TAKS Science EXIT Review

Living Systems and the Environment

Organization of Organisms

• Cell

• Tissue

• Organ

• System

• Organism

Give examples of each type.

SystemsCirculatory Respiratory Digestive Muscular Skeletal Nervous

Circulatory Heart

Respiratory

Digestive Stomach

MuscularMuscles

move bones

SkeletalRibs protect

the lungs

NervousSpinal Cord

Complete each blank with an example of how each system works with another. Diagonally, give an example of an organ of each system.

TAKS Questions

TAKS Questions

Cells

• A cell is the smallest part of any living thing. 

• There are many parts of a cell.  

• Each part of a cell completes a certain function for the cell.

Plants vs. AnimalsSome differences between Plant cells and Animal cells are: • Plant cells have cell walls as their outermost layer • Plant cells have chloroplasts that contain chlorophyll for

pigmentation and photosynthesis• Plant cells have larger vacuoles (used for storage) • Some Animal cells have flagellum connected to the cell

membrane which aids in movement of the cell

Parts of a Cell

• Cell Membrane - forms the outer boundary of the cell and allows only certain materials to move into or out of the cell

• Cytoplasm - a gel-like material inside the cell;  it contains water and nutrients for the cell

• Nucleus - directs the activity of a cell; it contains chromosomes with the DNA

• Mitochondria - break down food and release energy to the cell

• Vacuoles - are storage areas for the cell

Ecosystems

• Producers

• Primary consumers

• Secondary consumers

• Decomposers

• Ecological Succession

Ecological Succession•Succession – a series of predictable changes that occur in a community over time

•Primary Succession – changes that occur in an area where no ecosystem previously existed

•Secondary Succession – changes that occur after an existing ecosystem has been disturbed

Species and Adaptations

• Species – a group of similar organisms that can mate and produce fertile offspring

• Adaptations – a genetic trait that helps an organism survive and reproduce

• Evolution – a change in a species over time• Natural Selection – a process by which

individuals better adapted to their environment are more likely to survive and reproduce

Symbiosis

• Mutualism - both species benefit

• Commensalism - one species benefits, the other is unaffected

• Parasitism - one species benefits, the other is harmed

• Competition - neither species benefits

• Neutralism - both species are unaffected

Predator - Prey• A predator is carnivorous. This means that it lives by

eating other animals, which are known as it's prey. The term predator usually refers to animals that catch and kill. Most predators are larger that their prey; they have special adaptations to help them find and catch their food. These include good vision, a keen sense of smell, or strong legs for rapid movement.

• Prey also have special adaptations to help them survive the attack of their predators.

• Camouflage helps them blend in with their environment and hide, sharp senses warn them of attack, and speed allows them to escape.

Food Webs & Food Chains

• Food chains and webs show how food and energy are passed between species.

• Pay attention to the direction of the arrows.• Producers, Primary Consumers, Secondary Consumers,

Decomposers• Predator/Prey

Genetics• Gregor Mendel is known as the father of genetics. He used pea plants to

study how traits are passed from one generation to the next.

Dominant Allele= A trait that prevents the showing of other traits. It is a gene that is fully expressed when two different alleles are present.

Recessive Allele= A trait that is hidden by a dominant trait. It is a gene that is not expressed when paired with a dominant allele.

Incomplete Dominance= Neither trait is dominant or recessive.

Phenotype= How your features look.

Genotype= What your chromosomes say your features are.

Heterozygous= Having two different alleles for a trait.

Homozygous= Having two of the same alleles for a trait.

Punnett Square

• Monohybrid crosses look at one set of alleles.

  T t

T    

T    

T T x T t

Homozygous Dominant crosses with

Heterozygous

Homozygous Recessive crosses with

Heterozygous

t t x T t

  T t

t    

t    

Remember Me?

• Photosynthesis – carbon dioxide, water, and energy from sunlight produce food and oxygen in plants. The food is _____ by the plant and the _____ is released.

Chemical reaction is:

Remember me too?

• Respiration – a process in organisms that uses the oxygen they breathe to release energy from glucose. and water are also produced. It mostly occurs in the mitochondria of cells.