1. 8th Grade Science Content Strand 3
Life Science
8th Grade Science Content Strand 3

2. traits that help survival & reproduction Make one card for each.
3.a. Adaptations:
Desert- nocturnal, needles on plants, large ears, burrow underground
Aquatic- long bodies, fins, gills, webbed feet, leaves that float
High altitude (mountains) - low oxygen
Cold climate- white fur, hibernation, fatty insulation, trees have needles
Grassland- feet for digging, flat teeth

3. 3.b. Cells FRONT: Differences in Plant and Animal Cells BACK:
Cell walls
Large vacuoles
Chloroplasts

4. 3. b. Cell Structures Put each on a different card
3.b. Cell Structures Put each on a different card. Structure on one side, function on the other.
Nucleus- controls activities, DNA
Cytoplasm- gel-like substance in cells
Cell membrane- controls what enters and exits
Mitochondria- RESPIRATION/energy for the cell
Chloroplast- PHOTOSYNTHESIS/in plants
Ribosomes- make proteins

5. 3.b. Cells (draw & label parts from previous slide)

6. 3.b. Types of Cells Put each on a different card.
Nerve- transmit information, found in brain, control senses
Bone- provide shape and support
Blood- carry materials all over body
Muscle- movement
Epithelial- protection,covering, found in skin

7. 3.b. Cells: Draw or print and put each on separate card.
muscle
neuron
epithelial
bone
blood

8. 3.c. Diseases Put type of pathogen on one side, examples on the other
cold, influenza, HIV, chicken pox
Viral-
tetanus, pneumonia, strep
Bacterial-
athlete’s foot, ringworm
Fungal-
malaria
Protist-
bacterial diseases, NOT VIRUSES.
Antibiotics treat
through direct contact, body fluids, food, water, or animals.
How are pathogens spread

9. 3.c. Viruses Require a host cell to reproduce
Causes host cell to make copies of virus (replicate)
Prevented by vaccines
Can change so are difficult to treat
Can spread through air (inhale), body fluids (blood), or vectors.

10. 3.c. FUNGUS Unicellular (one-celled)
Can spread through inhalation (mold) or direct contact (athlete’s foot)
May cause a rash on skin or breathing problems
Treatment: antifungal medicine

11. 3.d. Heredity Physical appearance of a trait Phenotype Ex. Brown
Genotype
Two alleles (letters) an organisms carries
Ex. BB, Bb, bb

12. 3.d. List genetic material from smallest to largest
Nitrogen base
Gene (allele)
DNA
Chromosome
Nucleus

13. 3.d. Pedigrees Squares- males- XY Circles- females- XX
Shaded- has trait
Half-shaded- carries trait
Clear- does not have or carry

14. 3.d. Incomplete and Codominance
Incomplete dominance
blended traits
Red and white flowers= pink flowers
Codominance
both are expressed
Black dog+ white dog= black and white dog

15. 3.e. Flow of Energy Producers Consumers Decomposers-
(autotrophs)- make own food
plants
Producers
(heterotrophs)- eat other organisms for energy
bear
Consumers
return nutrients to soil
mushrooms & bacteria
Decomposers-

16. 3.e. Food Webs Population Community- Ecosystem-
group of single species
same species
All the mice in a forest
Population
different species
all living things
All the rodents, snakes, deer, and trees in a forest
Community-
living and nonliving environment
The forest
Ecosystem-

17. 3.e. Food Webs Niche- In food webs: an organism’s role
More food= population increases
Fewer prey= fewer predators
Arrows show the flow of energy
In food webs:

18. 3.e. flow of energy Energy Pyramid Producer at bottom.
Less energy at each level.
Energy decreases by 10%.
Some is lost as heat.
Primary, secondary, tertiary consumers.
Energy Pyramid

19. 3.e. Energy Pyramid draw & label

20. 3.f. Selective Breeding Choosing organisms to mate for best traits
Examples: fast dogs, strong horses, muscular cattle, disease resistant corn
Selective Breeding

21. 3.f. Selective Breeding Pros of Selective Breeding:
better traits
easy to predict
Pros of Selective Breeding:
less diversity
more genetic diseases
time-consuming
Cons of Selective Breeding:

22. 3.f. Genetic Engineering Adding, replacing, or inactivating genes
Examples: bacteria produce insulin, weather-resistant crops, herbicide-resistant crops
Genetic Engineering

23. 3.f. Genetic Engineering Pros of Genetic Engineering:
disease-resistant crops, more nutritious foods, faster growing
Pros of Genetic Engineering:
may cause genetic defects, decreases diversity, could spread to other organisms.
Cons of Genetic Engineering:

24. Uses of Bacteria 3.g. Digest food Make yogurt and cheese
Break down oil spills and plastics
Can be genetically engineered
Uses of Bacteria

25. Uses of Yeast 3.g. Fungus Single-celled
Makes bread rise (carbon dioxide)
Makes alcohol (fermentation)
Uses of Yeast

26. 3.g.
Fungus
Produces cheeses
Antibiotics (penicillin)
Uses of Mold

27. 3.h. Respiration The process through which ALL cells get energy
Takes place in mitochondria
Uses oxygen to get energy from food
Releases some heat as wastes
Also called oxidation
C6H12O6 + 6O2 -> 6CO2 + 6H2O + energy
Respiration