The Human Body Plan

Question 1

Structural Levels of the Human Body

Answer 1

Atoms -> Molecules -> Cells -> Tissues -> Organs -> Systems -> Organism

Question 2

Cell

Tissue - 4 types

Organ

Answer 2

Cell: Basic unit of structure (Structure varies)
Tissues: Precise organisations of similar cells that perform specialised functions. 4 types;
-i) Epithelial: covers exposed surfaces & lines body cavities
-ii) Connective: Protects, supports & interconnects body parts/organs
-iii) muscle: produces movement
-iv) nervous: conducts impulses for internal communication
Organ: 2+ tissue types combined (e.g. small intestine, brain)

Question 3

Organ System

Organism

Answer 3

Organ System: Related organs that work together to co-ordinate activities and achieve a common function
Organism: Highest level - all body systems working together

Question 4

7 Characteristics of Living Things

Answer 4

1. Organisation
2. Metabolism - various chemical reactions (e.g. contracting muscles, breaking down nutrients)
3. Growth & Development - Increase size in life (growth) & increasing specialisation related to form and function (Development)
4. Responsiveness - Ability to sense
5. Adaptation - Over time may alter structure, physiology or behaviour to increase survival
6. Regulation - (aka homeostasis)
7. Reproduction - new cells for growth/repair & sex cells

Question 5

Name the 11 Organ Systems

Answer 5

“Run Mrs. Lidec”

• Respiratory
• Urinary
• Nervous
• Muscular
• Reproductive
• Skeletal
• Lymphatic
• Integumentary
• Digestive
• Endocrine
• Cardiovascular

Question 6

Overview on what the organ systems do:

• Respiratory
• Urinary
• Nervous
• Muscular

Answer 6

• Respiratory: Exchanges gases (O & CO2) between blood & air in lungs
• Urinary: Filters Blood & removes waste products from blood - concentrates them into urine (& expels it)
• Nervous: Regulatory system that controls body movement, responds to sensory stimuli & helps control all other systems
  
  • also responsible for consciousness, memory & intelligence
• Muscular: Produces body movement & generates heat (thru. contraction)

Question 7

Overview on what the organ systems do:

• Reproductive
• Skeletal
• Lymphatic
• Integumentary

Answer 7

• Reproductive: Produces sex cells and relevant hormones
• Skeletal: Provides support & protection; site of homeopoiesis (blood cell production), stores Ca & P; provides site for muscular attachment.
• Lymphatic: Transports & Filters lymph (interstitial fluid transported thru lymph vessels) & initiates immune response when necessary.
• Integumentary: Protection; regulates body temp.; site of cutaneous receptors; syn. vitamin D & prevents water loss

Question 8

Overview on what the organ systems do:

• Digestive
• Endocrine
• Cardiovascular

Answer 8

• Digestive: Mechanically & chemically digests food, absorbs nutrients & expels waste products
• Endocrine: Consists of glands & cell clusters that excrete hormones (e.g. ones that regulate body & cellular growth, chem. levels & reproductive function)
• Cardiovascular: Consists of heart, blood & blood vessels. Heart moves blood through vessels to distribute hormones, nutrients & gases, & to pick up wastes

Question 9

The Anatomical Position

Answer 9

Characteristics;

• Standing upright
• Feet parallel and on floor
• Head level & looking forward
• Arms by side of body
• Palms facing forward & thumbs pointing away from body

Question 10

Section & Planes

Answer 10

Section: An actual cut or slice through structure, or a piece removed by slicing a structure
Plane: Imaginary flat surfaces passing through the body or an organ
-3 Major Planes;
1. Coronal (frontal) Plane: Vertical plane that divides the body into anterior (Front) and posterior (back) parts
2. Transverse (Horizontal) Plane: Cuts perpendicularly along the long axis of the body or organ. The body is separated into both superior (upper) and inferior (lower) parts.
3. Midsaggital (Median) Plane: Extents through body or organ vertically, dividing the structure into equal left and right parts.
-sagittal = parallel to midsaggital (though not in equal left and right parts)

-Are also Oblique Planes (those that pass thru specimen at an angle

Question 11

Divisions of Regional Anatomy

Answer 11

1. Axial: head, neck, and trunk (vertical axis of body)

2. Appendicular: upper and lower limbs (appendages)

Question 12

Body Cavities - Posterior & Ventral cavities

Answer 12

Posterior Cavities:
-Cranial: Formed by skull bones
-Vertebral: formed by vertebral column bones
Ventral Cavities:
-Thoracic: the superior cavity (Ribcage)
-Abdominopelvic: the inferior cavity (physically separated by diaphragm

Question 13

Cavity Membranes

Answer 13

• Ventral cavities lined by a very thin serous membrane
• divided into 2 continous parts:
  
  1. Parietal layer: Lines the internal surface of the body wall
     2. Visceral layer: Covers the external surface of the organs in the cavity

-Both layers produce small amount of fluid (serous) to lubricate the organs to protect from friction

Question 14

Define -;

Caudal
Cranial
Rostral
Ipsilateral
Contralateral
Deep
Superficial
Proximal
Distal

Answer 14

Caudal - at rear or tail end
Cranial - at head end
Rostral - towards nose
Ipsilateral - on same side
Contralateral - on opposite side
Deep (internal) - on the inside, underneath another structure
Superficial (external) - on the outside
Proximal - Closest to point of attachment to trunk
Distal - furthest from point of attachment to trunk