Physiology Week 1

define human physiology

the study of the human body & its parts function

describe the molecular level of organization.

consists of all molecules, which are groups of atoms bound together

how does the molecular level relate to the other levels of organization?

many different molecules come together to form a cell & its parts

describe the cellular level of organization.

consists of cells, the basic unit of life

how does the cellular level relate to the other levels of organization?

cells come together to form tissues

describe the tissue level of organization.

consists of groups of similar cells that come together to perform specific functions

how does the tissue level relate to the other levels of organization?

the four types of tisue come together to form organs/different parts of the body

describe the organ system level.

consists of 2 or more tissues that come together to perform specific functions

how does the organ system level relate to the other levels of organization?

organ systems keep us alive and form many key body components

what is homeostasis?

mainteince of a relatively stable internal environment

what is an example of homeostasis?

regulation of body temperature

what is integration?

when different cells, tissue, or organs come together to form a specific function

what is an example of integration?

central nervous system, cardiovascular system, kidneys & adrenal glands all come together to regulate blood pressure

what is communication?

process of talking to different parts of the body in order to execute a certain function

what is an example of communication?

cardiac muscle cells are able to transmit electrical signals with one another through the presence of gap junctions

what is a mechanism of action?

how a physiological process occurs

what is an example of a mechanism of action?

pancreas regulates blood glucose through relase of insulin, which binds to target tissues to decrease plasma glucose levels

what is a structure-function relationship?

how a body part is organized and its designated function are closely related

what is an example of a structure-function relationship?

more dendrites a neuron has, the greater the amount of input signals a neuron can recieve

where is the intracellular fluid located?

B

where is the extracellular fluid located?

C

where is the plasma located?

A

which fluid components make up the internal environment?

interstitial fluid & plasma

identify whether glucose found within the plasma is part of the cell’s external or internal environment. explain how you came to your conclusion.

internal environment because plasma is part of a cell’s internal environment

identify whether glucose found w/in the urine in the bladder is part of the cell’s external/internal environment. explain how you came to your conclusion.

external environment because the urinary system moves fluids outside of the body

Below is an example of the reflex arc known as the swallowing reflex.
1. After swallowing a bite of food, the food stretches the soft pallet which is in the back of the
mouth.
2. These physical changes caused by food hitting the soft pallet triggers mechanoreceptors
(receptors sensitive to changes in length).
3. Afferent sensory neurons send signals to the central brain.
4. The brain sends a message to skeletal muscle present in the esophagus through efferent nerves
which causes the soft pallet to elevate, the glottis to close and the opening of the upper
esophageal sphincter.
5. Food can move deeper in the esophagus/into the stomach and the back of the mouth is cleared.
The soft pallet, glottis and upper esophageal sphincter return to their original positions. Identify the stimulus in this reflex arc.

food stretching soft pallet

Below is an example of the reflex arc known as the swallowing reflex.
1. After swallowing a bite of food, the food stretches the soft pallet which is in the back of the
mouth.
2. These physical changes caused by food hitting the soft pallet triggers mechanoreceptors
(receptors sensitive to changes in length).
3. Afferent sensory neurons send signals to the central brain.
4. The brain sends a message to skeletal muscle present in the esophagus through efferent nerves which causes the soft pallet to elevate, the glottis to close and the opening of the upper esophageal sphincter.
5. Food can move deeper in the esophagus/into the stomach and the back of the mouth is cleared.
The soft pallet, glottis and upper esophageal sphincter return to their original positions. Identify the receptor in this reflex arc.

mechanoreceptors

Below is an example of the reflex arc known as the swallowing reflex.
1. After swallowing a bite of food, the food stretches the soft pallet which is in the back of the
mouth.
2. These physical changes caused by food hitting the soft pallet triggers mechanoreceptors
(receptors sensitive to changes in length).
3. Afferent sensory neurons send signals to the central brain.
4. The brain sends a message to skeletal muscle present in the esophagus through efferent nerves which causes the soft pallet to elevate, the glottis to close and the opening of the upper esophageal sphincter.
5. Food can move deeper in the esophagus/into the stomach and the back of the mouth is cleared.
The soft pallet, glottis and upper esophageal sphincter return to their original positions. Identify the afferent pathway in this reflex arc.

afferent sensory neurons

Below is an example of the reflex arc known as the swallowing reflex.
1. After swallowing a bite of food, the food stretches the soft pallet which is in the back of the
mouth.
2. These physical changes caused by food hitting the soft pallet triggers mechanoreceptors
(receptors sensitive to changes in length).
3. Afferent sensory neurons send signals to the central brain.
4. The brain sends a message to skeletal muscle present in the esophagus through efferent nerves which causes the soft pallet to elevate, the glottis to close and the opening of the upperesophageal sphincter.
5. Food can move deeper in the esophagus/into the stomach and the back of the mouth is cleared.
The soft pallet, glottis and upper esophageal sphincter return to their original positions. Identify the integrating center in this reflex arc.

brain

Below is an example of the reflex arc known as the swallowing reflex.
1. After swallowing a bite of food, the food stretches the soft pallet which is in the back of the
mouth.
2. These physical changes caused by food hitting the soft pallet triggers mechanoreceptors
(receptors sensitive to changes in length).
3. Afferent sensory neurons send signals to the central brain.
4. The brain sends a message to skeletal muscle present in the esophagus through efferent nerves which causes the soft pallet to elevate, the glottis to close and the opening of the upper esophageal sphincter.
5. Food can move deeper in the esophagus/into the stomach and the back of the mouth is cleared.
The soft pallet, glottis and upper esophageal sphincter return to their original positions. Identify the efferent pathway in this reflex arc.

efferent motor neurnos

Below is an example of the reflex arc known as the swallowing reflex.
1. After swallowing a bite of food, the food stretches the soft pallet which is in the back of the
mouth.
2. These physical changes caused by food hitting the soft pallet triggers mechanoreceptors
(receptors sensitive to changes in length).
3. Afferent sensory neurons send signals to the central brain.
4. The brain sends a message to skeletal muscle present in the esophagus through efferent nerves
which causes the soft pallet to elevate, the glottis to close and the opening of the upper
esophageal sphincter.
5. Food can move deeper in the esophagus/into the stomach and the back of the mouth is cleared.
The soft pallet, glottis and upper esophageal sphincter return to their original positions. Identify the effector in this reflex arc.

soft pallet, glottis, upper esophageal sphincter

Below is an example of the reflex arc known as the swallowing reflex.
1. After swallowing a bite of food, the food stretches the soft pallet which is in the back of the
mouth.
2. These physical changes caused by food hitting the soft pallet triggers mechanoreceptors
(receptors sensitive to changes in length).
3. Afferent sensory neurons send signals to the central brain.
4. The brain sends a message to skeletal muscle present in the esophagus through efferent nerves
which causes the soft pallet to elevate, the glottis to close and the opening of the upper
esophageal sphincter.
5. Food can move deeper in the esophagus/into the stomach and the back of the mouth is cleared.
The soft pallet, glottis and upper esophageal sphincter return to their original positions. Identify the response in this reflex arc.

food is moved further down esophagus & into stomach until mouth is cleared, decreasing degree of stretch of soft pallet

what kind of feedback is being described by the swallowing reflex? why?

negative feedback because the response opposes the stimulus

consider the following scenario: you are heading to the gym for your regular workout. before even beginning to exercise, you notice that your heart rate increases. identify whether these situations are examples of positive feedback, negative feeback, or a feedforward mechanism and explain why.

feedforward mechanism because the body is undergoing a change in anticipation of an event

consider the following scenario: you are waiting for the bus on a cold, winter day. you notice you begin to shiver & feel yourself getting a little bit warmer identify wheser this situations are positive or negative feedbark, or a feedforward mechanism and explain why.

negative feedback because the response opposes the stimulus

consider the following scenario: a newborn begins nursing; milk production continues until the newborn stops nursing. identify whether this situation is an example of positive or negative feedback, or a feedback mechanism and why

positive feedback because the stimulus reinforces the response

is the brain in the central or peripheral nervous system?

central

are the cranial nerves in the central or peripheral nervous system?

peripheral

are the peripheral nerves part of the central or peripheral nervous system?

peripheral

is the spinal cord part of the central or peripheral nervous system?

central

what is the function of the central nervous system?

recieving input signals, interpreting input info and sending output signals to the rest of the body

what is the major function of the peripheral nervous system?

convey sensory info to the CNS and output info from the CNS

what are the 2 major branches of the peripheral nervous system?

efferent & afferent division

what are the 3 branches of the autonomic nervous system?

sympathetic, parasympathetic and enteric nervous system

identify the nucleus in the picture.

C

identify the cell body in the picture.

D

identify the dendrites in the picture.

A

identify the axon in the picture.

B

identify the axon terminal in the picture.

E

what is the major function of the cerebrum?

regulating voluntary actions, conscious activity & processing/reception of sensory info

what is the major function of the brainstem?

control centers for respiration & heart rate & is a major regulator of subconscious activity & reflexes

what is the major function of the cerebellum?

controlling movement, posture, balance & motor learning

What is the major function of the hypothalamus?

major regulator of homeostasis

what is the major function of the thalamus?

final relay center of sensory info & plays critical role in sensory perception

what kind of information is conveyed through the afferent division of the peripheral nervous system?

sensory info

what kind of information is conveyed through the efferent division of the peripheral nervous system?

motor info

what are the 3 major types of senses?

somatic, visceral, & special senses

describe somatic senses.

senses that we are consciously aware of

describe visceral senses.

senses that we are not consciously aware of

describe special senses.

senses that are difficult to categorize as “visceral” or “somatic” (balance, hearing, vision)

what are the 2 major types of motor output?

somatic & visceral

describe somatic output.

leads to actions that we have conscious control of

describe visceral output.

leads to actions we have no conscious control over.

is a sensory neuron unipolar or multipolar?

unipolar

is a motor neuron unipolar or multipolar?

multipolar

is an interneuron unipolar or multipolar?

multipolar

identify gray matter in the picture.

I

identify white matter in the picture.

E

identify the dorsal root in the picture.

G

identify the ventral root in the picture.

C

identify the dorsal horn in the picture.

F

identify the dorsal root ganglion.

H

identify the anterior side in the picture.

B

identify the posterior side in the picture.

A

what is grey matter made of?

cell bodies of neurons and synapses

what is the general function of grey matter?

process info/integrate info

what is white matter made of?

myelinated axons of neurons

what is the general function of white mater?

transmit signals between neurons

what is the difference between a neuron and a nerve?

a nerve is a single cell while a nerve is the collection of muelinated axons in the peripheral nervous system

what are ganglia?

collection of cell bodies and synapses

where are ganglia found?

peripheral nervous system

what type of information is conveyed through ascending tracts?

sensory info

what type of information is conveyed through descending tracts?

motor info

how many pairs of cranial nerves are there?

8

which parts of the body do the cranial nerves innervate?

head, neck, shoulders, arms, hands

how many pairs of thoracic nerves are there?

12

which part of the body do the thoracic nerves innervate?

chest, upper abdomen

how many pairs of lumbar nerves are there?

5

which parts of the body do the lumbar nerves innervate?

lower abdomen, hips, legs

how many pairs of sacral nerves are there?

5

what parts of the body do the sacral nerves innervate?

genitals, lower digestive tract

how many coccygeal nerves are there?

1

which parts of the body do the coccygeal nerves innervate?

skin laying above tailbone

given the small size of the ventral horns in the thoracic spinal cord, what might this tell us about the function of the thoracic spinal cord?

there is not a lot of motor output to thorax/upper abdomen

identify a in the picture.

cell body

identify b in the picture

axon

identify c in the picture.

sensory receptor

identify d in the picture.

peripheral nervous system

identify e in the picture.

trigger zone

identify f in the picture.

central nervous system