Investigations are conducted to
Identify potential problems and to create solutions to those problems before they actually occur
An explanation formulated to answer the questions being investigated; A statement that can be tested
Steps of Forming a Hypothesis
1. Identify the problem-Observe and determine the problem to be investigated
2. Ask questions-Ask questions and attempt to formulate a solution to the problem
3. Formulate a Hypothesis-Formulate explanations to answer the questions. This involves making predictions that follow from the initial statement of the problem. Is not subject to interpretation.
If no reasonable test can be designed..
it becomes necessary to reformulate the hypothesis. It is of little value to quantitatively pursue the validity of a statement without any ability to measure an outcome.
1. Problem identification
2. Question asking
3. Hypothesis development
4. Data collection and experimentation
Collect data throughout the scientific process to test the hypotheses or predictions in a controlled environment.
Scientists use the 5 senses to learn as much as possible during data collection.
Direct-such as listening to a bird call
Indirect-such as observing qualities of planets
Data typically cannot be collected from every member of a population. Collect information from a representative sample of the population. Obtain data from a subset of the population that looks like the population, but is small and more manageable.
Involves comparing a control group and an experimental group. Both groups are compared to understand what effect the variable has on the experimental group.
Must analyze data collected during experimentation. The researchers must determine if the data is reliable (consistent with past results) and whether or not it supports the hypothesis.
Broad statement of what is thought to be true; A theory that is thought to be true may be proven incorrect when technology enables better data collection
Mathematics in Science Research
Data is recorded in numerical form.
Data are then related to one another through the relationships established by graphs and empirical formulas.
No modern conveniences could exist without math because the creation of all technology is ultimately mathematical.
If mathematics was not used..
the best scientific descriptions would be purely qualitative in nature.
As improvements are made, collection of new data often leads to more refined alternative explanations
Measuring and observational devices have been developed so that smaller increments of time and length have become accessible
A method whereby conclusions follow from general principles; Leads to a specific conclusion; General to Specific
A method of arriving at general principles from specific facts; Specific to General
Two or more tissue types work together to perform a specific function; Possible to perform extremely complex functions
Hierarchy of the Structure of the Human Body
Bottom to Top:
One layer of cells. Is found in body structures where absorption, secretion, and filtration occur.
Found throughout the body; It serves to connect different structures of the body; Has its own blood supply
Involuntary control; Found in the walls of hollow organs, such as intestines, blood vessels, bladder, and uterus
also called the Cardiovascular System
Consists of the heart, blood vessels, and blood
Supports the circulation and distribution of various substances throughout the body
Oxygen, hormones, and nutrients from food are some of these substances
Consists of all the organs from the mouth to the anus involved in ingestion and breakdown of food
Organs include the esophagus, stomach, small and large intestines, rectum, and anus
Makes enzymes that break down food
Any food that is not digested is expelled through the anus
Absorption of nutrients occurs in the small intestine
Also called the excretory system
Helps maintain the water and electrolyte balance, regulates the acid-base balance of the blood, and removes all nitrogen-containing wastes from the body
Helps regulate blood volume and pressure by adjusting urine volume
Activates vitamin D
Controls the blood pressure, heart rate, and distribution of blood
Consists of the brain, spinal cord, and nerves
Serves as body's control system
Consists of the skin, mucous membranes, hair, and nails
Also serves as a barrier to pathogens
Consists of lymph nodes, lymph vessels that carry lymph, the spleen, the thymus, and tonsils
Supports the immune system
Transports sex hormones
Consists of skeletal muscles, tendons that connect muscles to bones, and ligaments that attach bones together to form joints
Cardiac and Smooth muscles are not included here
Main purpose is to produce offspring
Consists of the testes, penis, ovaries, vagina, and breasts
Keep's the body's cells supplied with oxygen and removes carbon dioxide as it is released from cells
Consists of the nasal cavity, pharynx, larynx, trachea, bronchi, and lungs
Provides for air exchange and supplies tissues with oxygenated blood
Through these walls, the oxygen and carbon dioxide move in and out of the lungs via small blood vessels called arterioles
Provides support and protection for the body and its organs
Consists of bones, cartilage, ligaments, and joints
Storage for minerals such as calcium and phosphorus
Body facing forward, feet are parallel to each other, arms are at he sides with the palms facing forward
Cut made along a horizontal plane to divide the body into upper and lower regions
Cut made along a longitudinal plane that divides the body into front and back regions
Receive, interpret, and respond to internal and external stimuli via the nervous system
Allow voluntary and involuntary movement of body via the musculoskeletal and neurological systems
When all the needs of the body are met and all of the organ systems are working properly
This system works as the transportation system for substances such as oxygen, carbon dioxide, and nutrients in the body
This system breaks down food so that the nutrients can be easily passed into the blood and circulated throughout the body
This system protects internal tissues from injury, waterproofs the body, and helps regulate body temperature, This system also serves as a barrier to foreign substances
This system helps cleanse the blood and houses the white blood cells that are involved in protecting the body from environmental pathogens
This system acts as the body's control system and is necessary to protect the body from changes in the internal and external environment
This system keeps all the cells in the body supplied with oxygen and removes the carbon dioxide
This system provides support and protection for the body, supplies a framework used to create movement, and serves as storage for minerals, such as calcium
This system helps maintain the water and electrolyte balance within the body, regulates the acid-base balance in the blood, and removes all nitrogen-containing wastes from the body
Tiny blood vessels that transport blood from arteries to veins within the body
Serve as the location for the exchange of oxygen, carbon dioxide, fluid, and nutrients within the body
Flow of Blood through the Heart
Deoxygenated blood enters into the heart through the superior and inferior vena cava
Blood travels into the right atrium and flows through the tricuspid valve into the right ventricle
Blood is pushed through the pulmonary valve into the pulmonary artery and lungs when the right ventrical contracts and picks up oxygen
Oxygenated blood is then carried back to the heart by the pulmonary veins into the left atrium through the mitral valve and into the left ventricle
Contraction of the left ventricle forces the blood through the aortic valve, through the aorta, and out to the entire body
Q: If the mitral valve is damaged, which problem may occur?
A: Backflow of blood into the left atrium
The mitral valve is on the left side of the heart, separating the ventricle and atrium
True or False: Blood that passes through the tricuspid valve enters the left ventricle
False. Blood that passes through the tricuspid valve enters the right ventricle
True or False: Blood that passes through the mitral valve enters the pulmonary artery
False. Blood that passes through the mitral valve enters the left ventricle
True or False: The pulmonary valve ensures that blood stays in the aorta
False. The pulmonary valve ensures that blood stays in the pulmonary artery
Act of taking in oxygenated air
When abdominal muscle contracts, pulls air into the lungs
Chest cavity enlarges, creating negative pressure in the chest cavity and pulls air into the lungs
It is through the walls of the _____ that oxygen and carbon dioxide move in and out of the capillaries in the lungs
Peripheral Nervous System
Cranial and spinal nerves that extend beyond the CNS
Divided into the automatic nervous system and the sensory-somatic nervous system
Autonomic Nervous System
Controls automatic body functions, like heartbeat and digestion
Includes both the sympathetic and parasympathetic nerves
Sensory-Somatic Nervous System
Consists of 12 pairs of cranial nerves and 31 pairs of spinal nerves and associated ganglia
Controls voluntary actions like talking and walkin
Receive stimuli from the internal and external environment and bring those stimuli to the neurons for interpretation
Three Main Functions of the Nervous System
Provide sensory, motor and integrative functions within the body
True or False: The nervous system supplies the body with oxygen and removes carbon dioxide
False.This is a function of the respiratory system
True or False: The nervous system releases heat built up by the muscular system
False. This is a function of the integumentary system
Rhythmic contractions that propel food towards the colon and anus
Move food along the gastrointestinal tract as the food is mechanically and chemically broken down
The surface area for absorption in the small intestine is increased as a result of
Villi and microvilli.
Villi and Mircovilli
Finger-like projections of tissue in the intestines that significantly increase the surface area from which nutrients are absorbed
Process of white blood cells squeezing through capillary slits in response to cytokines
An individual does not produce his or her own antibodies, but rather receives them directly from another source, such as mother to infant through breast milk
An individual receives a vaccine that stimulates an actual infection by a pathogen, stimulating the body to produce antibodies for future protection
What is released by damaged cells in an effort to draw white blood cells to the area of damage?
What is the physiological benefit of a mild to moderate fever?
The warm body temperature that occurs, accelerates the destruction of pathogens and increases the activity of white blood cells
Average number of children a woman will have during her childbearing years which occur between the ages of 15 and 44
Factors that affect birth and fertility rates
Religion, culture, economy, employment, government, education, literacy, infant mortality rates, abortions, and accessibility of family planning
Fertility rates are higher in which types of countries?
Fertility rates are higher in less-developed countries due to higher infant and child mortality rates
Act of an individual moving out of one region or country to live in another (migrate out)
Changes in a Population are affected by the country's
Economy, politics, medical care, natural resources, food, land, water, and climate
Biological Classification System
Developed by biologists to name, organize, and categorize organisms
Occurs when some individuals of a species are better able to survive in their environment and reproduce than others
"Survival of the Fittest"
Changes in the DNA that affect the way a gene functions
Permanent changes in DNA sequences
Some individuals of a species are better able to survive and adapt to the environment in which they live
Nucleic Acid Structure
Chain of nucleotides that consists of a pentose, a phosphate group, and a nitrogenous base
Cells copy the instructions in the DNA into RNA and send the messenger RNA to the ribosomes
Contains digestive enzymes that are capable of disposing of cellular debris and worn cellular parts
Microtubule-organizing centers that help to form and organize the mitotic spindle during mitosis
Control center of the entire cell because it contains the cell's genetic material and directs all of the activities of the cell
Produces a more specialized cell from a less specialized cell
Determines what cell type each cell will become
Process of cell duplication in which two daughter cells receive exactly the same nuclear material as the original cell
Occurs to replace old and dying cells with genetically identical ones
Process carried out by green plants, green algae, and certain bacteria
Energy from sunlight is trapped and used for synthesis of glucose
When the dominant and recessive genotypes interact to produce an intermediate phenotype
Mixture of two traits
Bands of Wavelengths from Short to Long
Gamma ray, Xray, Ultraviolet, Visible, Infrared, Microwave, and Radio waves
Conservation of Energy
Total constant energy is maintained by the conversion of energy between kinetic and potential
Law of Conservation of Energy
Energy is not lost but rather transferred back and forth between kinetic energy and potential energy
Negatively charged subatomic particles found in various energy levels (orbital shells) around the nucleus
Control the rate of chemical reactions
Increase reaction rates by lowering activation energy
Ionization Energy or Ionization Potential
Energy required to completely remove an electrom from a gaseous atom or ion
Column in the Periodic Table
Displays elements that are similar in their chemical properties due to having a similar arrangement of outer shell electrons
Act as catalysts for special chemical reactions within the human body
Catalyze both forward and reverse reactions so equilibrium is maintained
Measure of hydrogen ion concentration within a solution
Measure the strength of acidic solutions and the strength of basic solutions
Q: Suppose the activit of hydrogen ions in a solution is 1 part per ten thousand. Find the pH value of the solution. Is this a basic or acidic solution?
A: pH=4; acid
Q: What does a difference of one unit on the pH scale below represent?
A: A concentration difference of 10
Have one or more double or triple bonds between carbon atoms
One double bond-Alkenes
Elements that may accept or donate electrons readily and possess a mixture of metallic and nonmetallic properties
Lewis Structures or Lewis dot diagrams
Provide visual representations of covalent bonding between atoms of a molecule
Atoms are shown and surrounded by dots that represent each of the valence shell electrons
Why do two hydrogen atoms need to be connected together in the natural state?
Hydrogen exists only in pairs because the atom is unstable on its own. A covalent bond is necessary to make the atom stable
On the left side of the reaction sign (→); Are substances consumed or altered in the chemical reaction
Located on the right of the reaction sign (→); Substances formed as the results of a chemical reaction
Balancing Chemical Equations
Make certain that there are equal numbers of each atom on the reactant side and the product side
*Since adding the 2 to N, it also multiplies the I..so it's still not balanced
The energy required to raise one unit of mass of a substance by 1deg C; Enables water to undergo minor temperature changes compared to the environment
High Heat of Vaporization
The amount of heat necessary to cause a phase transition between a liquid and a gas; Large a mount of heat is needed to vaporize liquid
Gas Diffusion and Molecular Mass Formula
R1/R2 = square root (M2/M1)
R1 = rate of effusion of gas 1
R2 = rate of effusion of gas 2
M2 = molecular weight of gas 2
M1 = molecular weight of gas 1
Accuracy vs. Precision in science
A measurement system can be accurate but not precise, precise but not accurate, neither, or both.
For example, if an experiment contains a systematic error, then increasing the sample size generally increases precision but does not improve accuracy. The result would be a consistent yet inaccurate string of results from the flawed experiment. Eliminating the systematic error improves accuracy but does not change precision.
producers > primary consumers > secondary consumers > decomposers (tertiary consumers)
Which ion would you expect to dominate in water solutions of bases?
As a general rule of thumb, for acid solutions [H+] > [OH-], for basic solutions [H+] < [OH-], for the neutral solutions or for pure water [H+] = [OH-]
Why doesn't a raindrop accelerate as it approaches the ground?
A) Gravity pulls it down at a constant rate.
B) Air resistance balances the gravitational force.
C) It's mass decreases, decreasing its speed.
D) Objects in motion decelerate over distance.
B) Air resistance balances the gravitational force.
Gravity in fact causes acceleration, making choice A incorrect--unless air resistance counteracts that acceleration, which it may easily do for an object as small and lightweight as a raindrop. Raindrops may lose mass (choice C)_, that that would not decrease their acceleration. Choice D violates Newton's first law of motion.
Formula for constant of variation
k= m(slope) or the constant of variation
used in figuring out slopes/variations in graphs
The dorsal body cavity is ______ to the ventral body cavity.
The dorsal body cavity contains the spinal column, making it posterior or toward the back of the body, compared to the ventral body cavity, which contains the structures of the chest and abdomen.
Which is a major difference between eukaryotic and prokaryotic cells?
A) Eukaryotes have DNA, and prokaryotes have RNA.
B) Eukaryotes are animal cells, and prokaryotes are plant cells.
C) Eukaryotes have nuclei, and prokaryotes have no nuclei.
D) Eukaryotes house ribosomes, and prokaryotes have no ribosomes.
C) Eukaryotes have nuclei, and prokaryotes have no nuclei.