Support system Flashcards
1
Q
What is the innermost basic structure of a plant called?
A
Pith
2
Q
Describe the structure of the sclerenchyma
A
Dead cells with very thick, lignified secondary walls
3
Q
What sort of tissue is the pith composed of?
A
Parenchyma
4
Q
What sort of tissue is the cortex of the plant composed of?
A
Collenchyma
5
Q
What sort of plant tissue surrounds the vascular bundles?
A
Sclerenchyma
6
Q
What is the primary purpose of the tap root?
A
Anchorage and stability
7
Q
Describe the structure of a hydrostatic skeleton
A
Capsule of fluid surrounded by 2 layers of muscle
Fluid filled cavity acts as a rigid column on which muscles act
8
Q
Give an example of an animal with a hydrostatic skeleton
A
Earthworm
9
Q
What is the exoskeleton of an arthropod composed of?
A
Chitin, a polysaccharide
10
Q
What are the 2 kinds of endoskeleton?
A
Cartilaginous
Bony
11
Q
What is an osteon?
A
The fundamental functional unit of compact bone
Layers of bone matrix surrounding a central canal
Arranged into columns around an artery
12
Q
Name the 5 types of bone, based on shape
A
Short
Long
Flat
Sesamoid
Irregular
13
Q
Give an example of an irregular bone
A
Vertebrae
14
Q
Give an example of a flat bone
A
Ribs
15
Q
Give an example of a long bone
A
Femur
16
Q
Give an example of a short bone
A
Carpals
17
Q
Give an example of a sesamoid bone
A
Patella
18
Q
From top to bottom, what are the 3 sections of a long bone?
A
Epiphysis
Diaphysis
Metaphysis
19
Q
Where is yellow marrow found in a long bone?
A
Medullary cavity
20
Q
What are the 2 epithelial layers of a long bone called?
A
Periosteum
Endosteum
21
Q
What structure is found in spongey bone? What is its purpose?
A
Trabecullae -
Minimises weight
Aligns along lines of principle stress
22
Q
State Wolff’s law
A
Bone grows and remodels in response to the forces or demands placed upon it
23
Q
What are the 3 types of bone cell?
A
Osteoblasts
Osteoclasts
Osteocytes
24
Q
Describe the structure and function of osteocytes
A
Stellate
Mature bone cells
They sense loading and communicate
25
Describe the structure and function of osteoclasts
Multinucleated cells derived from monocytes
Found in the endosteum
Secrete acids and enzymes that remove bone
26
Describe the structure and function of osteoblasts
Immature bone cells found on surfaces, the periosteum and the endosteum
They secrete osteoid, an organic bone matrix
27
What is the opposite of osteoporosis?
Osteopetrosis
28
What is osteoporosis?
A condition where bones become weak and brittle due to loss of bone mass and density.
Caused by an imbalance between bone resorption (by osteoclasts) and formation (by osteoblasts).
29
What is osteopetrosis?
A rare genetic disorder where bones become abnormally dense and hard.
Caused by defective osteoclasts that fail to resorb bone properly
30
What would happen to a bone without mineral vs a bone without collagen?
Without collagen it would become brittle and stiff, without minerals it would become bendy
31
What structures are involved in the axial skeleton?
Skull
Vertebral column
Ribs
Sternum
32
How many curvatures are there in the vertebral column?
4
33
Approximately how many bones are there in the skull?
22
34
Give the structures of the vertebral column and how many of each, from top to bottom
7 cervical
12 thoracic
5 lumbar
Sacral and coccyx
35
How many pairs of ribs are there in humans? How many true and how many false?
12 pairs
7 true
5 false
2 floating
36
Name the 6 kinds of synovial joints and give examples
Ball and socket - hip
Hinge - knee
Plane - wrist
Pivot - neck
Saddle - thumb
Condyloid - fingers
37
What is the most immovable kind of joint?
Fibrous
38
Describe the structure of fibrous joints, and give an example
Bones joined by dense connective tissue (mostly collagen)
Sutures in the skull
39
Give an example of a cartilaginous joint
Intervertebral discs, pubic symphysis
40
Describe the structure of a cartilaginous joint
Bones connected by cartilage (hyaline or fibrocartilage)
41
Describe the structure of a synovial joint
Bones separated by a fluid-filled synovial cavity, surrounded by an elastic capsule
Ends of bones are covered with articular cartilage
42
Joint mnemonic!
Fibrous = Fixed, Cartilaginous = Cushion, Synovial = Sliding
43
What does a primary cartilaginous joint contain?
Hyaline cartilage only
44
What does a secondary cartilaginous joint contain?
Mainly fibrocartilage, sandwiched between 2 layers of hyaline cartilage
45
Give an example of a primary cartilaginous joint
1st sternocostal
46
Give an example of a secondary cartilaginous joint
Intervertebral disc
47
What is the matrix composition of hyaline cartilage?
Mostly type II collagen + ground substance
48
What is the matrix composition of fibrocartilage?
Rich in type I collagen + some ground substance
49
50
What are the three types of muscle tissue?
Skeletal (striated, voluntary), Cardiac (striated, involuntary), Smooth (non-striated, involuntary)
51
What are the three principle functions of skeletal muscle?
Movement, Posture, Heat production
52
How does skeletal muscle contribute to heat production?
High metabolic activity generates heat; shivering increases this
53
What are the two main components of muscle?
Contractile cells and connective tissues
54
What is a muscle belly?
The fleshy part of the muscle responsible for contraction
55
What connects two muscle bellies in a digastric muscle?
A tendon
56
What is the origin of a muscle?
The more stationary (usually proximal) attachment point
57
What is the insertion of a muscle?
The more mobile (usually distal) attachment point
58
What are the 3 classes of levers? What kind is most common?
1st class, 2nd class, 3rd class (most common in the body)
59
Do all muscles attach bone-to-bone?
No – some attach bone-to-skin (e.g. facial expression muscles)
60
What are skeletal muscle cells called?
Muscle fibres
61
What is inside muscle fibres?
Myofibrils made of actin and myosin filaments
62
What are the basic muscle shapes?
Circular, Parallel, Convergent, Pennate
63
What role does connective tissue play in muscle?
Bundles contractile cells, provides support and pathways for nerves & blood vessels
64
What connects muscle to bone?
Tendons
65
What is an aponeurosis?
A broad, flat connective tissue that acts like a tendon
66
What is the function of a tendon?
Transfers force of muscle pull to bone to produce joint movement
67
What are tendons composed of?
Mostly type I collagen; very high tensile strength
68
What are the two specialized tendon regions?
Myotendinous junction and osteotendinous junction (enthesis)
69
What is an isotonic contraction?
When a muscle contracts and changes length, resulting in movement of a joint.
70
What are two types of isotonic contraction?
Concentric (shortening) and Eccentric (lengthening)
71
What is a concentric contraction?
Muscle shortens while contracting (e.g. lifting a weight)
72
What is an eccentric contraction?
Muscle lengthens under tension (e.g. lowering a weight)
73
What is an isometric contraction?
Muscle contracts but does not change in length (e.g. holding a position)
74
What is an agonist (prime mover)?
The muscle that generates the main movement
75
What is an antagonist?
A muscle that opposes the agonist's movement
76
What is a synergist?
A muscle that assists the agonist
77
What is a fixator?
A muscle that stabilizes the origin of the agonist
78
How can a muscle play different roles?
It can act as prime mover, antagonist, fixator, or synergist depending on the movement
79
What type of muscle is striated and involuntary?
Cardiac muscle
## Footnote
Cardiac muscle is found in the heart and functions to pump blood.
80
What is the main function of skeletal muscles?
Movement of the body and/or its parts
## Footnote
This includes activities such as walking, running, chewing, and swallowing.
81
What are the two ends of a muscle called?
Origin and insertion
## Footnote
The origin is the stationary end, while the insertion is the more movable end.
82
What is a 1st class lever system in muscle mechanics?
Axis/joint in the middle, force at one end, load at the other end
## Footnote
This lever system helps pivot.
83
What is the primary characteristic of a 3rd class lever system?
Axis at one end, force in the middle, load at the other end
## Footnote
This system allows for rapid movement but cannot sustain it for long.
84
What are the components of a muscle?
Contractile muscle cells and connective tissues
## Footnote
These components work together to form the muscle belly and facilitate movement.
85
What are muscle fibres made of?
Myofibrils composed of actin and myosin filaments
## Footnote
Muscle fibres are long multinucleate cells that are the functional units of skeletal muscles.
86
Fill in the blank: Muscles that insert at an angle to the joint are called _______.
Pennate
## Footnote
This structure allows for stronger contractions due to more muscle fibres being packed in.
87
What type of contraction occurs when a muscle gets shorter?
Concentric contraction
## Footnote
This type of contraction is involved in movements such as abduction and adduction of the shoulder.
88
What is the role of an agonist or prime mover in muscle action?
Generates basic movement
## Footnote
The agonist is the primary muscle responsible for a specific movement.
89
True or False: Isometric contraction involves a change in muscle length.
False
## Footnote
Isometric contraction maintains a constant length while the muscle contracts.
90
What is the composition of tendons?
Mostly type 1 collagen
## Footnote
Tendons are designed for high tensile strength and transfer force from muscle to bone.
91
What is the function of fixators in muscle movement?
Stabilizes bones to allow movement to take place
## Footnote
Fixators ensure that the origin of the agonist remains stable during movement.
92
What is a digastric muscle?
A muscle with two bellies connected by a tendon
## Footnote
This structure allows for specific movements and force generation.
93
What characterizes unipennate muscles?
Stronger contraction with a shorter range of movement
## Footnote
Unipennate muscles have fibres arranged on one side of the tendon.
94
What is the role of connective tissues in muscles?
Surround muscle fibres and form tendons at either end
## Footnote
Connective tissues facilitate gliding and allow blood vessels and nerves to access muscle fibres.
95
What type of muscle is non-striated and involuntary?
Smooth muscle
## Footnote
Smooth muscle is found in various organs and is responsible for involuntary movements.
