Midterm Review Flashcards
In an experiment, the variable that changes is called…
Independent
The setup or group that does not receive the experimental treatment is called the…
control group
What is a hypothesis?
a possible explanation to the scientific question
Maintaining stable internal conditions is called what?
homeostasis
The variable that is measured in a experiment (the data)
dependent
True or False: A hypothesis can be disproven or supported but is never said to be proven or “fact”.
true
How many independent variables are in a controlled experiment?
one
Something that a living thing responds to is called what?
a stimulus
What is a neutral pH?
7
If an acid is added to a neutral solution, how does the pH change?
it will become more acidic (1-6)
What does DNA stand for?
deoxyribonucleic acid
What does RNA stand for?
ribonucleic acid
How much energy moves up from one trophic level to another in a food chain?
10%, the rest is lost as heat. This is also true of biomass, it decreases by a factor of 10 as it goes up each level. 100 grams of grass can only support 10g of primary consumers.
What is an ecological community?
All individuals of all living species in a given area.
Does energy cycle or move straight through an ecosystem?
move through
Do nutrients cycle or move straight through an ecosystem?
cycle
What is primary productivity?
The amount of biomass of producers. Depends on abiotic factors such as water, sun, nutrients etc.
What is a primary consumer?
organism that eats producers
What is a secondary consumer?
organism that eats primary consumers
What is chemosynthesis?
process by which bacteria make glucose from hydrogen sulfide instead of photosynthesis.
What is photosynthesis?
The process of using water and carbon dioxide plus energy from the sun to create glucose and oxygen.
What is the carbon cycle?
a series of processes by which carbon compounds are converted in the environment, involving the incorporation of carbon dioxide into living tissue by photosynthesis and its return to the atmosphere through respiration, the decay of dead organisms (decomposition), storage as calcium carbonate (shells) and the burning of fossil fuels.
What is the nitrogen cycle?
The nitrogen cycle is a repeating cycle of processes during which nitrogen moves through both living and non-living things: the atmosphere, soil, water, plants, animals and bacteria. In order to move through the different parts of the cycle, nitrogen must change forms. Ammonia, ammonium and Nitrogen are all compounds involved
What is the monomer of a protein?
amino acid
What is the monomer of a carbohydrate?
glucose (monosaccharide)
What is the monomer of a nucleic acid such as DNA, RNA and ATP?
a nucleotide (sugar, phosphate groups and a nitrogenous base)
Give three types of polysaccharides
Starch, Cellulose and Glycogen
How are polysaccharides made?
Dehydration synthesis- bonds together monomers into a polymer. This process creates water
How are polysaccharides broken apart?
Hydrolysis- breaks apart the polymer into its monomers using water.
What is the C, H, O ratio of carbohydrates?
1:2:1
What is iodine an indicator for?
polysaccharides
What is Benedict’s solution an indicator for?
glucose/monosaccharides
Which element is all life based on?
Carbon
What type of macromolecule are enzymes?
proteins
Waxes, steroid hormones and oils are what type of macromolecule?
Lipids
What molecule is the cell membrane made of?
phospholipid bilayer
What are the three parts of a nucleotide?
Sugar, phosphate and nitrogenous base
Lipids are made of which elements?
C,H and O but in a different ratio than carbohydrates
Saturated fats have how many double bonds?
none
True or False: Enzymes can be reused over and over
true
What does the smooth ER do?
makes lipids
What is the function of ribosomes?
build proteins
A chain of amino acids is folded into what molecule?
protein
What organelle is responsible for removing wastes in the cell?
lysosome
What does the mitochondria do and what cells are likely to have a lot of them?
Create ATP energy for the cell. Most likely in cells such as muscles that need a lot of energy
What does the rough endoplasmic reticulum (RER) do?
Packages proteins and sends them to the golgi apparatus
What does the Golgi apparatus do?
Receives and then sends out molecules to where they need to go. Sometimes this means out of the cell.
What is the function of the nucleus?
To store and protect DNA
In what type of cells will there be a nucleus?
Eukaryotic
Do bacteria have a nucleus?
no
What organelles do plants have that animal cells do not?
cell wall, chloroplast, large central vacuole
What does a vacuole do for plants?
Stores water and other chemical compounds. Gives the cell pressure to help the plant to remain upright.
What do contractile vacuoles do for animal cells?
Allow them to remove excess water and maintain osmotic balance.
What organelle do animal cells have that plants do not?
centrioles
What does the nucleolus do?
makes ribosomes and is located inside the nucleus
What are the 3 parts of cell theory?
All living things are made of cells
All cells come from existing cells
Cells are the basic unit of structure and function of living things
Endosymbiotic theory states that mitochondria and chloroplasts came from existing single celled organisms. What is the evidence for this?
Both of these organelles have their own DNA, a double membrane and reproduce on their own.
What are prokaryotes?
single celled organisms with no nucleus. Bacteria and Archaea
What is osmosis?
diffusion of water from high to low concentration across a semi permeable membrane.
If the inside of a cell contains 70% salt and the outside contains 40% salt. Which direction will the water move?
It will move into the cell because water moves from high concentration outside the cell, into the cell. Also remember “Salt Sucks” so water moves toward higher salt concentration
Passive movement of molecules such as oxygen and carbon dioxide from high to low concentration across a cell membrane is called what?
diffusion
Passive movement of larger molecules such as glucose across a cell membrane that requires a protein channel is called what?
facilitated diffusion
Active transport that requires movement or a pump in the cell wall requires what?
energy in the form of ATP
True or False: When equilibrium is reached, the molecules stop moving
false; they will continue to bounce back and forth across the membrane but net movement is zero because both sides have roughly the same concentration.
A hypertonic solution is what?
a solution with higher solute (salt, sugar) than the cell
A hypotonic solution is what?
a solution with lower solute concentration than the cell
An isotonic solution is what?
A solution with the same concentration as the cell.
What are the reactants of photosynthesis?
carbon dioxide, water and sunlight
What are the products of photosynthesis?
oxygen and glucose
What are the reactants of cellular respiration?
oxygen and glucose
What are the products of cellular respiration?
carbon dioxide and energy (ATP)
What does aerobic mean?
with oxygen
What does anaerobic mean?
without oxygen
After glycolysis, what happens if the cell does not have oxygen?
fermentation
What 3 parts does ATP have?
sugar, 3 phosphate groups and a base
What happens to ATP to release energy?
It loses a phosphate group
Which colors of light are best absorbed by plants?
Red and Blue
Which color of light the least absorbed by plants?
green
What is a heterotroph?
Means “other feeder”, an organism that needs to eat another organism to survive.
What is an invasive species?
A species that comes from another place AND causes harm to the native ecosystem
