Midterm exam STUDY Flashcards
- What are the 4 “Cyclic” steps to a good scientific investigation? Which “step” starts the cycle?
Observe, Investigate, Explain, Share. Observation starts the all scientific investigations by making careful observations
- How does science differ from other disciplines & ways of knowing?
Science differs from other ways of knowing by relying on absolute facts. It does not rely on luck, chance, guesses, or just observations
- How does qualitative data differ from quantitative data? Which is better & why?
Qualitative data is based off of characteristics such as sex and color. quantitative data relies on numbers and measurements. Quantitative data is usually better suited for comparison
- What is a hypothesis? How should it be stated? What are they based on?
A hypothesis is an educated guess, written as an If, then statement, which can be tested. Good hypothesizes are based off of prior knowledge
- Why is the “SHARE” part of the scientific process so important?
So others can become educated, so other can reproduce the results and verify, and it may help others
- How do Independent variables differ from Dependent variables?
An independent variable is what is changed or made different on purpose. It is why the experiment is being conducted in the first place.
A Dependent variable is the outcome, or what is changed by the Independent variable, and the result of the experiment
How are scientific theories different from everyday theories? How can they be changed?
Scientific theories are well tested explanations, proven so many times, they are considered correct. However they are not absolutely true and can change over time as the theory may be revised or replaced as new evidence is found.
- How & When can a hypothesis turn into a theory?
When a hypothesis is supported by years of evidence, has not been disproven, and accepted by the scientific community, it becomes a theory.
- What is a “Controlled” experiment?
A controlled experiment is one where only one variable is changed at a time. This reduces the chance of error
- Bacteria cells can split in half to make more bacteria. Which characteristic of life does this represent?
The ability to reproduce
- A drop of blood under a microscope looks like thousands of small, circular units. Which characteristic of life does this represent?
Made of cells
- A 7-pound baby will be a 140-pound adult. What characteristic of life does this represent?
Grow and develop
- The average person’s body temperature is around 98.6⁰F at all times in order to sustain life. What is the term for how an organism’s body can maintain the ideal conditions for life?
Homeostasis
- What is the independent variable for the experiment above?
Music
- What is the dependent variable for the experiment above?
Test grades
- What was the control group for the experiment above?
No music
- What would be a constant for the experiment above?
Teacher, students, test, how often they listened to music
- What would be an appropriate hypothesis for the experiment above?
If students listen to music, then their test scores will increase
- What would be the best conclusion for the experiment above?
Listening to techno music is the best choice to increase test scores
- How should the data from this experiment be graphed? Line Graph or Bar Graph…Explain!
The best graph would be a bar graph, reason why, because you are comparing results, not showing a relationship over time
What molecule forms the bulk of a cell membrane? What is it about these molecules that help to hold the membrane together?
The phospholipid is the molecule that makes up the bulk of the cell membrane. These molecules are special because they are both polar and non-polar. They hold each other together, but selectively allow certain elements and molecules to diffuse across them
What are the important roles or functions of the cell membrane VERSUS the cell wall?
The cell membrane allows for the passing of certain materials.
The cell wall is used for support and protection
How are active and passive transport through a membrane different? Give examples for each!
Active transport is what your cells do when they move ions against the concentration gradient and requires energy
Passive transport is when ions go from high to low concentration in order to be balanced, and this requires no energy.
What is the best definition for osmosis?
The movement of water across a cell membrane
The smell of stink bomb in the halls is an example of which form of substance transport?
Diffusion
What happens when you sprinkle salt on a slug? (Similar to drinking salt water). Explain! Tonicity???
The salt will shrivel. This is because the salt is hypertonic. The concentration of the salt will draw the water inside the slug out.
What happens once a cell reaches “equilibrium” with its surroundings?
Molecules and their concentrations will move across the membrane in both directions equally
What is the outer-most boundary of a plant cell? Animal cell?
Plant cell is the cell wall
Animal cell is the cell membrane
How are plant and animal cells similar?
Plant and animal cells are both similar because they both have a nucleus for storing genetic material
How are plant and animal cells different?
Plant cells are different because they contain cell walls, chloroplasts, and produce their own food
Animal cells do not have cell walls, and must get their energy from another source
What do all cells have in common?
All cells have a cell membrane, a cytoplasm, and genetic material
What is an example of a prokaryotic cell? Eukaryotic cell?
An example of a prokaryotic cell would be a bacteria (does not contain a nucleus)
An example of a Eukaryotic cell would be a plant or animal (contains a nucleus)
How are prokaryotic and eukaryotic cells similar?
Both prokaryotic and eukaryotic cells contain genetic material, a cytoplasm, and a cell membrane
How are prokaryotic and eukaryotic cells different?
Only eukaryotic cells contain a nucleus, prokaryotic cells have a nucleuoid region
Eukaryotic cells have membrane bound organelles, prokaryotic do not
Eukaryotic cells are the building blocks for multicellular organisms, Prokaryotic are not and exist as is.
As it relates to material transport, why must cells stay microscopic in size?
If cells got too large, they would not be able to carry out the functions necessary to do theier job.
How do the cells within a multicellular organisms differ from that of a unicellular organism?
Cells in a multicellular organism are specialized, unlike that of a unicellular organism. For example, your body has muscle cells for momement, and skin cells for protection. A muscle cell cannot do the work of a skin cells
How are organelles similar to organs in your body?
Each one has a specialized function, just like the organs in your body.
Cell Membrane
It regulates which materials enter and exit the cell
Cell Wall
It supports and protects the cell
Ribosomes
Make proteins
Chloroplast
responsible for photosynthesis
Mitochondria
energy maker, converts glucose to ATP
Nucleus
Stores genetic material
Vacuole
Stores food or excess fluid
which of the following that are made of cells? Glucose table grass water virus oxygen tree insect
o Glucose - made of elements o table – is not living * grass o water – made of elements o virus – does not meet the criteria for life o oxygen – just an element * tree *insect
Which organelles are involved in providing energy for life?
Chloroplasts and mitochondria
Why doesn’t the mass of a “closed” system terrarium change as the plants grow, (hint: VanHelmont)?
Plants do both photosynthesis and cellular respiration. In a closed system, the plant is able to both produce and use the energy it creates.
What is the difference between autotrophs and heterotrophs?
Autotroph-an organism that can make their own food
Heterotroph – an organism that cannot make its own food and must obtain energy from the foods it eats
Give several examples of autotrophs & heterotrophs!
Autotroph – plants, photosynthetic bacteria, trees
Heterotroph – animals
What chemical process takes place within a chloroplast?
Photosynthesis
What is the driving source of energy for photosynthesis? (a.k.a. original source of energy)
The sun (radiant energy)
Where does the energy go during photosynthesis?
Energy gets stored into the glucose molecule the plant produces
What key molecules (reactants) are needed for a producer to do photosynthesis?
Water, carbon dioxide, and sunlight
What are the products of photosynthesis?
Glucose, and oxygen
How does photosynthesis affect Co2 & O2 levels in the environment?
Photosynthesis reduces carbon dioxide and increases oxygen
What factors can affect the RATE (or speed) of photosynthesis? Explain!
Amount of water
Temperature
Amount of light
How do organisms access the energy from the food they eat (or make)?
Autotrophs produce it themselves
Heterotrophs must consume the food they need
Where does cellular respiration take place?
The mitochondria
Which types of cells contain mitochondria?
All Eukaryotic cells (plants and animals)
Mitochondria have been called the “powerhouse” of cells. What is the “POWER” it makes???
They make ATP, Adenosine Triphosphate
ATP is like a rechargeable battery. How is energy STORED in ATP? How is every RELEASED from ATP?
Energy is stored through the many chemical bonds it forms. It is released when those bonds are broken.
What key molecules (reactants) are needed for a cell to do cellular respiration?
Glucose and oxygen
What waste products are released at the end of cellular respiration?
Carbon dioxide and water
How does cellular respiration affect the levels of CO2 & O2 in the environment?
Cellular respiration increases carbon dioxide and decreases oxygen
What is the key product of cellular respiration?
ATP – the energy molecule all living things use to do work
How are photosynthesis & cellular respiration LINKED or related to one another?
The reactants for one, are the products of the other. It is a cycle
Starting with sunlight; what is the complete flow of energy through an ecosystem?
Sunlight → Plant (autotroph) → Chloroplast (photosyntheisis) → production of glucose and oxygen → heterotroph → uses glucose to make ATP, Carbon dioxide and water → energy of ATP is used
Show how MATTER is recycled between photosynthesis & cellular respiration!
Matter is recycled because of the flow of reactants and products. In this case you need to know the balanced equations for both photosynthesis and cellular respiration.
What is the difference between ORGANIC and inorganic compounds?
Organic compounds contain the element Carbon
What are the 4 major classes of organic compounds for life?
Carbohydrates, proteins, lipids, nucleic acids
What are the basic “monomer” building blocks to each class of macromolecules?
Carbohydrates → monosaccharide, Proteins → Amino Acids, Lipids → Glycerides (fatty acids)
Where is all the ENERGY found in an organic compound? How is that energy released?
All energy is found in the bonds of an organic compound. It is released by the breaking of the bonds
How do heterotrophs (consumers) attain energy for all life processes?
They must consume macromolecules, which are then broken down into monomers for energy.
Which class of organic macromolecules contains the MOST potential energy? How (why)?
Lipids have the most potential energy because they contain the most bonds
What is the difference between simple and complex carbohydrates? Give examples for each!
Simple carbohydates (like glucose) are single molecules and are very simple. Complex carbohydrates (like pasta, potatoes, and starches) are long chains of monomers and must broken down itno monomers for our body to use them.
What are the primary functions (or uses) for each class of macromolecules?
Carbohydrates – energy source
Proteins – grow, repair, develop muscels, skin, hair, and nails
Lipid – storage of energy
What are some good FOOD sources for each class of macromolecule?
Carbohydrates – fruits
Proteins – fish
Lipid – nuts
what ribosomes make
protein
3rd stage: chromosomes separate
Anaphase
osmosis is a form of passive _____
transport
organelle found only in plant cells
Chloroplast
Dense center portion of nucleus
Nucleolus
jellylike matrix for organelles
Cytoplasm
Material of which chromosomes are made; condenses during prophase
Chromatin
Forms vesicles; the ______ complex
Golgi
The nuclear membrane is ______ allowing materials to pass through
Permeable
Storage/transport sacks on a cell
Vacuole
Organelle which produces protein
Ribosomes
Sack filled with enzymes; breaks down foreign substances
Lysosomes
Process of cell division
Mitosis
A plant pigment that absorbs sunlight
Chlorophyll
The links between the energy that carnivores get from eating to the energy captured by photosynthesis
Food Chain
Chlorophyll absorbs every color except this
Green
A compound needed for photosynthesis
Carbon dioxide
The product of photosynthesis
Sugar
The process by which plants and some bacteria use the energy from sunlight to produce sugar
Photosynthesis
Part of the plant where photosynthesis generally occurs
Leaves
ANOTHER compound needed for photosynthesis
Water
An animal that eats plants
Herbivore
A By-product of photosynthesis
Oxygen
of molecules of oxygen produced along with one molecule sugar
Six
