7 th grade science final study guide

1. 7th grade science final study guide

2. Cells • Active transport – cellular transportation using energy. • Passive transport – cellular transportation with no energy needed. • Mitosis – cell division in any cell except reproductive cell. • Meiosis – cell division in a reproductive cell. • Interphase – happens before cell division (mitosis). The cell grows and prepares to copy. • Stages of mitosis – prophase, metaphase, anaphase, telophase, • Cytokinesis – in a cell cycle after mitosis. When the cytoplasm divides and makes a new cell (daughter cell) • Cellular respiration – in the mitochondria where food turns into energy. • Cell- tissue- organ- organ system – organisms • Osmosis – diffusion by water. • Diffusion – movement of materials throughout cell in order to find equilibrium. • Endocytosis – when a molecule is too large to enter the cell membrane and is absorbed. • Exocytosis – when a molecule is too large to exit the cell through the cell membrane.

3. Cells • In what organelle does photosynthesis take place? • Which organelle controls all the cell’s functions? • Which organelle found in animal cells assist in cell division and has 9 groups of 3 arrangements of the protein fibers? • Which organelle is the powerhouse of the cell and gives the cell energy? • Which organelle is the highway system of the cell? • Which organelle is the protein producer for the cell? • Which organelle regulates what enters and exits the cell and is the doorway? • Which organelle known as suicide sacks is the clean up crew of the cell? • What is a fluid filled organelle that holds water, food, minerals and some waste. • What is inside the nucleus ? • What are two organelles found in plants and not animals? • Which organelle breaks down larger food molecules and rids the cell of waste? • What is attached to the rough E.R.? • Which organelle is the framework of the cell and gives strength and support? • Which organelle protects the nucleus and is selectively permeable? • What organelle carries materials throughout the cell? • What is produced inside the nucleolus? • What is the process of food turning into energy inside the cell? • Which organelle would be the water tower of the cell? • What is the cytosol plus the organelles called?

4. Cell Answers • Chloroplast • Nucleus • Centrioles • Mitochondria • E.R. • Ribosomes • Cell membrane • Lysosomes • Vacuole • Nucleolus • Cell wall and chloroplast • Lysosomes • Ribisomes • Cytoskeleton • Nuclear membrane • E.R. • Proteins • Cellular respiration • Vacuole • Cytoplasm

5. The Digestive Process Mouth - the mouth will prepare for digestion before food even enters. Just the smell, sight, or sound of food is enough to trigger saliva glands into action. teeth to break down food. Pharynx – food passes the epiglottis and past the voice box down the esophagus. Esophagus - pushed through a series of involuntary contractions (called "peristalsis") toward the lower esophageal sphincter otherwise known as LES. Stomach - strong muscular walls in the stomach acts as mixer and grinder, mechanically digesting our food while its acids and enzymes work to chemically digest it. In the end, our food is reduced to nothing more than nutritious liquid and small solid remnants. Small Intestine - After passing through the stomach, it's on to the small intestine where the nutritious liquid and small solid remnant are exposed to even more chemical digestion via enzymes from the pancreas and bile from the liver as peristalsis (the same involuntary contractions which occur in the esophagus) forces the food along its way. It is at this point that our body finally receives the nutrients from our food via the bloodstream, while the remainder makes it way to the colon. Colon (lg. intestines) - the colon’s job is to remove liquid from the non-nutritive food waste until it becomes solid and ready for excretion. By the time our food is ready for the toilet, it’s been approximately 36 hours since it originally entered our mouth.

6. The Circulatory System • Circulatory System • Capillaries – the smallest blood vessels in the body. • Arteries – blood vessels that carry blood away from the heart. • Veins – blood vessels that carry blood to the heart. • Ventricle – lower chambers of the heart that pumps blood. • Atriums – upper chambers of the heart that collects blood. • Left ventricle – pumps O rich blood out of the heart to the body. • Pulmonary veins – carries O rich blood from the lungs to the heart. • Septum – thin muscular wall that separates the left and right side of heart. • Aorta – largest blood vessel in the body. • Cardiovascular – combines circulatory (heart) and respiratory (lungs).

7. The Respiratory System • Respiratory System • CO2 – carbon dioxide which is removed by the lungs. • Trachea – attaches to the lungs and is also called the wind pipe. • Diaphragm – large breathing muscle attached to the lungs and separates the heart and lungs from the abdominal cavity. • Capillaries – smallest blood vessels where Oxygen is exchanged for CO2 in the lungs. • Respiratory system – main function is to supply the body with Oxygen. • Bronchial tubes – two small tubes attaching the trachea to the lungs. • Alveoli – tiny air sacs in the lungs surrounded by capillaries. • Bronchioles – small tubes within the lungs that transport air to the alveoli.

8. Genetics • What is a genotype? 2 letter code • What is phenotype? Characteristics of 2 letter code • What is incomplete dominance? 2 recessive alleles create different trait for offspring. • What is a dominant allele? One allele dominates another. • What is heterozygous? Gene pair with a dominant and recessive allele. • What is homozygous? Gene pair with 2 dominants or 2 recessives. • What is a recessive allele? The lesser of the two alleles. • How many pair of chromosomes? 23 • What is the difference between mitosis and meiosis? Meiosis is sex cell • 1 dominant plus 1 recessive = ? Dominant • Father of Genetics? Gregory Mendel • What did Mendel experiment with? Peas • What is the study of how traits are inherited? Genetics • What is the passing of traits from parent to offspring? Heredity • What is the difference between alleles and traits? Traits are the actual characteristics • What is an organism that is the offspring of many generations of the same traits? Purebred (BB) • What is an organism that has 2 different alleles for a trait? Hybrid (Bb) • What shows a person’s 23 pairs of chromosomes on one sheet? Karyotype • What is a single celled organism? Zygote • What are the 4 phases of mitosis? Prophase, metaphase, anaphase, telophase. • What phase is before mitosis? Interphase • Chromosome – an organized structure of DNA found in the nucleus that determines traits. • Genetic disorder – an abnormal condition that a person inherits through parents chromosomes. • Genetic engineering – genes from one organisms are transferred into the DNA of another organism. • Genome – all the DNA in one cell of an organism.

9. The Nervous System • Nervous System - • Brain stem – part of nervous system and controls the heartbeat and breathing by controlling the cardiac muscle and diaphragm. Also receives information from face, ears, eyes and nose. • Cerebrum – part of the brain that controls our thinking and emotions. • Neurons – nerve cell. • Brain – 3 main parts – cerebrum, cerebellum, brain stem. • Cerebellum- controls movement and balance. • Sensory nerves – the body receives information from the environment through the sensory nerves. • Axon – the long trunk part of the neuron. • Synapse – the space between neurons. • Motor nerve – carries instructions to the muscles from the spinal cord.

10. Biomes 1. What are two types of deserts? 2. Where is the alpine tundra located? 3. What are two adaptations of desert plants? 4. What are two features of savanna grassland plants? 5. What are the two seasons of the savanna grassland? 6. Which biome surrounds the grasslands and deserts and found on the coast of California? 7. What is an adaption that gives the organism a better chance to survive? 8. What are the living features of an ecosystem? 9. What are the non living features of an ecosystem? 10. What is it when an organism resembles another for survival? 11. What is an organisms evolutionary history called? 12. What are all living organisms that live in an area and the nonliving features of their environment? 13. Large geographical areas that have similar climates and ecosystems? 14.What are the 5 layers of the Tropical Rainforest? 15. Which biome is dominated by needlelike trees such as Douglas Fir and Spruce? 16. Which biome is found in New Zealand, Southern Chile, Pacific N.W. of United States and has an average yearly precipitation of 200 to 400 cm? 17. Which biome is found on the coast, has hot and dry summers and the smallest biome? 18. How much of the land on Earth do the grasslands cover? 19. What are the 3 types of wetlands? 20. What are two common trees found in the temperate deciduous forest? 21. Describe the two seasons of the taiga. 22. What is the world’s largest biome? 23. How do Savannas differ from Prairies? 24. Which biome has trees where the leaves fall off in the winter? 25. Which biome covers the south east part of the United States including Georgia? 26. Which biome has a long dry season of no rain at all and lacks trees? 27. Which biome has poor soil but is the most biologically diverse place in the world? 28. Which biome has a 9 month long winter and 6 weeks of darkness? 29. Which biome is Russian for Swampy forest and has cone bearing evergreen trees. 30. Which biome is the driest?

11. Answers 1. Hot and dry, semiarid, coastal, cold 2. Mountain tops throughout the world 3. Widely scattered, spiny, thick outer layer 4. Tap roots, large trunks, leaves drop off 5. Dry and rainy 6. Chaparral 7. Natural selection 8. biotic 9. Abiotic 10. Mimicry 11. Phylogeny 12. ecosystem. 13. biome. 14. Floor, shrub, understory, canopy, emergents. 15. Temperate Rainforest. 16. Temperate Rainforest 17. Chaparral 18. One fifth 19. Marshes, swamps, bogs 20. Oak, elm, maple, willow 21. Short summer, long winter 22. Taiga 23. Warmer, wetter and location 24. Temperate Deciduous Forest 25. Temperate Deciduous Forest 26. Grasslands 27. Tropical rainforest 28. Tundra 29. Taiga 30. desert

12. Ecology • Autotrophic – uses photosynthesis to feed itself. • Photosynthesis – sun + rain + Co2 = Oxygen and sugar energy (food) • Commensalism – one organism benefits and one not affected. • Parasitism – one benefits and one harmed • Mutualism – both organisms benefit • energy pyramid – diagram that shows the amount of energy that moves from one trophic feeding level to another. • food chain – Series of events shown in a strait line in which one organism eats another and obtains energy. • food web – Consist of many overlapping food chains in an ecosystem. • Natural Selection – a process by which individuals that are better adapted to their environment are more likely to survive and reproduce than others of the same species. • Primary producer – photosynthetic autotrophic organism that is bottom of energy pyramid. (converts sunlight into stored energy) • Primary consumer- heterotrophic herbivore that feeds on primary producers. • Secondary consumer- carnivore or omnivore that feeds on primary consumers. • Tertiary consumer – carnivore that feeds on secondary consumer. • Quaternary consumer – feeds on anything it wants. (top of food chain) • Predation – predator/prey relationship • Scavenger – heterotrophic carnivore that feeds on dead animals. • Decomposer – heterotrophic organism that feeds on feces or dead (bacteria is example) • Ecosystem – all the biotic (living) and the abiotic (nonliving) features of the environment. • Evolution – the gradual change of a trait in a species over time. • estuary – mixture of salt and fresh water. • biome - Large geographical areas that have similar climates and ecosystems. • climax community – a place where animals and plants have reached a stable stage. • Temperate Deciduous Forest - biome has trees where the leaves fall off in the winter and covers the south east part of the United States including Georgia? • Competition – when two or more organism of the same species fight over limited resources. • Tropical rain forest – most diverse biome with the greatest number of different species. • Desert – driest biome • Herbivore – organism that eats plants or primary producers. • Carnivore – organism like a wolf that eats other consumers (animals) • Omnivore – can be primary and secondary consumers (eats plants and animals) • Sun – provides the energy for producers to make food. (original source of all energy) • Habitat – where an organism lives and finds food and shelter. • Pioneer species – first organisms to move into an ecosystem. • Limiting factors – anything that decreases the population of a species.

13. Kingdom Notes Eubacteria Kingdom • Unicellular • Prokaryotic • Heterotroph or autoroph • Pathogenic (disease) • Parasitic in human body Protists Kingdom A. Most are unicellular , but some are multicellularB. Cells have a membrane around the nucleus (eukaryotic) C. Some get nutrients and energy by eating other organismsD. Some get energy from the sun, and nutrients from the water around themE. Most reproduce by splitting in twoF. Examples are paramecium, amoeba, and kelp • G. organism that can not fit into any other Kingdom. Plant Kingdom Photosynthetic • Multicellular - • Autotroph • classified into Nonvascular (no tubes) or Vascular (tubes) • Cell walls made of cellulose

14. Kingdom notes Animal Kingdome • Multicellular (lack cell walls) • Eukaryotic • Obtain food and oxygen • Homeostasis – maintaining internal conditions stable. • Reproduce (sexually) • Heterotroph – other feeder • Adapt with environment • Movement (motile) (sessile – coral) • tissue and organs Fungi Kingdom • Heterotrophs through absorption • Cell wall made of chitin • Reproduces using spores (seeds) • Eukaryotic • Moist, warm environment Archeabacteria • Unicellular • Prokaryotic • Extreme environment • Loves Salt and extreme heat

15. kingdoms • Unicellular, prokaryote, parasitic pathogen that can live in the human body and gain its food through absorption? • Multicelular, eukaryotic, photosynthetic autotrophs, with cell walls who reproduce asexually? • Multicelular, eukaryotic, with no cell walls and heterotrophic through ingestion? • Unicellular or multicellular, eukaryotic or prokaryotic that can not fit into any other kingdom. • Cell wall made of chitin. • Most diverse kingdom, oldest, most extreme?

16. Answers • Eubacteria • Plants • Animal • Protist • fungi • Archaebacteria

17. Additional Notes • Other notes (know the 5 reasons something is considered living) • Metamorphosis – egg , larva, pupa, adult • Homeostasis – The ability to maintain internal conditions despite the outside environment. • Eukaryotic – cell with a nucleus • Prokaryotic – cell without a nucleus • Redi – disproved spontaneous generation with raw meat and fly experiment. • Spontaneous generation – belief that life can come from nonliving. • Biogenisis – fact that life can only come from living organisms. • Taxonomy – study of classification. • Binomial nomenclature – two word naming system for every organism (Genus and species) • Know in order the classification system • (Kingdom, Phylum, class, order, family, genus, species) • Spontaneous generation – theory that life comes form nonliving.