Download Unit B: Cells and Systems - St. John Paul II Collegiate

Unit B: Cells and Systems - STS and Knowledge
1. Investigate living things; and identify and apply scientific ideas used to interpret their general
structure, function and organization
SF pp. 98
Investigate and describe example scientific studies of the characteristics of living
things (e.g., investigate and describe an on-going scientific study of a locally-found
organism)
Characteristics of Living Organisms
 Living organisms need energy, they get it from food
 Living organisms respond and adapt to their environment
 Living organisms reproduce so life can continue
 Living organisms grow
 Living organisms produce waste like carbon dioxide
SF pp. 99,
100-101, pp
141-144
Apply the concept of system in describing familiar organisms and analyzing their
general structure and function
Levels of organization:
Cells Tissues  Organs  Systems
The cell is the smallest, or basic, unit of every system. A cell is the smallest thing scientists
consider to be alive.
Cells with the same structure and function are grouped into tissues.
4 main types found in animals (p. 141
Muscle tissue: move the parts of the body
Nerve tissue: carries signals between the brain and other body parts to co-ordinate activities.
Epithelial tissues: protects the outside of the body and covers the internal structures, such as
intestines
Connective tissue: connects and supports different parts of the body, Maybe solid like bone
or fluid like blood.
3 Main types found in plants (p. 141)
Epidermal tissue: (skin) protects the outside of the plant.
Xylem tissue: vessels transport water absorbed by the roots, throughout the plant.
Phloem tissue: vessels transport the glucose to other parts of the cell.
Organs: distinct structures in your body that perform particular functions.
E.g. Brain, eyes, kidneys etc.
Systems: Organs form systems that help plants and animals function as a whole.
E.g. Roots and shoot system in plants.
Groups made of different tissues form organs.
Organs working together form systems.
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SF p. 99
SIA pp. 90
Illustrate and explain how different organisms have similar functions that are met in a
variety of ways (e.g., recognize food gathering as a common function of animals, and
note a variety of food gathering structures
Examples:
- plants gather food through roots and by bending; animals move around
- movement in the environment: birds have wings, whales have flippers
- food gathering structures: barnacles have tentacles, birds have bills
- breathing structures: gills vs lungs
2. Investigate and describe the role of cells within living things
SF p. 104
Describe the role of cells as a basic unit of life
Cell: the basic unit of every system. It separates all forms of life from non-living things. All
living things are made up of cells. Cells can be very specialized to suit a system in the
body.
SF pp. 115,
pp 138-140
Analyze similarities and differences between single-celled and multi-celled organisms
(e.g., compare, in general terms, an amoeba and a grizzly bear, a single-celled alga
and a poplar tree)
Multi-cellular: organisms made up of more than one cell or a system of cells
Unicellular: single celled organisms
Cells need to be specialized to meet different needs just like band needs to have different
instruments to play a variety of songs. Cells in multicellular organisms are said to be
specialized for different jobs.
The Advantages of being multicellular
-Unicellular organisms have to be able to move, eat, reproduce and respond to
environments. Because they depend on cell membranes the can only live in watery, food
rich environments.
Multicellular can live in a wide variety of environments; by specializing they can be much
more efficient.
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SF pp 121123, pp
104-114
SIA pp 103,
108-109
Distinguish between plant and animal cells (e.g. distinguish between cell walls and
cell membranes)
Magnifying: making something appear larger
Early Microscopes
Anton van Leeuwenhoek invented one of the first microscopes using different glass lenses.
He was able to magnify up to 300 times the size of an object. Robert Hooke was also
experimenting by looking at pieces of cork under magnification. He described what he saw
as cellulae “little rooms” giving us the Present-day word “cell”
Cells are the building block of life; All living things are made up of cells.
Types of Microscopes
Light Microscope: 2 000x magnification
Electron Microscope: 2 000 000x magnification (must be in a vacuum therefore dead cells
only)
*Know Parts of a Microscope Pg. 107 of book
SF pp 121123
Structures inside the cell are known as organelles
Cytoplasm: jelly-like material in which other parts of the cell float
Cell membrane: surrounds the cell and protects the cells contents
Cell wall: thick covering outside the cell membrane.
Nucleus: controls most of the cells activities
Vacuole: liquid filled part for storage; smaller and fewer in animal cells
Chloroplast: contains the green pigment chlorophyll.
Plant Cells
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Animal Cell:
*The functions carried out by the human body are the same functions that are carried out by
each individual cell.
SF pp 128137
SIA pp 115116, 119
Describe the movement of gases and liquids into and out of cells during diffusion and
osmosis, based on concentration differences
Cell Membrane: Is like a border crossing. The Membrane is selectively permeable
meaning that it lets some things across but not others.
Permeable: lets everything through
Impermeable: lets nothing through
Diffusion: the random movement of particles from a high concentration to a low
concentration. The particle model (from Unit A) helps us understand diffusion!
Diffusion in cells: cells burn oxygen and make carbon dioxide so there is a high
concentration of CO2 inside a cell (wanting to diffuse out) and a low concentration of oxygen
(therefore oxygen wants to diffuse in). Diffusion in many cases allows for a movement of
particles through a membrane without a cost of energy from the cell.
*About 70% of a cell’s content is water.
Osmosis: Diffusion of water through a selectively permeable membrane. Water moves from
a high concentration to a low concentration.
Fluid Movement in Plants
All the water in a plant is connected from cell to cell, water taken in by roots pushes water
up (through osmosis) and water evaporating off of leaves pulls water (also through
osmosis).
Vascular tissues (2 types)- like blood vessels for a plant!
 Phloem tissue: transports sugars manufactured in the leaves to the rest of the
plants
 Xylem tissue: conducts water and minerals absorbed by the roots cells to every cell
in the plant.
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Root hairs: Tiny hair-like roots that serve to increase the surface area in which osmosis can
take place.
From the root hairs water is absorbed into the xylem tissue, to the stems, then to the leaves.
Once into the leaves it is used by the chloroplasts for photosynthesis.
Stoma: (stomata) are openings in the bottom of leaves that let air in and out. Controlled by
the guard cells.
Transpiration: Loss of water from a plant through evaporation from the leaves and stem.
SF pp. 140142
Examine plant and animal structures; and identify contributing roles of cells, tissues
and organs
Example: Digestive System
1. Many up of many organs such as the intestines and the stomach
2. In the stomach, muscle tissue moves to mix stomach contents. Epithelial tissue
lines the stomach. Connective tissue helps hold the shape. Nerve tissue
coordinates the activities of the stomach.
3. The connective tissue is made up of loose, fibrous sheets that connect and support
the body.
3. Interpret the healthy function of human body systems, and illustrate ways the body reacts to
internal and external stimuli
SF pp. 146147
SIA pp. 9397
Describe, in general terms, body systems for respiration, circulation, digestion,
excretion and sensory awareness(e.g., describe how blood is circulated throughout
the body to carry oxygen and nutrients to the body’s various tissues and organs
Digestive System: used to take in food and break it down into usable energy then pass the
waste out of the body.
Respiratory system: used to take in oxygen and give off carbon dioxide in the lungs.
Circulatory System: transports food and oxygen to different parts of the body and carries
waste products out of the body
SF pp 148152, 158
Describe, in general terms, the role of individual organs and tissues in supporting the
healthy functioning of the human body (e.g., the role of the lungs in exchanging
oxygen and carbon dioxide, the role of bronchia in providing a passageway for air
Respiratory  Circulatory
AIR PATHWAY
Bronchus tube  bronchioles  alveoli  capillaries
- The respiratory system brings moves the air in and out of the lungs and the circulatory
system picks up oxygen from the lungs while dropping off carbon dioxide.
- The circulatory system carries the oxygen to the parts of the body that need it via diffusion.
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Digestive Circulatory
FOOD PATHWAY
Mouth  Stomach  Small Intestine  bloodstream via villi
Villi: (Villus, plural) each villi contains a network of capillaries which absorb the digested food
into the blood stream, much the same way as the alveoli.
Food provides Nutrients in the form of Carbohydrates, Fats, proteins, vitamins, minerals
and water that provide Energy and materials used for Growth, Development, and Repair.
SF pp 154155
Describe ways in which various types of cells contribute to the healthy functioning of
the human body (e.g., describe the roles of individual cells in nerves, muscle, blood,
skin and bone)
Circulatory System Cells
Red Blood Cells: contain hemoglobin and carry oxygen.
White Blood Cells: defend the body against sickness/disease and help blood clot
Hemoglobin: iron rich chemical found in blood that attracts oxygen. This helps the blood
carry more oxygen than it otherwise would.
Plasma: liquid portion of the blood. It carries food, waste, hormones and blood cells.
Platelets: prevent blood loss
Blood Vessel: part of a complex network of tubes/passageways that serve to bring things
from the external environment to the internal environment.
 Veins pump blood to the heart
 Arteries pump blood away from the heart
SF pp 151
Describe changes in body functions in response to changing conditions (e.g.,
changes in heart rate in response to exercise, change in metabolism in response to
lower temperature, reflex responses to stimuli)
Sensory Awareness System
1. Temperature: A stable internal environment in your body is desired!
Cold: shivering makes muscles quiver and generates heat. Hair stands on end because of
small muscle contractions.
Heat: blood vessels in your skin expand to increase blood flow to the surface and release
heat – it’s why you get a red face when you run!
2. Exercise
Increases heart rate, and thus blood flow. Blood is diverted away from the digestive system
and towards muscles so they can obtain oxygen.
3. Panic
Feeling ‘afraid’ is a reaction based on your endocrine system and your nervous system.
- heart rate increases
- blood is diverted to needed muscles (ex: to escape, you need your leg muscles!)
- your mouth becomes dry
4. Reflexes
Your nervous system (brain, spinal cord and nerves) send signals to your body parts in
response to stimuli.
Example: the doctor hits your knee with his small hammer – what happens?
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4. Describe areas of scientific investigation leading to new knowledge about body systems and to
new medical applications
SF pp. 157,
159, 160
Identify examples of research into functions and dysfunctions of human cells, organs
or body systems
Investigate and describe factors that affect the healthy function of the human
respiratory, circulatory and digestive systems (e.g., investigate the effect of illness,
aging or air quality on the function of the respiratory system)
Causes of Digestive System disorders
-Low fiber over a prolonged time (skipping meals or eating high sugars) can be a cause of
colon cancer
-Long term stress, smoking or excessive use of aspirin and alcohol can lead to ulcers.
Disorders of the Respiratory System
Cilia: small hair-like projections that remove airborne particles in the lungs
Poison in cigarettes and pollution irritates the lining of the respiratory system causing extra
mucus to be produced, which is removed by coughing.
Bronchitis: inflammation of the bronchial tubes, if prolonged over time can cause
emphysema.
Lung Cancer: caused by Tar in smoke, which makes certain cells grow out of control
Common Problems with Circulatory System
-Hypertension (high blood pressure)
-Strokes
-Heart attacks
SIA pp 154158
Describe ways in which research about cells, organs and systems has brought about
improvements in human health and nutrition (e.g., development of medicines;
immunization procedures, diets based on the needs of organs, such as the heart)
Vaccines
Louis Pasteur identified ‘germs’ as living cells.
- the cause of many diseases, like smallpox
- vaccines are inactive versions of the germs that cause the disease
- the body learns how to fight off a disease when a small amount of germ cells are
introduced
Nutritional Research
- early explorers developed scurvy, which is a disease characterized by bleeding
gums, loose teeth, unsteady gait and sores that would not heal
- a lack of vitamin C in the diet was determined to be the cause
- food affects the functioning of many organs
o fat turn into cholesterol, which can build up in the walls of arteries
o bacteria in food can cause the mucus layer in your stomach to break down
– this leads to ulcers
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