Biology Exam Study Guide

Nonpolar molecules

A molecule that has an equal distribution of electrical charge across all its constituent atoms.

Biosphere

All parts of the planet with living things

Ribosome

An organelle that functions in the synthesis of proteins

Differences between plant and animal cells

Animal cells do not have rigid cell walls, plant cells have chloroplasts and contain chlorophyl, and plant cells have a larger central vacuole

Radioactive Isotopes

Atoms that are unstable, meaning they decay, or break down, to form stable atoms of a different element

Cell

Basic unit of life

Aerobic

Chemical reactions that require the presence of oxygen. More ATP

Levels of Structural Organization

Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species

Mitochondria

Powerhouse of the cell, organelle that is the site of ATP (energy) production

Phases of Mitosis

Prophase, prometaphase, metaphase, anaphase, telophase

Sister Chromatids

Replicated forms of a chromosome joined together by the centromere and eventually separated during mitosis or meiosis II.

Conclusion

Restates hypothesis, says if it was correct, why/why not, and what you would have done differently

Path of a Protein

Rough E.R. - Vesicle - Golgi - Vesicle - Plasmic membrane

Amino Acids

Simple forms of protein normally used to build tissues or, under some conditions, burned for energy

Rough Endoplasmic Reticulum

System of internal membranes within the cytoplasm. Membranes are rough due to the presence of ribosomes. functions in transport of substances such as proteins within the cytoplasm

Passive Transport

The movement of materials through a cell membrane without using energy

Cell Theory

The theory that cells form the fundamental structural and functional units of all living organisms

Dominant Traits

Traits that always show in a person even if only one gene of the pair is inherited for the trait

Punnett Square

a chart that shows all the possible combinations of alleles that can result from a genetic cross

Solvent

a liquid substance capable of dissolving other substances

Probability

a measure of how likely it is that some event will occur

Glycolysis

a metabolic process that breaks down carbohydrates and sugars through a series of reactions to either pyruvic acid or lactic acid and release energy for the body in the form of ATP

Cytoskeleton

a microscopic network of actin filaments and microtubules in the cytoplasm of many living cells that gives the cell shape and coherence

Solution

a mixture in which one substance is dissolved in another

Nucleus

a part of the cell containing DNA and RNA and responsible for growth and reproduction

Fermentation

a process in which an agent causes an organic substance to break down into simpler substances. Releasing ATP

Isotonic solution

a solution in which the concentration of solutes is essentially equal to that of the cell which resides in the solution

Centromere

a specialized condensed region of each chromosome that appears during mitosis where the chromatids are held together to form an X shape

Equilibrium

a state of balance

Cell Wall

a thin membrane around the cytoplasm of a cell

ATP

adenosine triphosphate, an organic molecule that acts as the main energy source for cell processes; composed of a nitrogenous base, a sugar, and three phosphate groups

Controlled Experiments

an experiment in which only one variable is manipulated at a time.

Haploid

an organism or cell having only one complete set of chromosomes

Diploid

an organism or cell having two sets of chromosomes or twice the haploid number

Consumers

an organism that obtains energy and nutrients by feeding on other organisms or their remains.

Cancer

any malignant growth or tumor caused by abnormal and uncontrolled cell division

Chlorophyll

any of a group of green pigments found in photosynthetic organisms

Isotopes

atoms of the same element that have different numbers of neutrons

Chemical Reactions

breaking of old and formation of new chemical bonds that result in new substances

Mitosis

cell division in which the nucleus divides into nuclei containing the same number of chromosomes

Meiosis

cell division that produces reproductive cells in sexually reproducing organisms

Compounds

combination of 2 or more elements

Polygenic Inheritance

combined effect of two or more genes on a single character

Heterotrophs

consumers, they rely on other organisms for their energy and food supply

Osmosis

diffusion of molecules through a semipermeable membrane from a place of higher concentration to a place of lower concentration until the concentration on both sides is equal

Ions

electrically charged atoms that have gained or lost electrons.

Themes of Biology

energy/ system and interactions/structure and function / unity with diversity/ evalution/ homeostasis/ cooperation

Variables

factors that can change in an experiment

Species

group of similar organisms that can breed and produce fertile offspring

Populations

groups of individuals that belong to the same species and live in the same area

Heterozygous

having dissimilar alleles at corresponding chromosomal loci

Homozygous

having identical alleles at corresponding chromosomal loci

Monohybrid cross

hybridization using a single trait with two alleles (as in Mendel's experiments with garden peas)

Dihybrid Cross

hybridization using two traits with two alleles each

Types of Chemical Bonds

hydrogen, covalent, ionic

Hypotonic solution

in cells, solution in which the concentration of dissolved substances is lower in the solution outside the cell than the concentration inside the cell; causes a cell to swell and possibly burst as water enters the cell

Hypertonic solution

in cells, solution in which the concentration of dissolved substances outside the cell is higher than the concentration inside the cell; causes a cell to shrink as water leaves the cell

Data

information gathered from observations

Inference

logical conclusion

Carbohydrates

main source of energy for the body

pH

measure of how acidic or basic a solution is

Lysosome

membrane-bound sac containing digestive enzymes that can break down proteins, nucleic acids, and polysaccharides

Polar molecules

molecules in which the charges are unevenly distributed; they can attract each other

Organic Molecules

molecules that contain carbon

Smooth Endoplasmic Reticulum

no ribosomes are found on surface; contains collection of enzymes that perform special tasks that include the synthesis of membrane lipids and detoxification; the liver contains a lot of smooth er

Inorganic Molecules

non-carbon based molecules

Lipids

nonpolar molecules that are not soluble or mostly insoluble in water

Proteins

nutrients that help build and maintain body cells and tissues

Cytokinesis

organic process consisting of the division of the cytoplasm of a cell following karyokinesis bringing about the separation into two daughter cells

Eukaryotes

organisms made up of one or more cells that have a nucleus and membrane-bound organelles

Producers

organisms that make their own food

Autotrophs

organisms that use energy from sunlight or from chemical bonds in inorganic substances to make organic compounds

Chloroplast

plastid containing chlorophyll and other pigments

Hypothesis

possible explanation for a set of observations or a suggested answer to a scientific question

Plasma membrane characteristics

primarily phospholipid bilayer, hydrophilic with a polar head consisting of a phosphate group and glycerol, hydrophobic with a non polar tail consisting of fatty acids, not very rigid (eukaryotic plasma membranes contain sterols and are more rigid with the exception of mycoplasm) protein molecules throught the membrane.

Diffusion

process by which molecules tend to move from an area where they are more concentrated to an area where they are less concentrated

Photosynthesis

process by which plants and some other organisms use light energy to convert water and carbon dioxide into oxygen and high-energy carbohydrates such as sugars and starches

Anaerobic

process that does not require oxygen. Makes less ATP

Subatomic particles and their characteristics

proton (+), neutron (o), electron (-)

Calvin Cycle

reactions of photosynthesis in which energy from ATP and NADPH is used to build high-energy compounds such as sugars

Krebs Cycle

second stage of cellular respiration, in which pyruvic acid is broken down into carbon dioxide in a series of energy-extracting reactions

Cell Cycle

series of events that cells go through as they grow and divide

Prokaryotes

single-celled organisms that do not have a membrane-bound nucleus

Codominance

situation in which both alleles of a gene contribute to the phenotype of the organism

Enzyme

specialized proteins that speed up chemical reactions

Golgi Apparatus

stack of membranes in the cell that modifies, sorts, and packages proteins from the endoplasmic reticulum

Catalyst

substance that speeds up the rate of a chemical reaction

Solute

the dissolved substance in a solution

Products

the elements or compounds produced by a chemical reaction

Reactants

the elements or compounds that enter into a chemical reaction

Crossing Over

the interchange of sections between pairing homologous chromosomes during the prophase of meiosis

homeostasis

the maintenance of stable internal conditions

Cellular Respiration

the metabolic processes whereby certain organisms obtain energy from organic molecules

Active Transport

the movement of materials through a cell membrane using energy

Atomic Number

the number of protons in the nucleus of an atom

Cell Specialization

the process in which cells develop in different ways to perform different tasks

Independent assortment

the random distribution of the pairs of genes on different chromosomes to the gametes

Chromosomes

threadlike structures made of DNA molecules that contain the genes.

Atomic Mass

total mass of the protons and neutrons in an atom, measured in atomic mass units

Recessive Traits

traits that typically do not show in a person unless both genes for the trait are inherited

Nucleic Acids

very long organic compounds made up of carbon, hydrogen, nitrogen, and phosphorous, contain instructions that cells need to carry out all the functions of life

Theory

well-tested explanation that unifies a broad range of observations