Exam 2- Bones (Connective Tissues Part 2), Muscles Tissues, Nervous Tissues, Circulatory System, Endocrine Systems

Front 1

What are the functions of bone?

Back 1

1) Mechanical support
2) Protection
3)Reservoir of calcium and phosphate
4) locomotion
5) hearing
6) hematopoiesis

Front 2

What are the phagocytic-function type cell in bones that is present where bone is damaged?

Back 2

osteoclasts

Front 3

what are the two precursors of osteocyte?

Back 3

osteoprogenitor cells --> osteoblast

Front 4

How is bone different from cartilage?

Back 4

1) Not flexible, its firm
2) Has vascular supplies (blood vessels)
* In cartilage, get its supplies by diffusion. In bones, due to its mineralized nature, need to have blood vessels for nutrients.

Front 5

What are the two type of bone tissues, where they are at, and what they consist of.

Back 5

1) Compact (dense): outside of bone with high level of ECM
2) Spongy (cancellous): inside of bone, meshwork of trabeculae, spaces filled with blood vessels and bone marrow.

Front 6

What are the four classifications of bones? Examples of where they can be found and describe them/

Back 6

1) Long bones: 1 longer dimension (tibia, metacarpels)
2) Short bones: length=diameter (carpal bones of hand)
3) flat bones: thin, plate-like (skull, sternum)
4) Irregular bones: verterbrae

Front 7

Where can you find the periosteum and where can you not find it?

Back 7

Periosteum = outer covering of bones except where its articulate with another bone (articular cartilage)

Front 8

Where can you find osteoprogenitor cells? Specific named for this location?
How thick is it?

Back 8

In the inner layer of periosteum. Inner layer called: endosteum.
one cell layer thick

Front 9

What is the precursor of osteoblast cells?

Back 9

osteoprogenitor

Front 10

What is the relationship and function of osteoblasts and osteocytes?

Back 10

Osteoblasts are precursor to osteocytes.
Osteoblasts secretes collagens and unminneralized matrix called Osteoids.
Became osteocytes when it has completely surrounded itself in the secreted matrix. Osteocytes are responsible for depositing and absorbing the matrix. They can synthesize/degraded bone matrix base on homeostasis

Front 11

How do osteocytes communicated with each other?

Back 11

Via canaliculi processes that forms gap junction with other osteocytes extended canalicul processes.

Front 12

Describe the mineralization process of bones.
Key terms: concentration of Ca++, PO4-, Osteocalcin, positive feedback, stimulation of osteoclasts, secretion of alkaline phosphatase,secretion of matrix vessicles and its function, crystallization of CaPO4, formation and deposition of hydroxyapatite

Back 12

in order for mineralization to occur, need high level of Ca2+ and PO4- than normal threshold level.
1) Osteocalcin binds to Ca2+ = high concentration of Ca2+
2) High Ca2+ --> osteoblasts to secrete alkaline phosphatase increasing PO4-
3) Positive feedback- the higher the level of Ca2+, the higher the level of PO4-.
4) Osteoblast then secretes matrix vesicles into bone matrix that accumulates Ca2+ and cleaves PO4-.
5) Inside the vessicle, Ca2+ and PO4- crystallized -> initiate mineralization by formation and deposition of hydroxyapatite.
6) Once hydroxyapatite is formed and released, grow rapidly= wave of mineralization.

Front 13

Are osteoclast derived from osteoprogenitor cell?

Back 13

No. It is derived from bone marrow.

Front 14

What are osteoclasts unique features?

Back 14

1- Huge
2- Multinucleated.
3- Acidophilic

Front 15

What are osteoclasts' function? Where is it founded?

Back 15

Function: breakdown matrix- eating away the bones making dents.
Found in: Howship's lacuna (site of breakdown/ bites)

Front 16

Study the bone's hormones comparison chart

Back 16

see excel: Histology chart

Front 17

What are the two type of bone ossifications? How do they differed?

Back 17

1) Intramembranous ossification:
- flat bones (ex. skulls and ribs)
- develop from mesenchymal cells
2) Endochondral ossification-
- long bones (ex. arms, legs)
- growth of cartilage templates into bones

Front 18

How does intramembraneous ossification works?

Back 18

1) mesenchymal cells condensed together, get aggregated and differentiated into osteoblasts.
2) osteoblast synthesized and secrete osteoid- which mineralized around the osteoblasts which became osteocytes

Front 19

What is appositional growth?

Back 19

process of intramembraneous ossification where the osteoblast secretes and surround itself with osteoids-> become an osteocytes. By the continual secretion of osteoids, bone growths occurred.

Front 20

Label and describe the steps shown in fig. 8.17

Back 20

Taken from lecture slide:
A) cartilage model
B) Bony collar formed
Calcified cartilage
Cavity formed
Invasion of blood vessels
Primary ossification center
cartilage spicules --> bones
C) Secondary ossification center
cartilagenous Epiphyseal plate
E) Proliferation and reabsorption in epiphyseal plate.

Front 21

What happens when there the body has low blood calcium or elevated blood calcium?

Back 21

1) In low blood calcium, PTH- parathyroid hormones increase to stimulate the osteoclasts-> which helps release Ca+ into blood.
2) In elevated blood Ca+, calcitonin increases to inhibit PTH effects on osteoclasts-which help lower blood Ca+ by prevent Ca+ release into blood.

Front 22

Which regions of the bones do Growth hormone and IGF-1 (Insulin-like growth factor) effects?

Back 22

1) GH stimulates the differentiation of osteoprogenitor cells into osteoblast- occur between the in the zone of reabsorption in between the metaphysis (??). Osteoprogenitor originated from the bone-marrow in the diaphysis.
2) IGF stimulates the proliferation of chondrocytes at the epiphyseal plate

Front 23

What happens when you have excess growth hormones- in children vs adults??

Back 23

1) In children, its call gigantism. Grow really tall due to expansion of the epiphyseal plate (growth plate).
Type of growth: can be both appositional AND endochondral
2) In adults, its called acromegaly. At this stage, growth plate has disappear already due to the convergence. Only appositional intramembraneous growth

Front 24

What is the estrogens role in bone growth?

Back 24

Pre-puberty: proliferation of growth plate
Post-puberty: closure of growth plate

Front 25

Predict what happens to individuals who either cannot make estrogens or lack estrogens receptors?

Back 25

Ephiphyseal growth plate cannot fused and therefore, the individual will keep growing

Front 26

MUSCLES

Back 26

MUSCLES TISSUE

Front 27

What are the three types of muscle tissues?

Back 27

1) Skeletal
2) Smooth
3) Cardiac

Front 28

What is the primarily function of muscles?

Back 28

Force generation

Front 29

Study the comparison chart between skeletal, cardiac, smooth

Back 29

in Excel

Front 30

*SKELETAL MUSCLES

Back 30

SKELETAL MUSCLES

Front 31

What makes skeletal muscles different from the other muscles (cardiac and smooth)?

Back 31

1) multinucleated
2) can be very long
3) regenerative capability due to presence of satellite cells in the basal lamina

Front 32

What held skeletal muscle together?
(what covers the individual muscle fibers, covering a group of individual muscle fibers (fascicle), and what covers groups of fasciles?

Back 32

CONNECTIVE TISSUES
1) Endomysium covers individual muscle fibers
2) perimysium covers groups of individual fibers
3) epimysium covers several group of fascicles

Front 33

How do muscles get their nutrient supplys from blood vessels and nerves?

Back 33

Blood vessels and nerve travels in the connective tissues to transport materials to/from muscles.

Front 34

Be sure to know the structure of muscle myofibril:
A band, I band, H band, M line, Z line/disk, sarcomere

Back 34

see notes

Front 35

A-band is a ________ filament made of (actin or myosin) in contrast to the I-band which is a ___________ filament made of (actin or myosin)

Back 35

A-band is a THICK filament made of MYOSIN.
I-band is a THIN filament made of ACTIN

Front 36

What are the components of thin actin filaments and thick myosin filaments?

Back 36

1) G-actin --> double helix F-actin
2) Tropomyosin
3) Troponin

Front 37

What are the functions of accessories proteins? Name some of them.

Back 37

Function: maintain precise alignment of thin and thick filaments.
titin, alpha-actinin, nebulin, tropomodulin, desmin, myomesin, C protein, dystrophin

Front 38

When a muscle contracts, each ________ shortens and becomes thicker, but ________ remains the same length.

Back 38

!) sacromere
2) myofilaments
* during contraction, sarcomere and I band shorten, A-band remains the same length Overlap of thin and thick filaments cause the sacromere to shorten and thicken

Front 39

What is muscle contraction dependent on the concentration of what ions?

Back 39

Ca+

Front 40

In muscle, where is the reservoir for Ca+?

Back 40

In the terminal cisterna of the sacroplasmic reticulum surrounding the myofibrils.

Front 41

What are the components of triads?

Back 41

terminal cisterna (reservoirs of Ca+) and T-tubules ( sensing the depolarization of the plasma membrane in muscles to regulate the release of Ca+)

Front 42

How are Ca+ release into muscles to start contraction?

Back 42

Nerve impulse arriving at neuromuscular junction --> plasma membrane depolarize --> Na+ channel open (influxed of Na+). This rapidly spread throughout the whole muscle causing depolariztion, sense by voltage-sensor protein on T system -->open gated Ca+ channel, release of Ca+- initiate the binding of myosin to actin by changing the conformation of tropomyosin to unblock the binding site.

Front 43

What does the intercalacted disk in the cardiac muscles show?

Back 43

junctions between cardiac muscle cells

Front 44

NERVOUS TISSUE

Back 44

NERVOUS TISSUE

Front 45

What are the functions of the nervous system?

Back 45

1) input from sensory receptors
2) integration and processing of signals
3) output to effector cells
4) Behavior

Front 46

The nervous system is divided into two parts. What are the two subdivision?

Back 46

1) Central nervous system (CNS)
2) Peripheral Nervous system (PNS)

Front 47

What are the 3 main structure of a neuron?

Back 47

Dendrites, cell body, axon

Front 48

Where are action potential generated?

Back 48

At the axon hillock- between the axon and the cell body

Front 49

What are the functions of cell body, dendrites, and axon?

Back 49

Cell body: synthesize proteins
Dendrites: received information
Axon: send information

Front 50

Where do neurons communicate with each other?

Back 50

At synaptic cleft between presynaptic neuron and postsynaptic neuron.

Front 51

What are the two types of synaptic communication?

Back 51

1) Chemical synapses: conductions of impulse achieved by release of chemical substances
2) Electrical synapses: movements of ions between cells via gap junction as way of spreading electrical current.

Front 52

What is axonal transport system? What is the purpose of it? What directions does it go in?

Back 52

Axonal transport system: is a mode of intracellular communication- used to transport synthesized material from the nerve cell body to the nerve's process (dendrites / axons).

Direction: bidirectional system

Front 53

What role does SNARE protein plays in chemical transmission?

Back 53

SNARE protein located at the axon terminal binds to presynaptic vesicle, facilitate its fusion with the presynaptic membrance for the neurotransmitter release.

Front 54

How does "Botox" (Botulinum toxin) works?

Back 54

It prevent the release of neurotransmitter by cleaving the SNARE proteins at the presynaptic axon terminal.

Front 55

What cells synthesize the myelin sheath in CNS and in PNS?

Back 55

In CNS- oligodendrocytes
In PNS- Schwann cell

Front 56

What is the advantage in having a myelin sheath?

Back 56

Those with myelineated sheath can conduct signals much faster- increase efficiency.

Front 57

What is the Node of Ranvier?

Back 57

sections of unmyelinated axons where ion channels are concentrated.

Front 58

What cause multiple Sclerosis?

Back 58

Damage to the myelin sheath which cause interrupted action potential transmission- hard to diagnose.

Front 59

What happens when there is damaged to the axon of a neuron?

Back 59

Transport is interrupted. Whole distal part died.., since target cell not stimulated, will be redistributed and reduce. Input will retracted --> muscle atrophy due to lack of stimulation.

Front 60

Compare regeneration of damaged neurons in CNS and PNS

Back 60

In PNS, regeneration is possible due to the fact the Schwann cells can divide and develope bridge connecting damaged and become healthy from there. If reconnection cannot be made, muscle remains atrophic.
In CNS, regeneration is not inhibited by glial scar formation and growth-inhibiting proteins.

Front 61

What are some ways to improve CNS regeneration?

Back 61

1) Prevent neuronal death by limited inflammatory response (ice?)
2) Induce CNS axon growth by implanting Schwann cells or PNS nerve at site
3) Overcome environmental factos by preventing scar formation or block activity of growth-inhibiting proteins.

Front 62

Define withdrawal reflex.

Back 62

A type of reflex that can function without ascending brain activity

Front 63

what are the three layers of menings?

Back 63

1) dura mater: dense connective tissues
2) arachnoid: loose connective tissue
3) pia mater: ensheathes blood vessels

Front 64

What are the functions of cerebral spinal fluid?

Back 64

"shock absorber"
cushion brain from skull
transportation of nutrients and waste

Front 65

What produced CSF?

Back 65

Choroid plexus- in combination with the neighboring ependymal cell to produce cerebral fluid.

Front 66

What is hydrocephalus? How does it arise? How to treat it?

Back 66

* hydrocephalus is due to excess CSF accumulation in the brain.
* Cause by block of CSF flow or overproduction of CSF
* can be treated by shunting excess CSF into abdominal cavity

Front 67

What is meningitis?

Back 67

infection or inflammation of the meninges and CSF, cause by virus, bacteria

Front 68

CIRCULATORY SYSTEM

Back 68

CIRCULATORY SYSTEMS

Front 69

What are the three layers of arteries and veins from lumen outward and their respective components?

Back 69

1) Tunica intima:squamous epithelium
2)tunica media: smooth muscle
3) tunica adventitia: connective tissues

Front 70

Be familiar with the three types of arteries, veins, and capillaries.

Back 70

Arteries:
1) Elastic (large)
2) Muscular (med)
3) Arteriole (small)

Veins:
1) large veins
2) medium veins
3) venules

Capillaries:
1) Contiunuous
2) Fenestrated
3) discontinuous

Front 71

Name 5 kinds of glial cells and their functions.

Back 71

1) Schwann cells / Satelitte cell (PNS_
2) Oligodendrocytes (CNS)
3)Ependymal cells (CNS)- CSF fluid
4) Astrocytes (CNS)- contribute to brain blood barrier
5) Microglia (CNS & PNS)-

Front 72

What are the two types of astrocytes?

Back 72

1) protoplasmic -in grey matter
2) fibrous astrocytes - in white matter

Front 73

Paracrine signaling vs autocrine signaling

Back 73

* Local- diffues via interstial fluid
* via receptors