Lecture 1 Exam Flashcards
Chemical Level of the Human Body
atoms: basic unit of a chemical
ex: oxygen
What are the 4 most common atoms in a person?
Carbon, Hydrogen, Oxygen, and Nitrogen
Cellular Level of the Human Body
smallest unit of life
How many cells in average human body?
30-40 trillion cells
Tissue Level of the Human Body
group of cells with a common function
4 main tissue types
epithelial, connective, nervous, and muscle
Organ level of the Human Body
group of organs working together
-perform major A or P function
Organism level of the Human Body
YOU
What type of chemical bonds are most common?
Hydrogen and Covalent bonds are most common, less likely ionic bonds
Maintenance of Boundaries
separating external and internal environments
External environment
anything not crossed a body barrier
ex: membrane, skin, blood
keep in: nutrients, water, heat
Internal environment
anything inside
ECF, plasma, ICF
keep out: pathogens, toxins/chemicals, UV radiation
metabolism
breaking down nutrients getting those into a cell, building product
Catabolism
-breakdown
-exergonic (releases energy)
Anabolism
-building up
-endergonic (requires energy)
Movement
-macro scale
-micro scale: movement of blood, air, digesta
Development and growth
-begins at conception: continues until death
Development
-differentiation of stem cells into body or somatic cells
-repair of cells
-replacement of cells
Growth
-hyperplasia: increase in number of cells
-hypertrophy: increase in cell size
Responsiveness
-ability to sense and respond to the environment
External: reflex due to skin burn
Internal: low blood sugar causes breakdown of glycogen
Reproduction
-continuing of species
-sexual reproduction
➼genetic diversity
What should be kept external to the human body?
-pathogens, toxins, UV radiation, debris, Nitrogen gas, acids/bases
O2 and atmospheric gas
-o2 is 21% of atmospheric gas
-true all over surface of gas
-humans most efficient at attaining o2 at sea level
Cells use what to create ATP
o2
Macronutrients
-carbs, lipids, proteins, water
Which macronutrients are ATP yielding?
carbs, lipids, proteins
Micronutrients
-vitamins, minerals
Overconsumption of nutrients leads to:
-obesity
-type 1 diabetes
-cardiovascular disease
Malnourishment leads to:
-lack of growth
-structural defects
-disease susceptibility
Atmospheric pressure
-atmospheric gases create ‘colum’ of air that pushes down on our bodies
-at sea level, this column is larger and helps drive air into our lungs
Temperature for ambient temps
-humans can only tolerate narrow range
Homeostasis
maintenance of internal environment despite changing external environments
Internal environments
-ECF (extracellular environment)
-blood pressure
External environments
-anything outside of an epithelial wall
➼lumen of GI tract
➼lumen respiratory tract
Regulated Physiological Variable
-sensed, monitored, and adjusted constantly
-kept in strict range
➼ ECF
Nonregulated Physiological Variable
- cannot be sensed directly and not kept in strict range
-can fluctuate widely
➼heart rate
➼ respiratory rate
Negative Feedback
-works to return a variable back to acceptable range
➼ EX: shivering, sweating
Positive Feedback
-works to keep a variable outside of its range (for short period time)
➼ EX: pregnancy
Positive Feedforward
- powerful and not common
-anticipatory mechanism which blunts physiological disruptions
➼ EX: track runner about to race
Effector
-anatomical, physical structure
Physiological Response
-what is going to happen due to effects
Serous membranes
-specialized membranes surrounding organs of the thoracic and abdominal cavities
Purpose of serous membranes
-surrounds organ, provides protection, and fluid protection
Cell membrane
-Fluid Mosaic Model
➼flexible,lots of stuff
Purpose of Cell Membrane
-separates ECF from ICF
Phospholipids
-forms barrier between two aq solutions
-physiological significance: provides selective permerability
Amphipathic nature
capable of interacting w H2O and charged molecules on surface but repel these items should they attempt to enter membrane
Cholesterol
-major membrane component
-at most temps, they function to enhance membrane fluidity
-where does this cholesterol come from?
➼ LIVER
➼ and the DIET
Glycoprotein
- similar to glycolipids
-glycoproteins have protein component within cell membrane and as carb component extending outward into ECF
Proteins
-membranes contain both peripheral and integral membrane proteins
Peripheral membrane
loosely bound to outer or inner leaflet of membrane
Integral membrane
span both sides of membrane; has an ECF and ICF face
Movement across membrane
-must be controlled and regulated for cell survival
-ECF and ICF cannot equilibriate
Passive Movement
-no ATP required
-concentration gradient required
Simple diffusion molecules
-PASSIVE MOVEMENT
-pass through membrane unaided (no help needed)
- o2, co2, n2
Facilitated diffusion molecules
-PASSIVE MOVEMENT
-requires protein channel
➼ large molecules
➼ polar charge
➼ h2o
Osmosis/diffusion of h2o
-PASSIVE MOVEMENT
-h2o can move unaided or with help of aquaporin
➼ H2O
Active Movement
- ATP required directly or indirectly
Primary Active Transport
-use proteins that can hydrolyze ATP
➼pumps
➼Na/K pump
➼ Ca2+ pump
➼ H+ pump
Secondary Active Transport
-work of pumps and establishes a gradient
-drags into/out of cell
Symport (SAT)
-two or more items at same time or same direction
Antiport (SAT)
-two or more items across membrane going in diff directions
Endocytosis and Exocytosis
-uses ATP to bend membrane and move items
➼endo: outside to in
➼exo: inside to out
Phagocytosis
-digests things that aren’t supposed to be there
Pinocytosis
-cell drinking (small molecules)
Secretion
-getting things out of cell
Cytoplasm
-gel like composition; houses and suspends organelles
➼ cytosol: water portion of cytoplasm (ICF)
Organelle
Membrane bound structure; carries out specific cell functions
Cytoskeleton
-provides structural support
-route of intra-cellular transport
-used during cytokinesis
3 types of filaments
-microtubules
-intermediate filaments
-microfilaments
Cytoplasm
-organelles and cytosol
-permits diffusion; osmosis
Golgi
-flattened membrane-like sacs
-functions to process, sort, or package proteins and lipids
Rough ER
-membrane extends from and is continuous w/ nuclear membrane ribosomes on surface functions to process proteins
Smooth ER
-lacks ribosomes on surface
-functions to produce lipids, phospholipids and steroid hormones
Mitochondria
-ATP production
-Mitochondria size and shape can change
Lysome
-digests old cellular components, bacteria
-low ph; 5
Nucleus
- houses DNA: stored as chromatin for majority of cell’s life
-facilitate Tc and mRNA processing
-contains nucleolus which produces ribosomal subunit B
-surrounded by a double phospholipid bilayer; nuclear pores provide exit/entry routes
Tissues
-groups of cells working together to accomplish common goal
Embryonic Development of Tissues
-First 8 weeks past conception, after this; embryo is fetus
Gastrulation
-embryo transforms from simple layer of cells into multi-layered structure
Ectoderm
- gives rise to epidermis, skin appendages, nervous system, pituitary
Mesoderm
- gives rise to CT: most bones and muscle
Endoderm
- gives rise to: lining of GI tract. lining of respiratory tract, liver, gall bladder, pancreas, lungs
Epithelial Tissue Main Functions
-covering and lining:
➼outer barrier
➼ protecting
➼ glandular:
➼exocrine
➼endocrine
Locations of Epithelial Tissue
-epidermis
- lining of GI tract, lining of resp. tract
-forming exocrine/endocrine glands
Connective Tissue Main Functions
- Support and Framework:
➼cartilage, bone, collagen
-Connect nutrients with cells
➼blood, adipose
Locations of Connective Tissue
- Dermis and hypodermis
-skeleton
-varied
Muscle Tissue (Smooth) Function
Muscle Tissue (Cardiac) Function
Muscle Tissue (Skeletal) Function
Location of Smooth Muscle Function
Location of Cardiac Muscle
Location of Skeletal Muscle
Nervous Tissue Functions
-sensation: input
-integration: brain, spinal cord
-activation: motor output
Nervous Tissue Locations
- CNS: Brain and Spinal Cord
- PNS- all other neurons
Integumentary
-SKIN
-one of the largest and heaviest organ systems
What does Integumentary system house?
- Houses; variety of cells: keratinocytes, fibroblasts, adipocytes
➼skin appendages: follicles, glands
➼ vessels: blood, lymph
What does Integumentary system produce?
-structural proteins: keratin
- lipids: surface
- antimicrobial compounds
- sweat: eccrine, apocrine
- sebum
-hormones: vit-D
Integumentary system contribution to homeostasis
- thermoregulation: evaporative cooling, shunt? blood, adipose
- blood calcium maintenance: keep blood Ca2+ within st. range
Common cells of integumentary system
- keratinocytes: 90% of epidermis
- fibroblasts: main cell dermis
- adipocyte: main cell hypodermis
Function of Epidermis
- Protection: abrasion/cuts, UV radiation, pathogens
- Desiccation: loss of body water ➼ insensible water loss
Structure of Epidermis
- made of 4-5 strata (layers of cells)
-constantly renews itself - avascular: NO VESSELS (blood or lymph)
- most cells are keratinocyte
- others are: stem cells, melanocytes, langevans, merkels
Dermis
-resides below or deep to epidermis
Function of dermis
-provides support and nutrients to epidermis
- houses skin appendages
- highly vascularized (lots of blood flow)
➼the blood vessels feed the dermis
Structure of Dermis
-papillary layer: loose aveolar, CT
➼protects superficially to form dermal papillae
➼ only accounts for about 10% of dermal thickness
➼ contains numerous capillaries
-reticular layer: dense irregular CT
➼spans distance below papillary layer and hypodermis
➼ contains larger vessels
➼ numerous sensory neuron endings (nociceptors: pain)
➼ most skin appendages found here
Hypodermis
resides below or deep to dermis
Function of Hypodermis
- protection: cushioning
- nutrient reservoir: most ATP from fat, dehydrated
- thermoregulation
Structure of Hypodermis
- loose aveolar CT w/ adipocytes
➼ WAT: white adipose tissue; stores triglycovides? lipid droplets
➼ BAT: brown adipose tissue; thermogenic
Distribution of Hypodermis
- always found between dermis and underlying structures such as bone or muscle
- amount reflects nutritional plane (calorie intake) and sexual characteristics
Skeletal System Functions (Structural)
- support against gravity
- attachment site for tendons and ligaments
- protect delicate viserca
Skeletal System Functions ( Homeostatic Contributions)
- mineral reservoir: Ca2+ especially important
‣ Ca2+ can be removed or deposited (takes time)
‣ short term is through kidneys
-blood cell production
‣ RBCs, WBCs, platelets - fat storage
Red Blood Cells
- aka erythrocytes
Long bones
- appendicular skeleton
‣ important for locomotion
‣ larger marrow cavity
Short bones
- appendicular skeleton
‣ important for stability during locomotion
Flat bones
- axial skeleton
‣ thin and often curved
‣ important for protecting delicate viscera
Sesamoid
-appendicular skeleton
‣ partially or embedded in tendon
‣ protect tendon from injury (reduces friction)
‣ many sesamoids exist
Irregular
- axial skeleton
‣ shape hard to define
‣ often protect delicate viscera and provide support
