8 th Grade Science Content Strand 3

Transcription

1 8 th Grade Science Content Strand 3

2 3.a. Adaptations: traits that help survival & reproduction Make one card for each. 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. 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 Viral- cold, influenza, HIV, chicken pox Bacterial- tetanus, pneumonia, strep Fungal- athlete s foot, ringworm Protist- malaria Antibiotics treat How are pathogens spread bacterial diseases, NOT VIRUSES. through direct contact, body fluids, food, water, or animals.

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 Phenotype Genotype Physical appearance of a trait Ex. Brown 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 blended traits Incomplete dominance Red and white flowers= pink flowers both are expressed Codominance Black dog+ white dog= black and white dog

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

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

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

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.

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

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

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

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

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

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

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

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 C 6 H 12 O 6 + 6O 2 -> 6CO 2 + 6H 2 O + energy