Chapter One Part TwoChapter One Part TwoReview of HomeostasisReview of HomeostasisLevels of OrganizationLevels of OrganizationOrganization of the Human bodyOrganization of the Human bodyAnatomical TerminologyAnatomical Terminology

Homeostasis QuestionsHomeostasis Questions

There is a homeostasis question at There is a homeostasis question at each table. each table.

Answer the question within your group. Answer the question within your group.

Choose a member of your group to Choose a member of your group to report out the answer to the class. report out the answer to the class.

You have 5-7mins to complete your You have 5-7mins to complete your questions. questions.

Homeostatic Mechanism

Complete the diagram!

Homeostasis ReviewHomeostasis Review

http://www.teachersdomain.org/resource/tdc02.sci.life.reg.bodycontrol/

Body Control Center QuestionsBody Control Center Questions

What is homeostasis?What is homeostasis? Body’s attempt to maintain a stable

internal environment

What controls human heart rate? Under What controls human heart rate? Under what conditions does heart rate change?what conditions does heart rate change?

Pacemaker, receptors in circ. Pacemaker, receptors in circ. system, brainsystem, brain

Increase or decrease in oxygen Increase or decrease in oxygen and carbon dioxide levels due and carbon dioxide levels due to things like exercise or sleep to things like exercise or sleep and certain chemicals can and certain chemicals can cause change. cause change.

How is respiration rate controlled?How is respiration rate controlled? Rate based on levels of Rate based on levels of

carbon dioxide and carbon dioxide and oxygen. Brain can cause oxygen. Brain can cause increase or decrease in increase or decrease in rate. Can be consciously rate. Can be consciously controlledcontrolled

Could you hold your breath indefinitely? What Could you hold your breath indefinitely? What would happen?would happen?

No, when carbon dioxide builds up you lose voluntary control of respiratory muscles. The body is forced to exhale.

In what different ways does the body control In what different ways does the body control

temperature?temperature? Heat can be exhaled. Blood Heat can be exhaled. Blood

also carries blood to skin also carries blood to skin surface. Perspiration surface. Perspiration carries the most heat carries the most heat away when the water in away when the water in sweat evaporates.sweat evaporates.

How does the bodyHow does the body maintain a steady level of sugar in the maintain a steady level of sugar in the

bloodstream? What happens if it is unable to regulate blood bloodstream? What happens if it is unable to regulate blood sugar?sugar?

Two hormones control Two hormones control blood sugar- insulin blood sugar- insulin decreases levels and decreases levels and glucagon increases glucagon increases levels.levels.

DiabetesDiabetes

What factors control What factors control blood pressure?blood pressure?

The amount of blood your heart pumps—how fast it The amount of blood your heart pumps—how fast it pumps and how forceful each contraction is—is a pumps and how forceful each contraction is—is a major factor in determining blood pressure. There major factor in determining blood pressure. There are other factors, too. The amount of blood in the are other factors, too. The amount of blood in the body affects pressure, for example (less blood body affects pressure, for example (less blood results in lower pressure). Also, the brain can alter results in lower pressure). Also, the brain can alter the diameter of the vessels, dilating (widening) them the diameter of the vessels, dilating (widening) them to reduce pressure and constricting (narrowing) to reduce pressure and constricting (narrowing) them to increase pressure. The brain responds to them to increase pressure. The brain responds to signals it receives from various cells throughout the signals it receives from various cells throughout the body; some of these are sensitive to levels of body; some of these are sensitive to levels of oxygen and carbon dioxide, some to chemicals, and oxygen and carbon dioxide, some to chemicals, and some to blood pressure itself.some to blood pressure itself.

How is this How is this Body Control Center Flash Interactive simulation like the self-regulation that goes on in an actual human body? How

is it different? The body must constantly make changes to The body must constantly make changes to

maintain stability (homeostasis) just like in maintain stability (homeostasis) just like in activity. Even when stability is reached the activity. Even when stability is reached the organism can change activities and cause organism can change activities and cause new changes necessary to maintain new changes necessary to maintain stability.stability.

In the body many more things are must be In the body many more things are must be regulated. Some of these things can affect regulated. Some of these things can affect other things so multiple changes are other things so multiple changes are actually necessary.actually necessary.

If various physiological responses are constantly If various physiological responses are constantly adjusting, do you think the body is ever in adjusting, do you think the body is ever in

equilibrium? Why or why not?equilibrium? Why or why not?

The body generally is The body generally is always striving for always striving for equilibrium but never equilibrium but never quite reach it because quite reach it because conditions are constantly conditions are constantly changing.changing.

Levels of Organization in the body:Levels of Organization in the body:

AtomAtom MoleculeMolecule MacromoleculeMacromolecule OrganellesOrganelles CellsCells TissueTissue OrgansOrgans Organ SystemsOrgan Systems OrganismOrganism

Anatomical Planes of the Anatomical Planes of the Human BodyHuman Body

Anatomical Planes DefinedAnatomical Planes Definedp.14 Fig. 1.11p.14 Fig. 1.11

Saggital (median) Plane – lengthwise cut of Saggital (median) Plane – lengthwise cut of the body into right and left sides; if passes the body into right and left sides; if passes along midline, then body is in equal parts = along midline, then body is in equal parts = medianmedian

Transverse (horizontal) plane – cut that Transverse (horizontal) plane – cut that divides body into superior and inferior divides body into superior and inferior portionsportions

Coronal (frontal) plane – divides body into Coronal (frontal) plane – divides body into anterior and posterior views. anterior and posterior views.

Anterior and Anterior and Posterior Posterior

viewview

Anterior and Posterior PositionsAnterior and Posterior Positions

Anterior – Anterior – means towards the frontmeans towards the front

Posterior – Posterior – opposite view of anterior; opposite view of anterior;

means toward the backmeans toward the back

Superior Superior and Inferior and Inferior

ViewsViews

Superior and Inferior ViewsSuperior and Inferior Views

Superior – Superior – means the body part is above means the body part is above

another part or is closer to the another part or is closer to the head. head.

Inferior – Inferior – means the body part is below means the body part is below

another part or is closer to the another part or is closer to the feet feet

Medial Medial and and

Lateral Lateral ViewsViews

Medial and Lateral Medial and Lateral Medial - Medial -

relates to an imaginary midline dividing relates to an imaginary midline dividing the body into equal left and right halves. the body into equal left and right halves. Body part is medial if it is close to the Body part is medial if it is close to the midline. (Nose is medial to the eyes)midline. (Nose is medial to the eyes)

Lateral – Lateral – means toward the side with respect to means toward the side with respect to

the imaginary midline (Ears are lateral to the imaginary midline (Ears are lateral to the eyes)the eyes)

Proximal Proximal and Distal and Distal

ViewsViews

Proximal and Distal Proximal and Distal Proximal – Proximal –

describes a body part that is closer to a describes a body part that is closer to a point of attachment than another body point of attachment than another body part. (Elbow is proximal to the wrist)part. (Elbow is proximal to the wrist)

Distal – Distal – opposite of proximal; particular body opposite of proximal; particular body

part is farther from a point of attachment part is farther from a point of attachment than another body part. (Fingers are than another body part. (Fingers are distal to the wrist)distal to the wrist)

Superficial and DeepSuperficial and Deep

Superficial – Superficial – situated near the surfacesituated near the surface

Deep – Deep – parts that are more internalparts that are more internal

Body ViewsBody Views

Axial Portion – head, neck, trunkAxial Portion – head, neck, trunkDorsal cavity – cranial cavity and Dorsal cavity – cranial cavity and

vertebral canalvertebral canal Ventral Cavity – Thoracic cavity, Ventral Cavity – Thoracic cavity,

Diaphragm, abdominopelvic cavityDiaphragm, abdominopelvic cavity

Appendicular Portion – Appendicular Portion – arms & legsarms & legs

Body Body CavitiesCavitiesLateral Lateral ViewView

Body Body Cavities Cavities Coronal Coronal

ViewView

Cranial

Spinal/ Vertebral

Mediastinum

Pleural

Pericardial

Diaphragm

Abdominal

PelvicAbdominopelvic

Ventral

Body CavitiesBody Cavities

cranial cavitiy – cranial cavitiy – houses the brainhouses the brain

vertebral canal –vertebral canal – spinal cord and some vertebraespinal cord and some vertebrae

Body CavitiesBody Cavities

Thoracic cavity – Lungs and moreThoracic cavity – Lungs and more Mediastinum region (separates right and Mediastinum region (separates right and

left lungs) = heart, esophagus, trachea, left lungs) = heart, esophagus, trachea, and thymusand thymus

Diaphragm – Diaphragm – separates the thoracic from the separates the thoracic from the

abdominopelvic abdominopelvic

Body CavitiesBody Cavities

abdominopelvic cavity – abdominopelvic cavity – Abdominal cavity – stomach, liver, Abdominal cavity – stomach, liver,

spleen, gallbladder, kidneys, most of the spleen, gallbladder, kidneys, most of the small and large intestinessmall and large intestines

Pelvic cavity – enclosed by hip bones; Pelvic cavity – enclosed by hip bones; includes terminal portion of large includes terminal portion of large intestine, urinary bladder, and internal intestine, urinary bladder, and internal reproductive organs. reproductive organs.

Head Head CavitiesCavities

Head CavitiesHead Cavities

Oral cavity – teeth and tongueOral cavity – teeth and tongue Nasal cavity – within the nose; divided into Nasal cavity – within the nose; divided into

right and left regions by nasal septumright and left regions by nasal septum Sinuses – frontal and sphenoidal sinuses Sinuses – frontal and sphenoidal sinuses

connect to nasal cavityconnect to nasal cavity

Orbital cavity – eyes, skeletal muscles, Orbital cavity – eyes, skeletal muscles, and nervesand nerves

Middle Ear Cavity – middle ear bonesMiddle Ear Cavity – middle ear bones

There will be a Quiz on There will be a Quiz on Body Views, Cavities, and Body Views, Cavities, and

RegionsRegions

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