BIO FINALS

• Integumentary System

  • outermost layer of the body
  • skin, hair, nails, and the glands along with the nerves
  • body's defense against harm
  • helps regulate body temperature
• Epithelial Tissues

  • found in the epidermis
  • made up of stratified squamous epithelia
• Connective Tissue

  • found in the dermis
  • consists of areolar and dense irregular connective tissue and histiocytes (tissue macrophages)
• Subcutaneous / Adipose Tissue

  • found in the hypodermis
  • includes areolar connective tissue, adipose tissue, and glands
• Adipose Tissue

  • insulation (heat)
  • cushions (protection)
• Homeostasis - internal balance
• Hair shaft - part of hair that can be seen, touched, and styled
• Hair follicle - keeps hair in the skin
• Hair bulb - responsible for hair growth
• Arrector Pili Muscle - Muscle that CONTRACTS to make hair stand up.
• Skin

  • largest & heaviest organ
  • thinner on eyelids and face
  • thicker on the soles of feet
• Stratum Corneum

  • top, oldest and visible layer
  • where keratinocytes become corneocytes (act as protection)
  • has fats that prevent water from easily entering
• Stratum Lucidum

  • thin, transparent layer of keratinocytes
  • divides dead and living cells
• Stratum Granulosum

  • granulated keratinocytes
• Stratum Spinosum

  • living keratinocytes (youngest layer)
  • includes sticky proteins called "Desmosomes" which holds keratinocytes together
  • helps make your skin flexible and strong
• Stratum Basale

  • melanocytes, newly developed cells
  • deepest layer
  • where new skin cells develop
• Melanocytes

  • melanin
  • gives us tan skin color
• It take 2-4 weeks to shed skin
• Langerhans cells

  • outermost guard of the cutaneous immune system
• Dermis

  • middle and thickest layer
  • thinnest - eyelids
  • thickest - back
  • produces sweat, keeps skin moist
  • producing hair - collagen
• Elastin

  • protein responsible for elasticity
• Outer Papillary Dermis

  • form a strong bond that connects
  • contains the receptors
• Phagocytes

  • cells that fight bacteria
• Mechanoreceptors

  • respond to physical changes (touch, pressure, vibration, and stretch)
• Thermoreceptors

  • display a constant discharge to their specific temperature
• Nociceptors

  • helps signal pain
• Pacinian corpuscles

  • detect light touch
• Meissner corpuscles

  • dermal papillae
  • detect vibration
• Merkel corpuscles

  • understanding the structure and texture
• Ruffini corpuscles

  • detects stretch
• Inner Reticular Layer

  • surrounded by a net-like structure of elastin fibers and collagen fibers that support the skin's overall structure
• Glands

  • release water, salt or oil from under the skin to the surface of the skin
• Sebaceous glands

  • secretes keratin and sebum
• Sudoriferous glands

  • secretes sweat
• Eccrine sweat

  • found all over the body
• Apocrine sweat

  • attached at the follicle hair
  • smelly sweat
• Ceruminous glands

  • secretes wax
• Mammary glands

  • secretes milk
• Hypodermis

  • subcutaneous layer
  • insulation and cushion
  • thinnest - eyelids and external genitals
  • thickest - abdomen and butt
• Skeletal System

  • framework of the body
  • consisting of bones and other connective tissues