Cells, Tissues, Organs

Question 1

What are the 5 characteristics of a cell

Answer 1

1) irritability : responds to stimulation
2) growth : goes through a life process of birth, development and death
3) spontaneous movement: movement originating and occurring within the cell
4) metabolism: takes in raw products, breaks them down and turns them into usable energy
5) reproduction: through cell division

Question 2

cell membrane

Answer 2

selectively permeable double layer of molecules surround the outside of the cell

typically comes into play with inflammation and respiration

Question 3

mitochondria

Answer 3

powerhouse of the cell, creates ATP to breakdown/give us energy

has own DNA/genome, only comes from mothers

10-20 in cell, not all the same can have different genomes

Question 4

lysosome

Answer 4

breaks down material

Question 5

golgi body

Answer 5

stores and delivers proteins

proteins for structural support, catalyze, antibodies, transport

Question 6

centrioles

Answer 6

assist in cell division and microtubule formation

Question 7

microtubules

Answer 7

support shape of the cell and movement of the organelles

Question 8

smooth endoplasmic reticulum

Answer 8

stores and releases enzymes and calcium for muscle contraction

Question 9

rough endoplasmic reticulum

Answer 9

produce, store and releases proteins

Question 10

ribosomes

Answer 10

synthesize protein as directed by genetic information

Question 11

Mitochondrial diseases

Answer 11

due to not defect in mitochondria, not enough energy due to lower levels / defects of ATP

as low as 1 in 4500 births

prevalence of dysarthria and dysphagia

genetic testing is the most reliable way to establish a diagnosis of a mitochondrial disorder

Question 12

what are the 4 types of cells

Answer 12

epithelial cells: selectively absorb molecules and ions (like in the gut) or cover surfaces and form selective barriers (like in the skin)

connective tissue cells: form and secrete various types of extracellular connecting, anchoring, and supporting structures of the body

muscle cells (aka muscle fibres): produce mechanical forces, which in turn produce movement

nerve cells: initiate and conduct electrochemical information

Question 13

What is a tissue and what are the 4 types

Answer 13

tissues are groups of cells that are similar in structure that band together with extracellular material and function as a unit

types:
1) epithelial tissue
2) connective tissue
3) muscle tissue
4) nervous tissue

Question 14

epithelial tissue

Answer 14

tissue that lines the internal and external surfaces of the body and the cavities of the body

very little extracellular material

described by shape, number of cell layers and location

Question 15

epithelial tissues: shape

Answer 15

shape:
- squamous (flat/plate like)
- cuboidal (cube)
- columnar (column)

Question 16

epithelial tissues: number of cell layers

Answer 16

• simple (1 layer)
• stratified (multiple layers)
• pseudostratified (looks like more than one layer but cells are just different sizes)

Question 17

epithelial tissues: location

Answer 17

epithelial tissue proper: forms the skin and internal membranes continuous with the skin

endothelial: lines blood and lymph vessels, made of simple squamous cells

mesothelial: 2 layers, lines internal body cavities, secretes seroud fluid
- pericardial (heart)
- pleural (lungs)
- peritoneal (abdomen)

Question 18

connective tissue

Answer 18

tissue that combines or holds structures together, supports the body, and aids in maintenance

fewer cells than epithelial tissue but more extracellular substance

classified based on composition of the extracellular matrix (loose, dense, specialized)

Question 19

connective tissue: loose

Answer 19

fills spaces and hold organs, anatomic structures, and other tissues in place

Question 20

connective tissue: dense

Answer 20

more tightly packed collagen and elastic fibers (collagen = structure and strength, elastin = stretchiness)

able to tolerate higher degrees of tension

3 types:
1) tendons: join muscle to bone, cartilage, or other muscles
2) ligaments: join bone to bone, bone to cartilage, or cartilage to cartilage
3) fascia: covers and separates muscles into functional groups

Question 21

connective tissue: specialized

Answer 21

cartilage has 3 types
1) hyaline: most abundant type, foudn in rib cage, larynx and nose
2) elastic: very flexible found in the outer ear (pinna, external auditory meatus), epiglottis, cuneiforms, corniculates
3) fibrous: slightly compressible and can withstand great amounts of pressure, found in regions that support body weight (intervertenral discs) and temporormandibular joint

bone: minerals are mixed with matrix which provide more rigidity and hardness

blood: extracellular material is primarily water

Question 22

muscle tissue

Answer 22

tissue that enables movement due to its contractility

3 types: cardiac, smooth, skeletal

Question 23

muscle tissue: cardiac (myocardium)

Answer 23

forms middle layer of the heart

responsible for pumping blood

involuntary control

each cardiomyocyte has one nucleus, looks striated, branches to connect with other cells, and has man mitochondria

Question 24

muscle tissue: smooth

Answer 24

forms muscular portion of the visceral organs (lower esophagus, stomach, lungs) and found within blood vessels

controls size, shape, and movements

nonstriated

involuntary control

Question 25

muscle tissue: skeletal (striated)

Answer 25

connects to skeletal framework and results in body movement during contraction

larger muscle diameters = greater strength

striated

voluntary control

predominant muscle tissue involved in speech production

Question 26

muscle tissue levels overall

Answer 26

1) muscle (organ)
2) fascicle (tissue), bundle of this forms the muscle
3) muscle fiber (cell), bundles of this forms the fascicle
4) myofibril (organelle): muscle contraction, made up of myofilaments

Question 27

nervous tissue

Answer 27

specialized to transmit information across distances via electrochemical means

found in brain, spinal cord, peripheral nervous system

2 types: nerve cells (neurons), glial cells
- neurons: send and receive infor
-glia: supportive function (maintain extracellular, provide structural support, nutrients to neurons)

Question 28

what are the structures in a neuron

Answer 28

cell body, dendrite, axon, myelin sheath, node of ranvier, axon terminal, synapse

Question 29

cell body

Answer 29

aka soma
metabolic centre for the neuron

Question 30

dendrite

Answer 30

specialized processes where the majority of afferent input is received

Question 31

axon (and hillock / terminal)

Answer 31

responsible for conducting the electrical impulse

axon hillock: the proximal portion of the axon where the soma and the axon meet

axon terminal: distal end of the axon which releases neurotransmitters

Question 32

myelin sheath

Answer 32

insulating layer that facilitates conduction of electrical signal to move more quickly along the axon

Question 33

node of ranvier

Answer 33

unmyelinated portions of the axon from which the action potential is observed to jump via saltatory conduction

Question 34

synapse

Answer 34

space where the elctrochemical signal passes from one neuron to the next

Question 35

what are the three main shapes of neurons

Answer 35

multipolar neuron: majority of brain neurons, motor function

bipolar neuron: special senses (ie taste)

unipolar neuron: sensory neurons

Question 36

cell

Answer 36

smallest living unit of the body

vary in shape, size and specific role

Question 37

tissue

Answer 37

groups of connected cells that share a similar function

each tissue has a characteristic role in processes related to communication

Question 38

organ

Answer 38

structure composed of at least two diferent tissue types that work synergistically