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Mid-Year
Review
Outline
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Cells
Organisation of Matter
Fluids and Pressure
Musculoskeletal system
Respiratory system
Cardiovascular system and Blood
Constraints & Deformations
Cells
What are cells?
• Cells are the basic unit of all living
things
• 2 main types of cells:
o Animal
o Plant
Cell Components
• Cell membrane
o The cell membrane holds the cell together and allows nutrients in the cell
• Cell wall
o Cell walls are only in plant cells
o They make the cell strong and rigid
• Cytoplasm
o Cytoplasm is the watery gel inside a cell that holds the organelles
• Mitochondria
o Mitochondria is an ORGANelle that releases energy from food
• Chloroplasts
o Chloroplasts are only in plant cells
o They contain chlorophyll, which helps make energy/food from sunlight
Cell Components (2)
• Nucleus
o The nucleus controls the cell (cell’s “brain”)
• Chromosomes
o Chromosomes are inside the nucleus and are made of genes
(DNA)
o Genes decide the cells traits and activities (heart cell, eye cell
(color))
• Nuclear membrane
o The nuclear membrane allows substances to pass in and out of
the nucleus
• Vacuole
o Vacuoles are spaces in the cytoplasm (gel) where food and
chemicals are stored
Cellular Specialization
• Although all animal cells have the same
basic structure, different cells perform
different functions
o We call this cellular specialization
• Organization:
Cells
Tissue
Organ
System
Living
organism
Cellular Organization
• Cells
o Smallest unit of life
• Tissues
o A group of cells with the same function and structure
o Types of tissue: epithelial, connective, muscle, nerve
• Organs
o Structures composed of 2 or more tissue types
• Systems
o Multiple organs working together for a common purpose
• Organisms
o All the organ systems together to create one body
Matter
• Matter is anything that has volume and mass
• REVIEW: particle model
Phase Changes
• How do you go from one phase to another?
• Solids
States of Matter
o Have a defined shape
o Molecules are arranged in a regular pattern
o Molecules are held firmly in place and tightly packed together
• They can vibrate a tiny bit
• Liquids
o The molecules flow easily around each other
o Take on the shape of their container
o Weak attractive forces between molecules keep them from flying
apart
• Gases
o Molecules fly around in all directions at great speeds
o Practically no attractive forces between molecules
Fluids & Pressure
Hydraulics and Pneumatics
Fluid
• A fluid is any substance that has the capacity to
flow and assume the form of the container into
which it is poured
o Gases
o Liquids
Types of Fluids
• There are 2 types of fluids:
o Compressible fluids
• A fluid with a volume that can vary (gases)
• Example: air
o Incompressible fluids
• A fluid with a volume that doesn’t really vary
(liquids)
• Example: water
Pressure
• Pressure is the result of a force applied over a
surface (measured in pascals [Pa])
o Force: an action that modifies the movement of an object
or causes a deformation (N)
o Surface area: the surface dimension of an object (m2)
𝐹
𝑃=
𝐴
• The stronger the force applied to a certain area,
the greater the pressure
• The larger the area over which a force is applied,
the lower the pressure
Pressure in Fluids
• Pressure in fluids is dependent on collisions
• Factors affecting the number of collisions:
o Number of particles
o Temperature
o Volume
• At constant temperature, the volume of a
compressible fluid is inversely proportional to
pressure
o V ↑ then P↓
Think about when your breathe
o V ↓ then P↑
Fluid Movement
• Remember: fluids move from areas of high pressure
to areas of low pressure
o Think about breathing and oxygen/carbon dioxide
diffusion
Musculoskeletal
System
Bones and Joints
Musculoskeletal System
• The musculoskeletal system is what makes
movement possible
• It includes:
o Bones
• Solid organ that forms the skeleton
o Muscles
• Have the ability to contract, causing the body
or internal organs to move
o Joints
• The junction between two or more bones
5 Functions of Skeleton
• Movement
o You can move your arm, leg, etc
• Support
o The reason we can stand upright
• Protection
o Rib cage protects your internal organs
• Makes red blood cells
o The marrow is where your blood cells and platelets are
made
• Storage
o Internal cavities of bones store fat
o Bony tissue stores minerals (e.g. calcium)
Bone Structure
Connectors
• Ligaments
o Connects bones to other bones
• Tendons
Lig… sounds like
“like”
Bone to bone =
same
o Connects muscle to bone
• Cartilage
o Acts as a cushion to protect the bones or keep
certain passages open
• Ex: nose, rings in trachea
3 types of muscle
• Skeletal muscle
o The only voluntary muscles (we can control them)
o Connected to the bones of the skeleton
• Smooth muscle
o Makes up the wall of certain internal organs
o They are involuntary (they work without us thinking about it)
• Cardiac muscle
o The muscles that make up the heart
o Also involuntary
Rectus
abdominus
Movement
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Abduction – moving away from midline
Adduction – moving toward midline
Flexion – bending of body part
Extension – straightening of body part
Rotation – moving around its own axis
In abduction -> the b points away from the a
In adduction -> the d points towards the a
Respiratory System
Cellular Respiration
• Cellular respiration is the process whereby cells
extract the energy they need from nutrients such as
glucose
o This requires oxygen (O2)
glucose
C6H12O6
O2
Energy
CO2
H 2O
Respiratory System
• Respiratory system made up of:
o Respiratory tract
o Lungs
• Respiratory tract:
o
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Nasal passages
Pharynx
Larynx
Trachea
Bronchi
Respiratory System
Breathing
Respiration
• Goal:
o Extract oxygen (O2 ) from the air (for our cells)
o Expel CO2 (waste)
→ this gas exchange takes place in the alveoli
(miniature cavities filled with air that are
surrounded by tiny blood vessels)
Circulatory System,
Blood Pressure &
Blood
Blood
• Blood has a liquid component (plasma) in which
different formed elements are found:
o Red blood cells (erythrocytes)– carry oxygen
o White blood cells (leukocytes) – important for immunity
• Phagocytosis – the process whereby white blood cells
ingest and destroy certain organisms
• Responsible for creating antibodies
o Platelets (thrombocytes) – responsible for clotting blood
• Blood is the main mode of material transport
around the body:
o Oxygen, carbon dioxide, other wastes, nutrients, etc
Blood Types
• A person’s blood type is dependent on the antigens
present on the red blood cells
• A person can be either:
o
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A+
AB+
BAB+
ABO+
O-
Blood Transfusions
• These antigens play an important role in
blood transfusions (injecting blood from one
person into another):
o I cannot receive what I do not have
• Universal recipient
o AB+ (has all the antigen types: A, B, Rh)
• Universal donor
o O- (has no antigens)
The Heart
Aorta
Superior
vena cava
Right
atrium
Right
ventricle
Inferior vena
cava
Pulmonary
arteries
Pulmonary
veins
Left atrium
Right
ventricle
Heart & Blood Pressure
• The heart is the organ that is central to the
circulatory system – it pumps the blood around the
body
• When the heart fills with blood (low blood pressure)
o Diastole
• When the heart contracts to expel blood (high
blood pressure)
o Systole
Good blood pressure
120/80
Blood Vessels
• Blood vessels are divided into 3 categories:
o Arteries
• Carry blood away from the heart
o Veins
• Carry blood to the heart (viens)
o Capillaries
• The smallest blood vessels
• Have very thin walls that allow for gas
exchange between blood and cells of the
body
Constraints,
Deformations &
Material Properties
Constraints
• Mechanical constraint
o The stress produced within a material
when it is subjected to external forces
o 5 types:
• Tension
• Torsion
• Compression
You did this last year!
• Shearing
• Flexion/bending
Deformation & Properties
• Deformation:
o Constraints can have different effects on materials called
deformations:
• Elastic deformation (reversible- goes back to regular
shape after)
• Plastic deformation (keeps the shape it has been bent
into)
• Fracture (material breaks)
Links
• Linking
o The basic mechanical function provided by any
component that links two parts of an object
o A link has 4 characteristics:
• Direct or indirect
• Rigid or flexible
• Removable or non-removable
• Complete or partial
Direct vs Indirect
• Direct:
o Link connects parts without using some intermediary
material (no glue, screws, tape)
• Basically, the part fit together and come in direct
contact with one another
• Ex: LEGO pieces
Note: rivets are indirect
• Indirect:
o The connection between the 2 components requires
another fastener like glue or nails/screws
o The two parts do not hold together on their own, they
require an additional fastener
Removable vs NonRemovable
• Removable:
o The parts can be separated without damaging them or
the fastener
• E.g. a pen cap from the pen
• Non-Removable (permanent) :
o If the 2 parts are separated at least one of them (or the
fastener) will become damaged
• E.g. when things are glued together
Rigid vs Flexible
• Rigid:
o The link does not have any give; it is stuck in a particular
position/shape
• Flexible (Elastic):
o The link allows the parts it is connecting to change positions
or be deformed
• The link can undergo deformation and then return to its original
shape/position
• Usually: rubber or springs are involved
Complete vs Partial
• Complete:
o The link does not allow the parts to move independently of
each other
• If one part moves, the other will as well
• Partial:
o One part can move independently of the other
• If one part moves, the other one does not necessarily
o E.g. door and door frame
Let’s look at an
example:
Link between the two prongs:
Direct or indirect?
Rigid or flexible?
Removable or
non-removable?
• Complete or partial?
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