Introduction to A&P

Question 1

name the 9 regions on the surface anatomy of the abdomen

Answer 1

1. right hypochondrium
2. epigastrium
3. left hypochondrium
4. left lumbar region
5. umbilical region
6. left lumbar region
7. right iliac region
8. hypogastrium
9. left iliac region

Question 2

state the organs beneath each of the 9 regions of the surface anatomy of the abdomen

Answer 2

1. right hypochondrium -> liver, gallbladder
2. epigastrium -> stomach, liver
3. left hypochondrium -> spleen, stomach
4. right lumbar region -> right kidney, intestine
5. umbilical region -> intestinal region
6. left lumbar region -> left kidney, intestine
7. right iliac region -> appendix, intestines, ovaries
8. hypogastrium -> urinary bladder, uterus
9. left iliac region -> intestines, ovaries

Question 3

how are anatomical positions characterised by?

Answer 3

1. face looking forward
2. arms by sides with palms forward
3. feet together with toes forward

Question 4

what is the name of the anatomical position faced up?

Answer 4

supine

Question 5

what is the name of the anatomical position faced down?

Answer 5

prone
remember: ‘prone’ sounds like ‘bone’, showing the back bone to the doctor

Question 6

what is the name of the front surface of the body called in directional terms?

Answer 6

Anterior
remember: ‘A’ sounds like AH = mouth = front

Question 7

what is the name of the back surface of the body called in directional terms?

Answer 7

Dorsal/ Posterior
remember: P for 屁股 = back

Question 8

what is the name of the direction towards the head?

Answer 8

superior/ cranial

Question 9

what is the name of the direction towards the tail (coccyx of the spine)?

Answer 9

inferior/ caudal

Question 10

what is the name of the direction closer to the midline of the body?

Answer 10

medial

Question 11

what is the name of the direction further away from the midline of the body?

Answer 11

lateral

Question 12

what is the meaning of proximal?

Answer 12

is nearer to the body as compared to.
e.x shoulder is proximal to elbow

Question 13

what is the meaning of distal?

Answer 13

is further to the body as compared to.
ex. elbow is distal to the shoulder.

Question 14

what is the directional terms for near to the surface?

Answer 14

superficial

Question 15

what is the directional term for further from the surface?

Answer 15

deep

Question 16

what are the 3 body planes?

Answer 16

1. sagittal
2. transverse
3. coronal/ frontal

Question 17

explain the sagittal plane

Answer 17

divides the body into left and right
remember: S for left and right

Question 18

explain the transverse plane

Answer 18

divides the body into superior and inferior
remember: T for up and down

Question 19

explain the coronal/ frontal plane

Answer 19

divides the body into anterior and posterior (front and back)

Question 20

what does the failure of homeostasis lead to?

Answer 20

• improper function of cells
• destruction of cells
• cell death -> tissue death -> organ dysfunction -> illness, death

Question 21

what are some variables maintained by homeostasis?

Answer 21

1. body temperature: 36.5°C - 37.5°C
2. blood pressure: 90/60 - 130/85
3. plasma glucose level: 70-110 mg/dl
4. blood pH: 7.35-7.45

Question 22

how is the regulation mechanism maintained by?

Answer 22

a loop called feedback; made up of the receptor, control centre and the effector

Question 23

what do the receptors do?

Answer 23

-detects changes in the variable, convey the changes to the control centre.
ex. skin receptors sense the changes in cold/hot/ pressure and convey the information to the central nervous system.

Question 24

what does the control centre do?

Answer 24

• receives information from the receptor, determines the set point (range) at which a variable is to be maintained, send information to the effctor
  ex. temperature regulatory centre acts like a thermometer

Question 25

what does the effector do?

Answer 25

• a cell or organ that responds to the commands of the control centre, aims to restore the homeostasis by either encouraging or discouraging the stimulus.

Question 26

what is the negative feedback?

Answer 26

Negative feedback mechanism where the variable/ stimulus is discouraged, resulting in the reduction or cessation of this process.
ex. regulation of temperature, blood pressure, glucose.
How it works (temperature) : when body temperature exceeds 37℃ -> sensors like nerve cells with endings in the skin and brain -> temperature regulatory centre in the brain -> sweat glands throughout body bring down body temperature.
(glucose): after meals, food is digested to glucose and absorbed glucose enters blood. -> increased glucose level stimulates the production of hormone insulin which pushes glucose into the cells. -> thus brings down the level of glucose achieving homeostasis.
Reversely, when starving, the glucose level in the blood reduces. -> reduced glucose level stimulates the production of glucagon which converts the storage glucose (glycogen) to glucose. -> thus brings up the glucose level, achieving homeostasis.

Question 27

what is the positive feedback?

Answer 27

Positive feedback mechanism when the mechanism is encouraged, the process is increased.
ex. childbirth, blood clotting, breastfeeding
How this works (childbirth): Hormone oxytocin produced by the brain stimulates the
contraction of the uterus. -> This muscle contraction produces pain sensed by the nervous system. -> Instead of lowering the oxytocin and the pain, more oxytocin is produced until the contractions are powerful enough to produce childbirth.