7th Grade Tasks - Life
All life on Earth is in cells.
Some life is unicellular, one cell.
Most life you know of is multicellular, lots of cells.
Try to name at least 3 types of each
How can you tell if something is alive?
Task B-2 10-2
have organized systems
grow and develop
respond to stimulus
homeostasis - internal environment
organisms - living things are made of organic matter
Define life -
Task B-3 10-3
1. Where does the energy come from that powers life on Earth?
2. What do we call the ability to keep the
right temperature and conditions inside a cell?
3. Why do you eat?
4. What happens when you touch a hot stove?
Task B-4 10-4
Unicellular organism reproduce by splitting into two.
Multicellular organisms reproduce by exchanging
genetic material with a mate.
Task B-5 10-7
There is internal stimulus, like hunger.
There is external stimulus, like light, heat and sound.
1. Do you know of any plants that can respond to external stimulus?
2. How do humans respond to external heat for homeostasis?
3. How do dogs respond to external heat for homeostasis?
Task B-6 10-8
All life on the Earth is classified into three DOMAINS:
Bacteria- unicellular simple organisms, no nucleus
Archaea - unicellular that resemble early life,
live in extreme environments, no nucleus
Eukarya - unicellular or multicellular organisms,
all life you know, has a nucleus
TASK B-7 10-9
SPECIES - Homo sapiens
1. What type of life makes its own food?
2. What type of life are humans (kingdom)?
Task B-8 10-10
Linnaeus was the first scientist to group organisms into kingdoms.
He also used binomial nomenclature, which means two names.
It is the genus then species names.
Dogs are canis lupus familiaris.
Coyotes, wolves, and dogs are very closely related,
they can all interbreed.
Task B-9 10-11
A species is a group of organisms with similar traits
and can produce fertile offspring.
A genus is a group of similar species.
There are no other human species living today.
Did King Phillip Come Over For Good Spaghetti
Domain Kingdom Phylum Class Order Family Genus Species
Task B-10 10-15
A dichotomous key is used to identify organisms.
It uses a series of questions to narrow the choices.
A cladogram is a branching diagram that show
relationships between organisms.
The closer organisms are on the diagram,
the closer related they are.
Task B-11 10-16
In the 1600's Robert Hook and
Anton Leeuwenhoek made the first microscopes.
Microscopes magnify objects so we can see very small things.
Life began once on the Earth, ALL life is related!
It was all single-celled life for 2 billion years!
TASK B-12 10-17
The six kingdoms we recognize today are:
eubacteria - single celled, with a simple nucleus, some make food
archaebacteria - single celled ancient life, lives in extremes,
without nucleus, some make food
protista - single celled, has a nucleus, found in water,
microscopic, some make food
TASK B-13 10-18
fungi - single or multicellular, with a nucleus,
found everywhere, can't make food
plants - usually multicellular, found everywhere,
has a nucleus, makes food
animals - multicellular, has a nucleus,
found everywhere, can't make food
TASK B-14 10-21
Cell membrane - the layer that stops most things
from entering a cell. Think of a balloon filled with water.
Cell wall - the outermost layer of many
cells that gives structure and protection.
Think of the water balloon in a box.
Animal cells lack cell walls.
1. What gives animals structure?
TASK B-15 10-22
A compound microscope is a light microscope that
uses more than one lens.
An electron microscope can "see" things 1000 times
smaller than a light microscope, uses a stream of electrons.
1. What theory did the invention of the microscope help to happen?
Task B-16 10-23
Micro-organisms can make people sick.
"Cell Theory" states that all life is found in cells.
Microbes kill more people than any other single cause.
1. Why should you wash your hands before eating?
2. Where in your house are the most germs found?
TASK B-17 10-24
A vaccine is made from very small amounts of weak
or dead germs that can cause diseases —
for example, viruses, bacteria, or toxins.
It prepares your body to fight the disease faster
and more effectively so you won’t get sick.
Vaccines do NOT cause autism.
1. Why do we have to wear shoes at stores?
2. Do you know any diseases that vaccines have prevented?
- Chickenpox (Varicella)
- Flu (Influenza)
- Hepatitis A
- Hepatitis B
- Hib (Haemophilus influenzae type b)
- HPV (Human Papillomavirus)
- Polio (Poliomyelitis)
- Rubella (German Measles)
- Shingles (Herpes Zoster)
- Tetanus (Lockjaw)
- Whooping Cough (Pertussis )
TASK B-21 10-25
Why do we cover our mouths when we sneeze?