7th Grade Science Standards Review

7th Grade Science Standards Review S7L1. Students will investigate the diversity of living organisms and how they can be compared scientifically. Demonstrate the process for the development of a dichotomous key. b. Classify organisms based on physical characteristics using a dichotomous key of the six kingdom system (archaebacteria, eubacteria, protists, fungi, plants, and animals).

Dichotomous Keys Dichotomous – means divided into two parts Therefore, you will always have two choices until you get to the answer.

Major Animal Groups Does it have a backbone or no backbone? It has a vertebral column or backbone and thus fits category (1a), Phylum Chordata, which sends you to couplet 2. 1a Vertebral column present Phylum Chordata 2 1b Vertebral column absent 8

2a Hair present Class Mammalia 2b Hair absent 3 It has no hair, which sends you to 3. You notice there are no feathers, you proceed to 4. 2a Hair present Class Mammalia 2b Hair absent 3 3a Feathers present Class Aves 3b Feathers absent 4

4a Fins present 5 4b Fins absent 7 It has fins, so you move to 5. There are jaws, go to 6. Jaws Fins 4a Fins present 5 4b Fins absent 7 5a Jaws present 6 5b Jaws absent Class Agnatha

Its gills are covered by an operculum (bony plate covering gills) which places the organism in Class Osteichthyes, the true bony fish. Operculum 6a Gills covered by an operculum Class Osteichthyes 6b Gills not covered by an operculum Class Chondrichtyes

Levels of classification: Domain—most general Kingdom Phylum Class Order Family Genus Species—most specific

6 Kingdoms of Life 1. Archaebacteria 2. Eubacteria 3. Protists 4. Fungi 5. Plant 6. Animal

S7L2. Students will describe the structure and function of cells, tissues, organs, and organ systems. Explain that cells take in nutrients in order to grow and divide and to make needed materials. b. Relate cell structures (cell membrane, nucleus, cytoplasm, chloroplasts, mitochondria) to basic cell functions. c. Explain that cells are organized into tissues, tissues into organs, organs into systems, and systems into organisms.

d. Explain that tissues, organs, and organ systems serve the needs cells have for oxygen, food, and waste removal. e. Explain the purpose of the major organ systems in the human body (i.e., digestion, respiration, reproduction, circulation, excretion, movement, control, and coordination, and for protection from disease).

Cell Theory All organisms are made of one or more cells. The cell is the basic unit of all living things. All cells come from existing cells.

Eukaryotic Cells 1. Organelles – tiny parts of a cell 2. Organelles Cell wall – rigid outer covering of plant cells, bacteria, fungi Cell Membrane – inside the cell wall of plants, outer covering of animal cells (1) Controls what goes in/out of cell C. Nucleus – controls the cell; dna (1) Nuclear membrane – outer covering

Cytoplasm – jelly like substance, supports organelles E. Mitochondria – energy producer F. Endoplasmic Reticulum (ER) - transport G. Ribosomes – makes proteins H. Golgi Bodies - packages I. Chloroplasts – plants – food maker

Vacuoles – storage container for food, water and waste K. Lysosomes – cleanup crew - animals 3. Prokaryotes – no nucleus - bacteria 4. Eukaryotes – cells with a nucleus

Cell—basic unit of life Tissue—Groups of cells working together Organ—groups of tissues working together Organ System—Groups of organs working together Organism—all of the organ systems working together

(Ingredients) (Results) 6CO2 + 6H2O + sunlight  C6H12O6 + 6O2 Plant cells have to make their own food before the mitochondria can break it down for energy (ATP). Plants make food in the chloroplast through a process known as photosynthesis. (Ingredients) (Results) 6CO2 + 6H2O + sunlight  C6H12O6 + 6O2 Carbon Water Glucose Oxygen Dioxide (food)

Major Systems: Digestive Integumentary Respiratory Excretory/Urinary Reproductive Endocrine Circulatory/Cardiovascular Nervous Muscular Immune Skeletal

Digestive System Respiratory System Breaks down food into molecules Molecules are absorbed into blood and carried throughout the body Respiratory System How our bodies get and use oxygen and release carbon dioxide and water Two parts Breathing Cellular respiration (energy release from food)

Reproduction System Circulatory System System responsible for human reproduction (having babies) Circulatory System Transport oxygen and carbon dioxide Distribute nutrients Transport wastes Distribute hormones Regulate body temperature

Nervous System Skeletal System Two main functions: Gather and interpret information Respond to that information as needed Responsible for Coordination and control Skeletal System Composed of bones, cartilage, and the connective tissue that holds bones together Primary Function: Support and protect the body and allow movement

Muscular System Immune System 1. Is made of muscles 2. Allows movement and flexibility Immune System 1. Fights pathogens (fights disease) 2. Is a team of individual cells, tissues, and organs that work together to keep you healthy

S7L3. Students will recognize how biological traits are passed on to successive generations. Explain the role of genes and chromosomes in the process of inheriting a specific trait. b. Compare and contrast that organisms reproduce asexually and sexually (bacteria, protists, fungi, plants & animals). c. Recognize that selective breeding can produce plants or animals with desired traits.

Genes - pieces of chemical information found on chromosomes that carry instructions for making all the proteins that a cell needs. B. Most genes are either dominant or recessive C. Dominant trait is the trait you can see TT (capital letters); Tt D. Recessive trait is seen if dominant one isn’t present tt (lower case)

Incomplete Dominance - neither gene is dominant or recessive. (a “blending”) (1) Example - White flower (WW) crossed with red flower (RR). Co-dominance – both genes show up; they dominate together Ex: black chicken (BB) crossed with White chicken (WW). (a) babies with both black and white feathers (a) pink

Phenotypes and Genotypes Phenotype vs. Genotype A. Phenotype is what you see when you look at an organism B. Genotype is the actual gene combination an organism has Example Phenotypes and Genotypes Tall TT Tt Short tt

Homozygous vs. Heterozygous A. Homo-means same B. Homozygous—Alleles are the same—can be either dominant or recessive example TT or tt C. Hetero-means different D. Heterozygous—Alleles are different example Tt

Punnett Square review Write down what you know (parent genotypes, which trait is dominant, etc.) Draw box Put one parent on top one on the side Drop and slide

Problem 1. In seals, long whiskers (W) are dominant and short whiskers (w) are recessive. The parent genes are WW and Ww. Find genotype, phenotype and probability for offspring. Problem 2. In seals, long whiskers (W) are dominant and short whiskers (w) are recessive. The parent genes are Ww and Ww. Find genotype, phenotype and probability for offspring

Problem 3. In purple people eaters, horns are dominant and no horns are recessive. Parent gene codes are Hh and hh. Find genotype, phenotype and probability.

Organisms reproduce one of two ways: Asexually (one parent) Offspring is genetically identical to parent Sexually (two parents) Offspring is genetically different to parent Selective breeding can produce plants or animals with desired traits.

Kingdom Archeabacteria Eubacteria Protists Fungi Plants Animals Cell Type (eukaryotic or prokaryotic) Food (autotrophic or heterotrophic) Number of Cells (unicellular or multicellular) Where do they live? How do they reproduce? Archeabacteria Prokaryotic Either Unicellular Hostile environments Asexual- binary fission Sexual-conjugation Eubacteria Everywhere Protists Eukaryotic Water and Moist surroundings Fungi Heterotrophic multicellular; Except yeast-unicellular Land and water Plants Autotrophic Multicellular Sexually Animals

S7L4. Students will examine the dependence of organisms on one another and their environments. Demonstrate in a food web that matter is transferred from one organism to another and can recycle between organisms and their environments. b. Explain in a food web that sunlight is the source of energy and that this energy moves from organism to organism. c. Recognize that changes in environmental conditions can affect the survival of both individuals and entire species.

d. Categorize relationships between organisms that are competitive or mutually beneficial. e. Describe the characteristics of Earth’s major terrestrial biomes (i.e. tropical rain forest, savannah, temperate, desert, taiga, tundra, and mountain) and aquatic communities (i.e. freshwater, estuaries, and marine).

Energy for a food chain comes from the sun! A close relationship between two organisms is known as symbiosis. There are three types of symbiosis. 1. Mutualism—both organisms benefit Commensalism—one organism benefits while the other is unaffected 3. Parasitism—one organism benefits while the other organism is harmed

Biome—group of ecosystems with similar climates 6 land 2 water Rain Forest (tropical or temperate)—rainy Desert—very dry Grassland (Savanna, Prairie) Deciduous Forest—4 seasons Taiga (Boreal or Coniferous forest) Tundra—frozen soil (permafrost) Freshwater—lakes, rivers, streams Marine—brackish and salt water

S7L5. Students will examine the evolution of living organisms through inherited characteristics that promote survival of organisms and the survival of successive generations of their offspring. Explain that physical characteristics of organisms have changed over successive generations (e.g. Darwin’s finches and peppered moths of Manchester). b. Describe ways in which species on earth have evolved due to natural selection. Trace evidence that the fossil record found in sedimentary rock provides evidence for the long history of changing life forms.

Adaptation—characteristic that helps an organism survive and reproduce A. Physical (ex. Long neck, striped fur) B. Behavioral Evidence of Change over time A. Fossils—trace or remains of an organism that lived long ago 1. Most often found in sedimentary rock B. Fossil Records—using fossils to make a timeline of life on earth

Charles Darwin First to explain how evolution happens Known as the “Father of Evolution” Evolution happens through Natural Selection 1. Process where organisms better adapted to their environments are more likely to survive and reproduce Some genes make an organism more likely to survive to reproduce