Human Biology

Three types of muscular tissue

Smooth (GI), cardiac (cardiovascular system), skeletal (musculoskeletal)

Contractility

Ability to contract (shorten)

Excitability

Responsive in presence of stimuli

Conductivity

Rapid transmission of stimuli

Distensibility

Ability to stretch

Elasticity

Ability to return to original length

Sarcomere

The functional unit of skeletal muscle

Myosin

Thick filament

Actin

Thin filament

Motor unit

Nerve and muscle fiber team up

Glycolytic energy (anaerobic)

Stored ATP

Oxidative energy (aerobic)

Requires oxygen

Isometric muscle contraction

Contraction without movement

Concentric muscle contraction

Contraction with muscle shortening

Eccentric muscle contraction

Contraction with muscle lengthening, 40% greater strength

Endurance training

Increased blood supply, increased mitochondria

Resistance training

Decreased blood supply, increase of myofibrils

Muscle disuse

Decreased myofibrils

Pec major

Example of convergent muscle

Orbicularis oculi (surrounding the eye)

Example of circular muscle

Shrugs shoulders

Upper trap

Lateral raises shoulder

Deltoid

Flexes elbow

Bicep

Extends elbow

Tricep

Major posture players

Rhomboids and multifidus

Extend hip

Glutes

Extend the knee

Quads

Flex the knee

Hamstrings

Point the toes (plantar flexion)

Gastroc/Soleus

Pulls up toes (dorsiflexion)

Tibalis anterior

Neuron

The functional unit of the nervous system

Neuroglia

Helper cells for neurons (nutrients, waste removal, capable of mitosis)

Cardiac and smooth muscles

Where are electrical synapses found?

The majority of the body

Where are chemical synapses found?

Excitatory postsynaptic potentials

Depolarization

Inhabitory postsynaptic potentials

Hyperpolarization; ex: dopamine prevents involuntary movements

White matter

Axons with myelin sheaths

Gray matter

Neural cell bodies/axon terminals/dendrites, located on outer part of brain

Frontal lobe

Executive function, personality, thought, emotion, judgment, self-control, somatic muscle, learning; idea of “consciousness”; primary motor cortex and Broca’s area

Parietal lobe

Sensory info (touch) and sensory integration, proprioception (knowing where your body is in space), context perception (kitchen items); primary somatosensory cortex and Wernicke’s area

Function of Broca’s area

Speech production

Function of Wernicke’s Area

Speech comprehension

Temporal lobe

Object/facial recognition, memory storage, language and understanding, emotional reaction/processes; Wernicke’s Area, amygdala, hippocampus, fusiform gyrus (link to occ. lobe), auditory cortex

Occipital lobe

Spatial and color processing; primary visual cortex

Reflex arc

Triggered by temperature, pressure, stretch, or pain

Stretch reflex arc

A knee jerk or body twitch

Withdraw reflex arc

Happens when you touch something hot

Overload reflex arc

Happens when your arm gives out, like when you’re lifting a weight that’s too heavy

Osteoblast (builds), osteoclast (tears down), osteocyte (mature cell)

Three types of bone

Protection, mineral storage (calcium), blood cell formation (red bone marrow), fat storage (yellow bone marrow), movement, and support

Functions of the skeletal system

Long, short, flat, irregular, sesamoid

Types of bones by shape classification

As a kid

When do you have more red bone marrow?

When you’re older

When do you have more yellow bone marrow?

Longitudinal bone growth

Starts at epiphyseal lines; cells keep multiplying and pushing the cells toward the center of the bone; long bones only

Appositional bone growth

Bones increase in diamenter (they get thicker); happens with all bones

Comminuted fracture

Type of fracture where bone is shattered into multiple fragments; occurs in car accidents

Avulsion fracture

Type of fracture caused by muscle contraction; often occurs in young athletes

Epiphyseal fracture

Fracture of the epiphyseal/growth plate, sports are a common cause

Stress fracture

Fracture caused by sudden or prolonged demand; most frequently occur in women

Humerus and scapula

Bones in shoulder joint

Humerus, ulna, radius

Bones in elbow joint

Ilium, ischium, pubis, femur

Bones in hip joint

Femur, tibia

Bones in knee joint

Question, research, hypothesis, experiment, analyze/draw conclusion, support/refute hypothesis

Steps of scientific method

Natural and staged

Types of observations

Spontaneous forming of life, self “taught” reproduction, beneficial mutations, “new” information

Requirements of evolution

Lactase tolerance, malaria resistance (sickle cell anemia)

Examples of beneficial mutations (beneficial in certain contexts - dependent on environment)

Beneficial in certain contexts, unlikely though that mutations could lead to the origin of new, beneficial traits; most mutations are harmful or neutral (albinism, hemophilia, cancer)

Are mutations good? Bad?

Homologous structures

Features of different organisms that are similar due to a common ancestor; genetic code, development path

Vestigial structure

A body feature that has supposedly been inherited from an ancestor but now serves no function (tonsils, appendix)

Stonehenge, Machu Picchu, Mayan Observatory, Nazca Lines

Examples of intelligently created beings

Cellular composition, metabolism, growth, excretion, responsiveness, movement, reproduction

Characteristics of living organisms

Chemical, cellular, tissue, organ, organ system, organism

Levels of structural organization

Require a set “point”, stimulus, receptor, control center, effector/response

Explain feedback loops

Negative feedback loop

Effector counters initial stimuli (body temperature, blood sugar, blood pressure, hormone regulation, blood pH, C02 concentration)

Positive feedback loop

Effector encourages initial stimuli (childbirth, blood clotting)

Homeostasis

The body’s ability to obtain and maintain a relatively stable internal environment