Concept………
• The Health of an organism depends on the
resources available to it .
• Food is an essential requirement for living
organisms.
• Understand the process by which energy is
obtained in various types of organisms
through nutrition.
Assessments
– Criteria C: Unit Test
• Criteria A + B: Written work based on different
topics eg, stem cell research, GM cells in
modern world etc.
• Criteria F: Attitude
Unit 2
• Nutrition
•
2n ESO
– Area of Interaction: Health and Social Education
– Criteria: B,C, E, F.
• Structure of living things, plant and animal cells,
types of nutrition, Animal digestion and
respiration. Plant nutrition (photosynthesis and
respiration). Observation of cells under a
microscope.
•
Unit 2
Why we eat.
How is life affected by the physical
environment ?
What is a living thing ?
• What is it made of ?
• How does it remain alive ?
• Where does it get energy from to move and
grow?
Living organisms…..
Organisms are made up of organ systems ….can
you name any ?
• Organ systems are made up of organs
……......can you name any ?
• Organs are made up of tissues…….can you
name any ? E.g. muscle , ……….
• Tissue is made up of………Cells
• Cells – Tissues – Organs – Organ Systems - Organism
Cell Lab.
•
•
•
•
1. Get to know the microscope .
2. Understand how it works.
3.Look at prepared slides
4. Make a slide
The Microscope
• A microscope magnifies …..it makes things
look ….much
bigger.
Microscope
Label your diagram
Label the parts using the key words below:
Arm , stage , stage clips ,
high power objective lens,
low power objective lens , ,
eye-piece , mirror , base, Diaphragm,
coarse adjustment knob,
fine adjustment knob
Stage adjuster
Lab. Task – Make a slide
• Make a slide of cheek and onion cells .
• Draw what you see through low power lens
and high power lens
Preparing a microscope slide
• Method
1.Place 2 slides and 2 coverslips on a tile .
2.Wipe a cotton bud on the inside of your cheek.
3.Smear it onto one slide.
4.Gently lower coverslip over specimen ,at an
angle, using a mounted needle.
5.Repeat step 2 and 3 with the second slide ,but
place one drop of blue stain onto your sample
before you put the coverslip on .
Lab Report Key words
•
•
•
•
•
•
•
Magnify
Iodine
Mounted needle
Methylene blue
Cover slip
Slide
Microscope
Draw each of the slide cells
6. View under LOW magnification and draw
7.View under higher magnification and draw
8. Compare the stained and unstained cells
9. Compare the cells under high and low
magnification.
Cheek cell (animal cell)
Making a plant cell slide
Method
•
•
•
•
•
•
•
•
•
1.Place clean slide and coverslip on tile .
2.Place a small piece of onion tissue on slide.
3.Put one drop of iodine stain on tissue. Warning
4.Carefully lower coverslip over tissue.
5.Use tissue to mop up extra liquid on slide
6.View under low then high power lens.
7. Repeat above steps but use water instead of iodine
7. Draw what you see . High/Low mag
with/without iodine
Onion Cell (Plant cell)
What do cells look like….?
Structure and function of cell
Part
Function
Cell membrane
Allows substances in and out of cell
Nucleus
Controls cell activities , contains DNA
Cytoplasm
Jelly-like substance where chemical reactions take place
Mitochondrion
Supplies energy to the cell
Lysosome
Contains digestive enzymes
Chloroplast
Contains chlorophyll for photosynthesis (only in plants)
Vacuole
Dumping and waste area (mainly in plants)
Video clip
• Cells …………..(Sandisk Pink)
Making a model Animal Cell and a
Plant cell
• Method –
• 1. Take 2 plastic bags (one for plant one for animal =
cell membrane
• 2. Fill it with cytoplasm
• (Using a spoon ¾ fill the bag with paste .)
• 3. Add a Nucleus .
• 4.What do you need to add to the other one
to make it a plant cell ?
Two types of cell make up all of life….
How do they get their nutrition ????.
1.……Prokaryotic cells ……cells with
NO nuclear membrane
( very simple cells like bacteria)
•2.…..Eukaryotic cells ……cells have a
nuclear membrane
Prokaryotes
(bacteria)
Bacteria are single celled organisms that
have successfully colonized every area of the
planet .
There are harmless bacteria ,
beneficial bacteria that aid digestion and
harmful bacteria that cause disease
Bacteria look like this……
Actually there are 5 Kingdoms
• Prokaryotic Cells – (without nuclei )
• 1. Kingdom Monera –(10,000sp.) Unicellular bacteria +
cyanobacteria
• Eukaryotic cells – (with nuclei )
• 2. Kingdom Protista (250,000 sp.) – unicellular & multicellular
protozoans and algaes
• 3. Kingdom Fungi – (100,000 sp.)
• 4.Kingdom Plants – (250,000 sp.)
• 5.Kingdom Animals-(1,000,000 sp. )
………………………………………………...Watch the 5 kingdoms video clip
LEARN **************
Cell Theory
• 1. All living things are made of cells .
• 2. Cells are the basic unit of structure and
function.
• 3. Cells are produced by cells
Research
• Has the development in scientific research
into the cell and cell theory helped to develop
new methods into agriculture and medicine ?
• Stem cell research and Genetically modified
crops?
• What do you understand by this?
Genetically modified crops
Feed the World
Stem cell research
Bacteria
• Heterotrophic bacteria are a type of bacteria
that take the sugars they need to survive and
reproduce from their environment, rather
than making the sugars themselves from
carbon and hydrogen. E.g. Escherichia coli
• Bacteria that do produce their own sugars
from carbon and hydrogen are called
autotrophic. E.g. Cyanobacteria
E. Coli Bacteria
cyanobacteria
All Cells need food in order to work
properly.
• All cells need food (nutrition )to provide them
with energy to survive ,grow and repair.
• Cells get nutrition by breaking down food (organic
matter ) by eating organisms
(Heterotrophic nutrition)
OR
• By taking inorganic substances and making it
themselves.
(Autotrophic nutrition)
Prokaryote/Eukaryote Cell Nutrition
Research the following types of nutrition that these
cells require .
• Prokaryote Cell
Eukaryote cell
• A). Autotrophic nutrition - (Holophytic)
• B) Heterotrophic nutrition – Holozoic
- Parasitism
- Saprophytes
C) Detritivores
Types of Heterotrophic Nutrition
• Heterotrophic nutrition is nutrition obtained by digesting organic
compounds. Animals, fungi, many prokaryotes and protoctists are unable
to synthesize organic compounds to use as food. They are known as
heterotrophs.
• Heterotrophic organisms have to acquire and take in all the organic
substances they need to survive. All heterotrophs (except blood and gut
parasites) have to convert solid food into soluble compounds capable of
being absorbed (digestion) The three main types of heterotrophic
nutrition are:
• Holozoic nutrition: Complex food is taken into a specialist digestive system
and broken down into small pieces to be absorbed. This consists of 5
stages, ingestion, digestion, absorption, assimilation and egestion.
• Saprobiontic/saprotrophic: Organisms feed on dead organic remains of
other organisms.
• Parasitism: Organisms obtain food from other living organisms (the host),
with the host receiving no benefit from the parasite. E.g. Head Lice
Detritivores
• detritivore (d-trt-vôr)
• An organism that feeds on and breaks down
dead plant or animal matter, returning
essential nutrients to the ecosystem.
Detritivores include microorganisms such as
bacteria and protists as well as larger
organisms such as fungi, insects, worms, and
isopod crustaceans. In a food chain,
detritivores are primary consumers.
Autotrophic Nutrition
• In Plants – Green Plants make food by a
process called Photosynthesis .
• What can plants use to make food ????
• They are stuck in the soil !!!!
• Two types of reaction occur during
metabolism –
•
Anabolic reactions –(build up reaction)
•
Catabolic reactions –(breakdown reaction)
Anabolic reactions – taking what is in
your food and forming large complex chemicals
…..for growth
Catabolic reactions – breaking down sugars or
fats for energy