PNB Exam #1

Anatomy

study of biological STRUCTURES

Levels of the body from smallest to largest

chemical level (atoms) -> cellular level -> tissue -> organs -> organ system

Gross anatomy (with examples)

Study of structures that can be seen with the naked eye

- no microscope is needed

ex: bones, organs, muscles, blood vessels, nerves

Histology

- study of tissue

- subdicipline of anatomy

Cytology

- study of cells

- subdicipline of anatomy

Connectomics

- study of the connections between neurons

- new field

5 Anatomy Subdisciplines

- Cytology

- Histology

- Gross Anatomy

- Embryology

- Neuroanatomy

Physiology

the study of biological FUNCTION

5 Physiology Subdisciplines

- muscle physiology

- sensory physiology

- endocrinology

- receptor physiology

nuerophysiology

What happens if structure does not match function

disease

What does structure dictate

FUNCTION

Human Anatomical Position

- standing upright

- feet parallel on the floor

- head level/eyes forward

- palms facing outward

2 important factors when speaking in anatomical terminology

- need to be precise

- relative to other body parts

How do you define location in Anatomical Terms

location from perspective of subject

-ex: not our left but their left

Axial Structures

head and trunk

(skull, auditory ossicles, sternum, ribs, vertebrae, sacrum, coccyx)

Appendicular Structures

- arms and legs

(shoulder girdle, arm, hand, pelvic girdle, leg, foot)

4 quadrants of the abdomen

- left upper

- left lower

- right upper

- right lower

(in anatomical terms)

If there were issues with the left upper quadrant, what might be the cause?

Liver problems

If there were issues with the lower left quadrant, what might be the cause?

issues with the intestine

If there were issues with the lower right quadrant, what might be the cause?

appendicitis

If there were issues with the upper right quadrant, what might be the cause?

gallbladder issues

What does the word appendicular come from?

Appendages (something that is attached)

Superior

Further up on the body

Inferior

Further down on the body

Anterior

closer to the front of the body

Posterior

closer to the back of the body

Ventral

Closer to the stomach

Dorsal

Closer to the back

Medial

Closer to the midline

Lateral

Farther from the midline

Proximal

Closer to the attachment point

Distal

Farther from the attachment point

Cranial

Closer to the head

Caudal

Father from the head (towards the tail)

What can Superior and Inferior be switched with?

Superior / Cranial

Inferior / Caudal

Transverse Cut

- divides the body into superior and inferior portions

- horizontal

Sagittal Cut

- divides the body into right and left portions

- any vertical cut

- does not have to be even

Midsagittal Cut

- separating left and right equally

- vertical cut

Coronal Cut

- divides the body into anterior and posterior portions

- there is a front and back piece)

- also called a frontal cut

bilaterial symmetry

can be divided down its length into similar right and left halves

- humans have this

Homeostasis

- maintain relative constant conditions

Setpoint

any given biological parameter needed to be maintained

- narrow range

- ex: body temp

Can setpoints change? (even in the same place)

- they can fluctuate

- ex: hormones while sleeping vs wake

- hormones during puberty, pregnancy, and menopause

What can being out of homeostasis cause?

Disease

How is homeostasis contained?

Negative Feedback

What is the simple loop of negative feedback?

initial stimulus -> response -> stimulus -> initial stimulus

What does the response of the initial stimulus negate?

the new stimulus

Body Temperature Negative feedback loop

Homeostasis -> stimulus (increases body temp)-> receptors (thermoreceptors in skin) -- signal --> controller (hypothalamus detects change) -signal -> effectors (sweat glands increase secretion) -> cooling response (sweat & increase of heat loss) -> body returns to set point HOMEOSTASIS

Why is it called negative feedback?

response decreases the stimulus

For the body to react it must be a ...

negative feedback response

Positive feedback

- less common

- take you out of homeostasis

- amplify the stimulus

Simple positive feedback loop

initial stimulus -> response -> stimulus -> response - stimulus (loop until external factor stops loop

Example of positive feedback

- Labor

Labor positive feedback loop

Cervical stretch - stimulates -> oxytocin release -causes -> uterine contractions - causes -> baby to be pushed against cervix - causes -> more cervical stretch

loop until baby is born

what stops positive feedback

- external factors (something not in the loop)

Positive and Negative feedback both take place in ...

closed systems

where is the relationship in a feedback loop

between the stimulus and the response that increases or decreases that stimulus

Feedforward Response

- open system

- no relationship between stimulus and response

ex: missing the bus = increase HR and breathing but wont bring back the bus

causes of feedforward responses

- can happen for no reason

- but can be response to prepare for a situation

Different places in the body and their set points

- different places can have different set points even for the same parameter

- caused by compartmentalization

compartmentalization

keeping different parts of the body chemically or physically separate

ex: pressure environment around heart and lungs vs stomach

How is the stomach a good example of Compartmentalization?

the stomach has a ph = 2 - if other tissues had ph = 2 they would be destroyed

How are the testes a good example of compartmentalization?

The testes are compartmentalized as they are outside of the body and there is a muscle to bring them closer and father to regulate body temperature

- testes require lower body temp than the rest of the body

cells & compartmentalization

cells can be compartmentalized

- even parts in the cell are compartmentalized

2/3 of body fluid is in the ...

cytosol (intracellular fluid)

1/3 of body fluid is

extracellular fluid

(interstitial fluid, plasma, etc.)

4 major tissues

- epithelial tissues

- connective tissues

- nervous tissues

- muscle tissues

what is tissue?

collection of cells that are serving a common function inside the body

tissues give rise to ...

organs

tissues are made up of ....

different cell types

what are the differences that make tissues different? (3)

- cellular composition

- extracellular make up (matrix)

- function

what does extracellular matrix contain (4)

- proteins

- salts

- water

- other macromolecules

main functions of epithelial tissue (5)

- physical protection (water, chemical, physical injury)

- selective permeability

- secretion

- absorption

- reception

what is the outermost layer of the epithelial tissue

epidermis

what is selective permeability

allows beneficial molecules in and keeps bad molecules out

where can epithelial tissues be found

- located in places that come in contact with external environments

- lining inside the cavities of the body

is epithelial tissue always superficial?

No

- epithelial tissue can be found within the body

which tissue lines the digestive track and how is it important?

- epithelial tissue

- makes decisions of which molecules enter the body through the digestive system

how can epithelial tissue act as a receptor?

- rare : only for specialized senses

- vision: uses it to capture photons

- hearing: uses it to capture sound waves

5 general characteristics of epithelial tissue

- cellularity

- polarity

- attachment

- avascularity

- regenerative capacity

what does a high degree of cellularity mean

- ratio of cells to matrix is very high

- cells are densely packed

polarized tissue

- different membrane faces have different functions

- different channels and transporters on different sides of the membrane have different functions

why is epithelium avascular and what is it made from

- lacks blood supply

- made of dead keratinized epithelial cells

Is epithelial tissue vascular or avascular?

Avascular (no blood supply)

where does epithelial tissue get its nutrients

- connective tissue below

why is epithelial tissue avascular

- structure function relationship

- ex: if it was epithelial tissue in eye was vascular the pigment would refract the light and photons would never enter

is epithelial tissue constantly damaged

- yes

- tends to be rapidly dividing tissue to counteract damage

is epithelial tissue classified anatomically or physiologically

both

exchange epithelia

- allows rapid exchange of materials between compartments

- nonselective

- ex: lungs

transporting epithelia

- allows the rapid exchange of materials between compartments

- prevents free movement between adjacent cells

- greater selectivity

ciliated epithelia

- promotes movement of extracellular particles

- cilia on membrane faces

where is ciliated epithelia common

- respiratory system

- reproductive system

which direction does cilia move in

- cilia on adjacent cells beat in same direction which creates laminar flow

Kartagener's syndrome

- primary ciliary dyskinesia

- abnormal movement of cilia

- respiratory issues (similar to cystic fibrosis)

What do most people with Kartagener's syndrome also have?

- cistus inversus: the organs in the body are reversed

secretory epithelia

- secretes substances

- organized into glands (endocrine & exocrine)

endocrine glands

- release secretions into blood or interstitial fluid

exocrine glands

- release secretions into ducts

types of exocrine glands

- simple tubular

- simple alveolar

- compound tubular

- compound alveolar

- compound tubuloalveolar

merocrine secretion

release of a substance from a gland via exocytosis

ex: salivary glands