Biol 101 Hoefnagels Concepts & Investigations Final Exam

What is science?

an objective, logical, and repeatable attempt to understand the principles and forces operating in the natural universe

What is biology?

the scientific study of life

What is chemistry?

the science of matter, which deals with the composition of substrates and their properties and reactions

What are the characteristics of life?

-Composed of one or more cells

-Require ongoing inputs of energy and raw materials

-Sense and respond to change

-Grow, develop, and reproduce

-Pass DNA to offspring

What is a cell?

the smallest unit of life

What is a cell composed of?

All cells have a plasma membrane and cytoplasm, and they all start out life with DNA

What are the two basic types of cells?

-Eukaryotic Cell- includes a nucleus

-Prokaryotic cell- without a nucleus

Who is the father of taxonomy?

Carolus Linnaeus

What are the levels of hierarchy of taxonomy?

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

List the three domains and the kingdoms of each domain

1. Bacteria - Eubacteria

2. Archaea -Archaebacteria

3. Eukarya (Eukaryotes) - Fungi, Protists, Plants, Animals

What is energy?

Ability to do work

What are the two forms of energy?

-Potential Energy: Stored Energy available to do work

-Kinetic Energy: Energy in motion

What is an atom?

the building blocks of all substances, which are made up of electrons, protons, and neutrons

How do you determine the atom's atomic number?

number of protons

How do you determine the atom's mass number?

Total protons and neutrons in a nucleus

What is an orbital?

Electrons move around nuclei in orbitals

How many electrons can an orbital hold?

Two electrons

What is a valence shell?

Outermost occupied energy shell

What is an ion?

An atom with a positive or negative charge due to loss or gain of electrons in its outer shell

What is an isotope?

Different forms of the same element, with different numbers of neutrons

What is a chemical bond?

An attractive force existing between two atoms when their electrons interact

What is a covalent bond?

Occur when electrons from different atoms share a space in a shell (can be stronger than ionic bonds)

What is an ionic bond?

A strong mutual attraction between two oppositely charged ions

What is a hydrogen bond?

A weak attraction between a highly electronegative atom and a hydrogen atom taking part in a separate polar covalent bond

What are the properties of water?

Solvent, Has cohesion, Stabilizes temperature

What is cohesion?

Water molecules from hydrogen bonds with other water molecules

What is adhesion?

Tendency to form hydrogen bonds with other substances

What is the difference between a hydrophobic and hydrophilic solution?

-Hydrophobic molecules are not dissolved by water.

-Hydrophilic molecules are polar molecules that are dissolved by water.

List the macromolecules and their monomers.

- Proteins: Amino Acids

- Nucleic Acids: Nucleotides

-Lipids: Glycerol and Fatty Acids

- Carbohydrates: Monosaccharides (sugars)

List the tenets of the cell theory.

-All organisms consist of one or more cells

-A cell is the smallest unit with the properties of life

-Each new cell arises from division of a preexisting cell

-Each cell passes its hereditary material to its offspring

What is a microscope?

an instrument that magnifies an image

What is a light microscope?

Visible light illuminates a sample

What is the advantage of a light microscope?

light beam does not kill the cells; less expensive

What is the disadvantage of a light microscope?

Limitation in the amount of detail that can be revealed due to lower resolution and magnification

What is an electron microscope?

Use magnetic fields as lenses to focus a beam of electrons onto a sample

What is the advantage of an electron microscope?

Greater magnification and High resolution

What is the disadvantage of an electron microscope?

More expensive; Sample preparation is often more elaborate

Who is Antonie van Leeuwenhoek?

The first to describe small organisms seen through a microscope, which he called animalcules and beasties

List the organelles and their functions?

-Nucleus- Protecting, controlling access to DNA

-Endoplasmic Reticulum- Routing, modifying new polypeptide chains; synthesizing lipids

-Golgi Body- Modifying new polypeptide chains; sorting, shipping proteins and lipids

-Vesicles- Transporting, storing, or digesting substances in a cell

-Mitochondrion- Making ATP by glucose breakdown

-Chloroplast- Photosynthesis in plants

-Lysosomes- Intracellular digestion

-Peroxisome- Inactivating toxins

-Vacuole- Storage

-Ribosomes- Assembling polypeptide chains

-Centriole- Anchor for cytoskeleton

-Cytoskeleton- contributes to cell shape, internal organization, movement

-Rough ER- Modifies proteins made by ribosomes attached to it

-Smooth ER- Makes lipids, breaks down carbohydrates and fats, and inactivating toxins

What is energy?

the ability to do work

What are the two forms of energy?

-Potential Energy: Stored energy

-Kinetic Energy: Energy in motion

What are the two laws of thermodynamics?

-1st Law: Energy is neither created nor destroyed, but can be transferred from one form to another

-2nd Law: Every energy transfer some portion of the available energy is degraded to heat which moves to cooler objects

What is ATP?

A nucleotide with ribose and with three phosphate groups; transfers a phosphate group and energy to other molecules

What is an enzyme?

Makes a specific reaction occur much faster than it would on its own during catalysis

What is the difference between passive and active transport?

-Passive Transport: Requires no energy input

-Active Transport: Requires energy input (Usually ATP)

What are some examples of passive transport?

Diffusion, Osmosis, Facilitated Diffusion

What is osmosis?

The movement of water down its concentration gradient, through a selectively permeable membrane from a region of lower solute concentration to a region of higher solute concentration

What is endocytosis?

The formation of a vesicle from cell membrane, enclosing materials near the cell surface and bringing them into the cell

What is exocytosis?

The fusion of a vesicle with the cell membrane, releasing its contents to the surroundings

What is photosynthesis?

A process which uses the energy of sunlight to assemble carbohydrates from carbon dioxide and water

What is a chloroplast?

An organelle that specializes in photosynthesis in plants and many protists

Describe the structure of the chloroplast.

A double membrane surrounding a dense fluid called the stroma and elaborate membrane system called thylakoids, enclosing the thylakoids space. Thylakoid sacs may be stacked to form grana. Chlorophyll is embedded in the thylakoid membrane.

What are the two stages of photosynthesis and what occurs in each stage?

Light reactions uses solar energy to make ATP and NADPH, which supply chemical energy and reducing power, respectively, to the Calvin cycle. The Calvin cycle incorporates CO2 into organic molecules, which are converted to sugar.

What is the reactants of photosynthesis?

6 CO2 + 6 H2O + Light

What is the product of photosynthesis? C6H12O6 + 6O2

C6H12O6 + 6O2

What is the byproduct of photosynthesis?

Oxygen

What is the primary pigment needed for photosynthesis?

Chlorophyll a

What are accessory pigments?

Chlorophyll & Carotenoids

What are the three main processes of aerobic respiration?

Glycolysis, Krebs Cycle, and Electron Transport System

In eukaryotes, for each processes of aerobic respiration where does it occur?

Mitochondria

What are the reactants for aerobic respiration?

glucose & oxygen

What are the products of aerobic respiration?

carbon dioxide & water

What is DNA replication?

The process of making 2 identical daughter strands from a parental strand of DNA

Describe the DNA replication process.

-DNA uncoils/unwinds

-DNA helicase breaks the hydrogen bonds and "unzips" the DNA

-DNA polymerase moves along the DNA strands attaching free floating nucleotides to the open strands

-DNA "rezips" and "recoils"

What is mitosis?

A nuclear division mechanism that maintains the chromosome number

What is cytokinesis?

The process of cytoplasmic division

Descibe interphase.

Consists of three stages, during which a cell increases in size, doubles the number of cytoplasmic components, and replicates its DNA

Describe prophase.

Chromosomes condense, microtubules form a bipolar spindle, nuclear envelope breaks up

Describe metaphase.

All duplicated chromosomes line up midway between the spindle pores

Describe anaphase.

Microtubules separate the sister chromatids of each chromosome and pull them to opposite spindle poles

Describe telaphase.

Two clusters of chromosomes reach the spindle poles; a new nuclear envelope forms around each cluster

Describe how cytokinesis occurs in animals.

A cleavage furrow partitions the cytoplasm

Describe how cytokinesis occurs in plants.

A cell plate forms midway between the spindle poles; it partitions the cytoplasm when it reaches and connects to the parent cell wall

What does it mean that a cell is diploid?

Having two of the basic sets of chromosomes in the nucleus (2n)

What does it mean that a cell is haploid?

having a single set of unpaired chromosomes

Describe the structure of a chromosome.

Rod-shaped structure; made of DNA and proteins

What is meiosis?

Division of genetic material that halves the chromosome number and yields genetically variable gametes

Describe the phases of Meosis 1.

-Prophase 1 - replicated chromosomes condense, homologs pair, crossing over occurs, spindle forms

-Metaphase 1 - paired homologs line up and down the center of the cell

-Anaphase 1 - homologs split

-Telophase 1 -chromosomes reach opposite poles

-Cytokinesis

Describe the phases of Meosis 2.

-Prophase 2 - chromosomes condense again

-Metaphase 2 - chromosomes line up

-Anaphase 2 - sister chromatids split

-Telophase 2 -chromosomes reach opposite poles, nuclear envelope reforms

What are germ cells?

Immature reproductive cells

What is crossing-over?

The process by which a chromosome and its homologous partner exchange heritable information in corresponding segments

What are some errors that can occur in meiosis?

Genetic Disorders; Down Syndrome

What is fertilization?

The fusion of two haploid gametes (sperm and egg) resulting in a diploid zygote

What is a zygote?

The first cell of a new individual

What is genetics?

The study of heredity and the variation of inherited characteristics

What is a gene?

heritable units of information about traits

What is an allele?

different molecular forms of a gene

What is the difference between phenotype and genotype?

-Genotype: Particular set of alleles that an individual carries

-Phenotype: An individual's observable traits

What does homozygous mean?

An individual with two identical alleles of a gene

What does heterozygous mean?

An individual with non-identical alleles of a gene

What does it mean if an allele is dominant?

its effect masks the effect of the recessive alleles paired with it

What does it mean if an allele is recessive?

An allele that is masked when a dominant allele is present

What is a Punnett square?

A grid used to calculate the probability of genotypes and phenotypes in offspring

What is a test cross?

A method of determining if an individual is heterozygous or homozygous dominant

Describe Mendel's law.

During meiosis, members of a pair of genes on homologous chromosomes get distributed into gametes independently of other gene pairs

What is a food chain?

Description of who eats whom in one path of energy flow in an ecosystem

What is a trophic level?

Position of an organism in a food chain

What is a biome?

Group of regions that may be widely separated but share a characteristic climate and dominant vegetation

Describe the desert biome.

Biome with little rain and low humidity; plants with water-storing and water-conserving adaptations predominate

Describe the grasslands biome.

Biome in the interior of continents where grasses and non-woody plants adapted to grazing and fire predominant