Cells and cellular processes
1. All cells come from preexisting cells
2. Cells are the basic structural and functional building blocks of life.
3. All living things are composed of cells.
What level of organization comes after cells? (hint: what do cells make up?)
Tissues; multiple of the same type of cell combine to make up one type of tissue.
What structure inside cells contains genes?
DNA, chromosomes
Natural selection
What term describes a collection of living (biotic) and nonliving (abiotic) components interacting in an area?
Ecosystem
Which cell structure controls what enters and leaves the cell?
A group of tissues working together forms what? Provide an example.
In Mendelian genetics, what do we call different versions of the same gene?
Alleles (different versions of a sequence of DNA, represented using a single letter, eg. blue eyes may be represented by 'b' while brown eyes may be represented by 'B')
What do fossils provide evidence of?
Past life and how species have changed over time. Using principle of superposition and other principles scientists can determine the order in which changes occurred.
What type of organism makes its own food using sunlight?
Producer (plants via photosynthesis)
Which organelle in plant cells captures sunlight to make food via photosynthesis?
Chloroplast
Which body system transports oxygen and nutrients throughout the body?
Circulatory system (via veins and arteries).
Why does sexual reproduction produce more genetic variation than asexual reproduction?
If a resistance trait in a population of insects increases in frequency in the population over multiple generations, which process is occurring?
Evolution through natural selection (the distribution of traits in the population is changing over time = evolution).
Why are decomposers important in ecosystems?
They break down dead organisms and return the atoms from the organisms and nutrients to the soil to be reused (cycling matter).
During cell division (mitosis), what must happen to the DNA before the cell splits?
The DNA (instructions) must replicate (be copied) so that each daughter cell gets an identical copy and can continue functioning.
Why must body systems work together to maintain homeostasis?
They require multiple systems to regulate internal conditions like temperature and oxygen. (eg. circulatory system works with lungs to pick up oxygen and then deliver it to the other organs, heart, muscles, brain etc.)
What type of genetic change occurs when DNA is altered and what is the result?
Mutation; increased genetic variation. The mutation could result in the same trait, a new trait that is beneficial, or a new trait that is harmful,
Why can individual animals not evolve?
Evolution refers to changes in the number of individuals with a trait (frequency of a trait) in a population over time (generations). An individual cannot evolve because an individual animal is not a population of animals.
What happens to energy as it moves through a food chain?
About 10% of energy is transferred to the next level, 90% of energy is "lost" (NOT DELETED) --- sent to thermal energy through metabolic processes, respiration, and waste.
Mitochondria perform which chemical reaction? Write the chemical equation for the reaction.
Cellular respiration (releasing energy from food (sugars) for the cell to use). Sugars (glucose, C6H12O6) + 6O2 --> 6CO2 + 6H2O and ATP
During exercise, how do the respiratory and circulatory systems work together?
The respiratory system brings in oxygen and the circulatory system transports it to cells in different organs.
How can biotechnology be used in medicine or agriculture?
Scientists can modify genes to produce useful traits (such as disease resistance in crops or medicines (making bacteria produce insulin), or directly changing diseased versions of a gene to the healthy allele (gene therapy)).
Selective breeding/artificial selection
Genetic engineering/modification
Gene therapy
Cloning
Why is biodiversity important for the stability of ecosystems?
Biodiversity = genetic variation. Different traits in the population gives the species to have a chance that some individuals will survive changes and reproduce because they may be more adapted to the environment.
How can human activities such as deforestation affect ecosystems?
They can destroy habitats and disrupt food webs and populations.