7 th Grade

1. 7th Grade TEKS Review

2. Photosynthesis • Radiant energy from the sun is converted to chemical energy during the process of photosynthesis. • T/F- Only plants perform photosynthesis. • Photosynthesis is performed mainly in the leaves of plants. • Chlorophyll (found in the chloroplasts) is green in color, and is where photosynthesis occurs. • Sunlight + Carbon Dioxide + Water Glucose + Oxygen

3. Tropism • Phototropism- response to light • Geotropism- response to gravity • Hydrotropism- response to water • Thigmotropism- response to touch

4. Living vs. Non-Living • Biotic- living, or once living • Exs: Trees, birds, decomposing leaves, fungus, people • Characteristics of Living Things: • Have cells • Have DNA • Grow and develop • Reproduce • Require energy • Sense and respond to stimuli • Abiotic- non-living • Exs: Sand, water, rocks, wind

5. Energy Transformation & Pyramid • Producers- plants; organisms that make their own food (usually by photosynthesis) • Consumers- an organism that eats producers or other organisms for energy • Primary consumers: herbivores • Secondary consumers: eat other consumers (& plants) • Tertiary consumers: consumer at the top of the food pyramid

6. Energy Transformation & Pyramid • Omnivore- consumer that eats plants & animals • Herbivore- consumer that eats plants • Carnivore- consumer that eats other animals • Decomposer- organism that gets energy by breaking down the remains of dead organisms or animal wastes

7. Energy Pyramid

8. Food Web

9. Food Chain

10. Ecosystems • Community- all the populations in an ecosystem • Species- all organisms of the same kind that adapted to a particular set of resources (called a niche) in the environment • Ecosystem- smaller part of the biosphere consisting of the organisms & non-living features that interact in an area • Population- made up of all the organisms in an ecosystem that belong to the same species

11. Biomes • Biome- large geographic areas with similar climates and ecosystems (desert, tundra, etc.)

12. Adaptations • Plants & animals adapt (change, adjust) to their environments in order to survive. • Adaptation examples: • Growing fur in cold environments • Coloring to blend into environment • Teeth designed for types of food (for tearing meat, grinding plants) • Eyes located on top of or on the sides of the head

13. Ecological Succession • Succession- the orderly changes an ecosystem goes through as it develops or regrows (happens over time) • Primary Succession- begins in an area that has not been previously occupied by a community (exs-exposed rock); there is no soil • Secondary Succession- begins on an area where a community has previously existed; is on soil • Pioneer Species- first species to begin growing in an area (moss & lichen) • Climax Community- the end of succession; it is in equilibrium with the environment

14. Homeostasis • Homeostasis- maintaining a stable internal environment • Our bodies respond to internal stimuli by vomiting and causing fever. This happens to maintain homeostasis. • In order to cool the body, we sweat. • In order to warm up, our body shivers.

15. Parts of a Flower

16. Asexual Reproduction • Needs only 1 parent • Genetic information isn’t mixed, so offspring are genetically identical to parents • Problems will always be passed on b/c offspring are clones of the parents • Examples: • Cuttings • Runners

17. Sexual Reproduction • Requires two parents • New individuals (offspring) are varied from parents b/c they are a mix of genetics from both parents • More genetic variation • Examples: • Fruit • Seeds

18. Genetics • Dominant trait-trait that, when present, will appear (represented in genotypes by capital letters) • Recessive trait- trait that does not appear when dominant traits are present (represented in genotypes by lower case letters) • Genotype- (AA, Aa, aa) alleles of a gene • Phenotype- (tall, short) an organism’s appearance