, hyoid, sternum
Appendicular skeleton
Limbs, clavicle, scapula and hip bones
Function of nervous system
Senses and responds to external and internal stimuli
What are neurons
The functional cells of the nervous system conducting small electrical signals based on charge differences across their membranes. Communicate via neurotransmitter releases at synapses
What is a glial cell
Support neurons
What is a ganglion
A collection of cell bodies. Ganglia are sites of synapsing
What is in the CNS
Brain and spinal cord, covered in protective layer of meninges
What is the dura matter
The tough outer layer
What is the arachnoid matter
Middle layer, creates a subarachnoid space for cerebrospinal fluid
What is pia mater
Closely adhered to brain/spinal cord
What is in the PNS
31 paired spinal nerves, 8 cervical, 12 thoracic, 5 lumbar, 5 sacral, 1 coccygeal
What do the spinal nerves serve
Dermatomes (sensory) and myotomes (motor)
What are the 12 cranial nerves function
They arise from the brain/brainstem. Their functions mostly occur in head and neck, with exception of vagus nerve (CNX). Sight, smell, taste, hearing, balance
What is the ANS
Autonomic nervous system. Sympathetic=fight or flight
Parasympathetic=rest and digest
How do body cavities form?
From the trilaminar disc (ectoderm, mesoderm, endoderm). Endoderm is pinched off to form the GI tube. There is cephalo-caudal folding (folding in 2 directions). Lateral folds close the body wall and enclose the body cavities.
What are the 3 potential spaces
Cavities represent potential spaces - sources of infection spread, fluid build up/loss. The pericardium (around the heart), the pleural (lungs) and the peritoneal (GI tracks)
What lines the cavities
Lubricating fluid in between on the visceral (organ) and parietal (body wall) surface
What forms visceral and parietal membranes/layers
Structures invaginate into “balloons” of serous, slippery membranes, creating the layers. The potential space is lubricated
