Living Environment Regents Exam Review - Unit 1

Unit 1 Review

nutrition

• autotroph = producer

• heterotroph = consumer

• take in and change organic compounds into usable form (can cross the cell membrane)

• organ systems in humans: digestive system

• cell structures: lysosome, vacuole

transport

• distribute materials around the body of an organism

• organ systems in humans: circulatory system

• cell structures: E.R., cytoplasm

excretion

• remove cell (metabolic)

• wastes from the organism

• organ systems in humans: urinary (excretory) system

• cell structures: cell membrane, vacuole

regulation

• control and coordinate the organism’s life processes as it responds to internal/external changes

• organ systems in humans: nervous system, endocrine system

• cell structures: nucleus

reproduction

• make more of the same species

• sexual and asexual

• organ systems in humans: reproductive system

• cell structures: nucleus (centrioles)

respiration

• process used by the cell to make energy (ATP)

• WHAT ALL LIVING THINGS MUST DO TO STAY ALIVE!!

• organ systems in humans: requires oxygen from the respiratory system

• cell structures: mitochondria

gas exchange

• exchange of oxygen and carbon dioxide

• organ systems in humans: respiratory system

• cell structures: cell membrane

growth

• increase the size and/or number of cells

synthesis

• to build large, complex molecules from small, simple molecules

• ex. protein synthesis: many amino acids turn into protein

• cell structures: ribosomes (protein synthesis)

metabolism

• the sum total of all of the chemical reactions (life activities) occurring in an organism

• also known as metabolic activities (what keeps and organism alive)

• metabolic activities include such processes as photosynthesis, cell respiration, active transport, protein synthesis, and chemical digestion

• most metabolic activities require ENERGY from ATP

homeostasis

• maintaining a constant internal environment; internal balance; dynamic equilibrium

• failure to maintain homeostasis = disease/death

• feedback mechanisms have evolved to help the organism maintain balance

  • Example: increase breathing and heart rates during exercise

  • Example: controlling blood sugar levels with insulin and glucagon from the pancreas

  • Example: regulating gas exchange and water loss in a plant by opening and closing stomates

steps in the scientific method

1. state the problem - in the form of a question

2. make a hypothesis (prediction) - always a statement

3. design a controlled experiment

4. collect and analyze the data

5. make a conclusion

6. report the results and repeat the experiment

1. state the problem

• always in the form of a question

• usually involves making observations and conducting some background research

• thorough research prior to identifying the problem prevents repeating previous experiments and helps the scientist design an appropriate experiment to investigate the problem

2. make a hypothesis (prediction)

• always a statement

• it’s useful to write your prediction in the form of an IF…THEN… statement

• Example: INDEPENDENT VARIABLE, dependent variable

  • IF BEAN PLANTS ARE GIVEN MIRACLE GRO EVERY DAY FOR ONE WEEK, then the height of the plants will increase.

independent variable

• the factor, or condition, being tested

• the thing that changes (changin’)

• when making a graph, the independent variable goes on the x-axis

dependent variable

• the factor, or condition, being measured

• data

• when making a graph, the dependent variable goes on the y-axis

3. design a controlled experiment

• must include the following:

  • at least one experiment group (the group contains the independent variable; there can only be ONE independent variable)

  • a control group (this is the group that DOES NOT change - it is used as a comparison against the results of the experimental group)

  • a statement of the dependent variable (what do you intended to measure and/or observe)

  • a large sample size (BIGGER IS ALWAYS BETTER - makes for a more valid conclusion from the data analysis)

  • # trials (increasing the number of trials is a way to increase the amount of date if there is a small sample size)

  • a data table to organize the information gathered in the experiment

  • a number of constants (conditions or factors that are the SAME in both the experimental and control groups - THE MORE CONSTANTS = MORE VALID CONCLUSION)

4. collect and analyze the data

• usually involves making a graph of the data to visually represent the relationship between the independent variable and the dependent variable

5. make a conclusion

• examine the data and determine what the results are

6. report the results and repeat the experiment

• in order for a conclusion to be considered valid (useful) the experiment must be repeated by other researchers with the same conclusion