EOCT ReviewBiology EOCT: May 14th, 2013

Cell Structure

What is the difference between a prokaryote and eukaryote?

• Prokaryote: NO nucleus, only cytoplasm, cell membrane, ribosomes and DNA◦Small, unicellular

• Eukaryote: Nucleus, as well as cytoplasm, cell membrane, ribosomes and other organelles◦Larger, multicellular

What are the main differences between plant and animal cells?

• Plant: cell wall, chloroplast, large central vacuole; autotrophic

• Animal: lysosomes, centrioles; heterotrophic

Tell the function of the following organelles:

◦ Nucleus: contains instructions for building proteins (DNA)

◦ Ribosome: synthesizes (makes) proteins

◦ Mitochondria: performs cell respiration; provides energy

◦ Chloroplast: performs photosynthesis; provides energy

◦ Golgi apparatus/body: processes and packages proteins

◦ Cell membrane: regulates what enters and leaves the cell

◦ Cell wall: provides extra protection

◦ Vacuole: stores food, water and other essential nutrients

The cell membrane is said to have selective permeability. What does that mean?

• Only certain things can enter and leave; it “selects” what goes in and out

Cell Transport

What is the difference in passive and active transport?

• Passive Transport: moves molecules down the concentration gradient from an area of high concentration to an area of low concentration; no energy required

• Active Transport: moves molecules up the concentration gradient from an area of low concentration to an area of high concentration; energy required

What is the difference in diffusion, facilitated diffusion and osmosis? What are specific molecules that use these processes?• Diffusion: moves small molecules directly through the cell

membrane; carbon dioxide and oxygen

• Facilitated Diffusion: moves large molecules through the cell membrane using protein channels; glucose

• Osmosis: moves water molecule directly through the cell membrane

• All are types of passive transport

Explain the difference in a hypotonic, isotonic and hypertonic solution.

• Hypotonic: a solution with more water than particles; water rushes into the cell

• Isotonic: a solution with equal parts water and particles; water moves equally in and out of the cell

• Hypertonic: a solution with more particles than water; water rushes out of the cell

What is the difference in endocytosis and exocytosis?

• Endocytosis: movement of large amounts of particles into the cell; cell “engulfs”

• Exocytosis: movement of large amounts of particles out of the cell; “exit”

• Both are types of active transport

Energy- Macromolecules

and Enzymes

List and describe the function of the four macromolecules.

• Carbohydrates: provide immediate energy (sugars)

• Lipids: provide stored energy (fats)

• Proteins: build muscle and bone, fight disease, transport materials through cell membrane

• Nucleic Acid: contain instructions for building proteins (DNA and RNA)

What are the building blocks of proteins?

• Amino acids

What is an enzyme (how do they act as catalyst)? What macromolecule are they? What three letters do they usually end in?

• A protein that catalyzes (speeds up) a chemical reaction

• Protein

• -ase

What is the amount of energy needed to start a chemical reaction?

• Activation energy

What is a substrate?

• What the enzyme is doing work on

• Example: lactose is the substrate of lactase

Why is the “lock and key” analogy a good analogy to explain enzymes?

• Because just like a lock and key are specific for each other so are enzymes and substrates

Energy- Photosynthesis and

Cell Respiration

Explain what photosynthesis is and why it is so important.

• The process of using light energy (sunlight) to convert water and carbon dioxide into glucose and oxygen.

• How plants (and all autotrophs) obtain energy (make food).

Write the equation in word and formula form for photosynthesis.

Word: water + carbon dioxide glucose + oxygen

Formula: 6H2O + 6CO2 C6H12O6 + 6O2

What molecule absorbs light in the process of the photosynthesis?

• Cholorphyll

What organelle does photosynthesis take place in?

• chloroplast

What is the purpose of cell respiration?

• To break down glucose in order to make ATP

What is the energy molecule used by the cell (36 get made during cell respiration)?

• ATP

Write the equation for cell respiration in words and formula form.

• Words: oxygen + glucose carbon dioxide + water

• Formula: 6O2 + C6H12O6 6CO2 + 6H2O

What is the purpose of glycolysis (remember, all organisms use this) and how many ATP get made here? What are the other two steps of cell respiration (the two where most of the ATP gets made and only happen in eukaryotes)?

• Glycolysis: breaks down glucose into two molecules of pyruvic acid

• 2 ATP made

• Krebs Cycle and Electron Transport Chain (ETC)

What organelle does cell respiration take place in?

• Glycolysis: cytoplasm

• Krebs and ETC: mitochondria

How are photosynthesis and cell respiration related to each other?

• The products of one are the reactants of the other.

Protein Synthesis and Cell

Reproduction

What are the base pairs of DNA? Of RNA? Which ones pair together?

• DNA:◦ Adenine (A) and Thymine (T) ◦Cytosine (C) and Guanine (G)

• RNA: ◦Adenine (A)◦Uracil (U)◦Cytosine (C)◦Guanine (G)

What is DNA replication? Why is it important?

• Duplication of a DNA molecule (copying)

• So that when cells divide, the new cell made has an identical copy of DNA to the original

What is transcription?

• The transcribing of the information in a DNA molecule to an mRNA molecule.

• DNA giving its information to mRNA

What is translation?

• Using the information of mRNA to make a protein.

There are three types of RNA: mRNA, tRNA and rRNA. Explain the role of each one.• mRNA: messenger RNA; takes DNAs message to the rest of the cell

• tRNA: transfer RNA; takes amino acids to the ribosome

• rRNA: ribosomal RNA; makes up structure of ribosomes

Explain the processes of mitosis and cytokinesis.

• Mitosis: division of the nucleus; has four phases: prophase, metaphase, anaphase and telophase (PMAT)

• Cytokinesis: division of the cytoplasm

Briefly describe the four phases of mitosis.

• Prophase: nuclear membrane disappears, chromosomes appear

• Metaphase: chromosomes line up along equator of cell

• Anaphase: chromosomes separate at centromere and move to opposite poles

• Telophase: nuclear membrane forms around each group of chromosomes

What is the difference in a haploid and diploid cell?

• Haploid: has half the number of chromosomes (humans have 23); gametes (sperm and egg)

• Diploid: have a full set of chromosomes (humans have 46); body cells

How many cells do you end up with at the end of meiosis? What type of cells are they?

• Four

• Haploid; Gametes

Distinguish between the following mutations: insertion, deletion, substitution

• Insertion: an extra nucleotide is inserted into a DNA strand

• Deletion: a nucleotide is deleted from a DNA strand

• Substitution: one nucleotide is substituted for another

What are the advantages and disadvantages of sexual and asexual reproduction?• Sexual:◦Advantage: genetic diversity◦Disadvantage: slow

• Asexual:◦Advantage: fast◦Disadvantage: no genetic diversity

Genetics

Explain what the following terms mean:

◦ Dominant: allele that shows when more than one is present (AA or Aa)

◦ Recessive: allele that shows only when two copies are present (aa)

◦ Gene: piece of DNA that codes for a specific trait

◦ Allele: different forms of a trait (blue eyes, brown eyes)

◦ Genotype: the genetic material of an organsims

◦ Phenotype: the physical characteristics of an organism

◦ Homozygous: two of the same allele (AA or aa)

◦ Heterozygous: two different alleles (Aa)

◦ Monohybrid: punnett square that looks at one trait (4 squares)

◦ Dihybrid: punnett square that looks at two traits (16 squares)

 Explain Mendel's three laws:

• Law of Dominance: some alleles are dominant and some are recessive

• Law of Segregation: alleles segregate (separate) independently of each other; one copy goes to each gamete

• Law of Independent Assortment: genes for different traits can segregate independently during the formation of gametes (meaning that just because an organism is dominant for one trait doesn’t mean they will be dominant for all)

What is the main source of genetic variation?

• mutations

Ecology

List the levels of organization and give a brief description of each.

• Organism: one single individual (lion)

• Population: a group of the same organisms (lions)

• Community: different populations that live in the same area (lions, giraffes, elephants)

• Ecosystem: all the organisms in one area along with the non-living factors (lions, giraffes, elephants, waterhole, frequent fires, dry soil)

• Biome: group of ecosystems that have same climate (savanna, tundra, rainforest)

What is a series of steps that shows how energy flows through an ecosystem?

• Food chain

What amount of energy is transferred from one trophic level to the next? In an ecosystem, if the producer has 6000 kcal of energy, how much energy would the quaternary consumer have?

• 10 % of energy is transferred

Producer: 6000 Primary Consumer: 600

Secondary Consumer: 60 Tertiary Consumer: 6

Quaternary Consumer: 0.6

Distinguish between the following: producer/autotroph and consumer/heterotroph. Give an example of each.

• Producer/autotroph: makes own food via photosynthesis or chemosynthesis◦Plants, algae

• Consumer/heterotroph: must consume food◦Animals, fungi

Distinguish between abiotic and biotic. Give examples of each.

• Abiotic: nonliving factors that affect an ecosystem (rocks, soil, temperature)

• Biotic: living factors that affect an ecosystem (plants, animals, fungi, bacteria)

Explain how the following cycle through the environment (how they get to earth from the atmosphere and then back to the atmosphere) • Carbon cycle: carbon dioxide enters from atmosphere, taken in by

plants. Released by respiration from animals, decomposition, burning of fossil fuels, emissions

• b. Nitrogen cycle: nitrogen comes from atmosphere to soil, bacteria convert to useable form (nitrogen fixation), taken up by plants, eaten by animals, back to ground from death and decomposition

• c. Phosphorous cycle: rocks erode, goes into soil, plant takes it up, animals eat, returns to soil by excretion of waste or death and decomposition

Explain biomagnification. Why are pesticides greater in organisms higher on the food chain?

• Increasing concentration of a harmful substance in organisms at higher trophic levels in a food chain

• Because they eat everything below them that has the pesticides in it

Describe the difference in primary and secondary succession.

• Primary succession: regrowth of an area that has no soil, only rock (after a volcanic eruption)

• Secondary succession: regrowth of an area that still has soil (after land has been cleared)

• The first organism to appear in both areas is lichens

Put these organisms in the order they would appear during succession: trees, shrubs, lichens and moss, grass.

• Lichens, moss, grass, shrubs, trees

Describe these relationships: commensalism, mutualism, parasitism 

• Commensalism: one organism is helped and the other is neither helped or hurt (barnacles on a whale)

• Mutualism: both organisms benefit (flowers and insects)

• Parasitism: one organisms benefits and the other is hurt (tick on a dog)

Explain the difference in exponential and logistic growth. Draw a basic graph for each.

• Exponential: individuals in a population reproduce in a constant rate

• Logistic: when a population’s growth slows or stops following a period of exponential growth

What is carrying capacity?

• The maximum number of organisms a given environment can support

What is the difference between density-dependent and density-independent limiting factors? Give examples of each.• Density-dependent limiting factors: a limiting factor that

depends on population size; become limiting only when a population becomes a certain size◦Competition, predation, parasitism and disease

• Density-independent limiting factors: limiting factors that affect all populations in similar ways regardless of size◦Unusual weather, natural disasters, human activities

Organisms

Giant pandas are scientifically named Ailuropoda melanoleuca. Which part of the name represents the genus and which part represents the species?

• Ailuropoda = Genus

• Melanoleuca = species

What are the seven taxonomic categories in Linnaeus’s system of classification?

• Kingdom

• Phylum

• Class

• Order

• Family

• Genus

• Species

Why are viruses not considered to be living organisms?

• They must be in a host cell in order to survive and reproduce

What are the six kingdoms? Which are prokaryote and which are eukaryote?

• Bacteria: prokaryote

• Archaea: prokaryote

• Protista: eukaryote

• Fungi: eukaryote

• Plantae: eukaryote

• Animalia: eukaryote

What is homeostasis and why is it important for organisms to maintain it?

• Maintaining a constant/stable internal environment

• To prevent death

List the characteristics all living things share.

• Have cells

• Reproduce

• Have DNA

• Grow and develop

• Need energy

• Respond to the environment

• Evolve

• Maintain homeostasis

Bacteria and archaea reproduce asexually by binary fission. What is binary fission?

• When unicellular organisms make a copy of their DNA once they have doubled in size and then split in half.

What components make up a virus?

• Nucleic Acid (DNA or RNA) and a protein coat (the capsid)

Organisms- Plant and Animal Behavior

What is a tropism?

• A plants response to its environment

Explain the difference between the following tropisms:

◦Geo/Gravitropism: a plants response to gravity◦Phototropism: a plants response to light◦Thigmotropism: a plants response to touch

Hormones are important for plants. What do auxins and gibberellins do for plants?

• Auxins: stimulate cell growth in height

• Gibberellins: stimulate cell growth in size (girth, width)

What is the difference in an innate and learned behavior?

• Innate: instinct, a behavior that is not taught

• Learned: a behavior that is taught and grasped through experience

What is the difference in hibernation and migration?

• Hibernation: act of an organism entering a state of dormancy for a season; the organism stays in one area

• Migration: the act of relocating to another area for a season

Evolution

Which scientist said that organisms acquired traits during their lifetime by use and disuse and could then pass these traits to their offspring.

• Lamarck

What is Charles Darwin’s theory of evolution called?

• Natural Selection

Explain what natural selection is.

• When nature “selects” the adaptations that will allow an organism to best survive and reproduce in its environment.

What is an adaptation?

• A feature an organism has that allows it to survive and reproduce successfully in its environment.

What is genetic variation and what does it have to do with natural selection?

• Variation- differences among species

• Without variation, there would be no natural selection

Where does genetic variation within organisms come from?

• Variation can come from ◦Mutations◦Recombination (crossing-over)◦Environmental conditions

Describe a vestigial structure, homologous structure and analogous structure.  • Vestigial Structure: something that is present

but not needed in order for the organism to survive and reproduce

• Homologous Structure: structures that have a similar structural makeup but different functions

• Analogous Structure: structures that have different structural makeup's but the same function

How do fossils help back up Darwin’s evolutionary theory?

• Showed that species had changed over time and that species that were once living were not living today.

How can pesticides and antibiotics be used to show how evolution works?

• Resistance can occur which shows that organisms have the ability to adapt and change as their environment does.

1. Unlike prokaryotic cells, eukaryotic cells have the capacity to

A. assemble into multi-cellular organisms

B. establish symbiotic relationships with other organisms

C. obtain energy from the Sun

D. store genetic information in the form of DNA

2. Inside eukaryotic cells are membrane -bound structures called

A. cell walls

B. cilia

C. organelles

D. cytoplasm

3. The function of this cell organelle is to produce energy. What is the name of this organelle?

A. Golgi apparatus

B. mitochondrion

C. nucleus

D. ribosome

4. Which of the following examples illustrates osmosis?

A. Water leaves the tubules of the kidney in response to the hypertonic fluid surrounding the tubules.

B. Digestive enzymes are excreted into the small intestine.

C. White blood cells consume pathogens and cell debris at the site of an infection.

D. Calcium is pumped inside a muscle cell after the muscle completes its contraction.

5. Enzymes are proteins that speed up a chemical reaction. They do so by

A. Weakening activation energy.

B. Raising the bond strength and activation energy of the substrate molecules.

C. The enzymes are able to lower the activation energy that is needed for the reaction to occur.

D. The enzymes are able to raise the activation energy that is needed for the reaction to occur.

 

6. In glycolysis, the first stage of cellular respiration, ATP molecules are produced. What is the net gain of ATP molecules (per molecule of glucose) from glycolysis?

A. 1

B. 2

C. 4

D. 36

7. One main difference between members of the Kingdoms Plantae and Animalia is the ability to

A. obtain energy

B. reproduce

C. move

D. exchange gases

8. Information on mRNA is used to make a sequence of amino acids into a protein by which of the following processes?

A .replication

B. translation

C. transcription

D. transference

9. In rabbits, black fur (B) is dominant over brown fur (b). If one parent rabbit is heterozygous (Bb) and the other parent rabbit is homozygous brown (bb), what is the probability of producing an offspring with brown fur? Use the Punnett square to determine your answer.

A. 25%

B. 50%

C. 75%

D. 100%

10. When an organism has two different alleles for a trait, it is said to be

A. recessive

B. dominant

C. homozygous

D. heterozygous

11. What is a source of genetic variation?

A. adaptation

B. mutation

C. respiration

D. transpiration

12. Why is it important for the cells of multi-cellular organisms to undergo mitosis?

A. Mitosis allows for reproduction with male and female gametes.

B. Mitosis increases variation within an organism.

C. Mitosis produces cells that are different from the original dividing cell.

D. Mitosis produces identical cells to the original dividing cell

13. In the food chain below, which population will most likely decrease if snakes are removed from the food chain?

grass grasshopper frog snake hawk

A. grass

B. grasshopper

C. frog

D. hawk

14. Which element’s cycle depends on certain kinds of bacteria to keep the element available to other organisms?

A. carbon

B. hydrogen

C. nitrogen

D. phosphorus

15. The theory of global warming suggests that a trend toward warmer temperatures on Earth will cause glaciers to lose mass. Which result is a major consequence of glacial melting?

A. flooding coastal regions

B. destruction of fossil records

C. increased saltiness of the oceans

D. an increase in atmospheric carbon dioxide

16. Ancestors of the koala lived on the ground, but modern koalas live in trees and eat eucalyptus leaves, which are poisonous to most other animals. The difference between the ancestor and modern koalas was caused by

A. the presence of homologous structures

B. the presence of vestigial organs

C. selective breeding

D. natural selection

 

17. Horses and tapirs have a common ancestor, but they now look very different from one another. Horses are now grassland animals adapted for grazing on grass and shrubs. Tapirs are jungle animals that live in dense forests and eat fruit, leaves, and aquatic vegetation. Which of the following led to the development of such differences in the two species?

A. selective breeding

B. convergent evolution

C. DNA hybridization

D. natural selection

18. Fossils of Archaeopteryx show that this animal had feathers, like a bird. It also had a bony tail, teeth, and claws on its wings, like a reptile. These fossils are evidence that support the idea that

A. birds and reptiles have a common ancestor

B. birds have changed very little over millions of years

C. reptile species are more advanced than bird species

D. reptiles are warm-blooded like birds

19. Although the arctic fox and the kit fox are closely related, they look very different because the individuals

A. acquired traits during their lifetimes that contributed to survival

B. with traits most suited to their environment reproduced most successfully

C. migrated long distances to environments that most suited their traits

D. passed on to their offspring acquired behaviors that were helpful

20. Some viral diseases require only one vaccination, which lasts for years. For other diseases such as the flu, vaccinations last only one season. The flu vaccine lasts such a short time because the flu virus

A. is more easily transmitted than other viruses

B. mutates much more rapidly than other viruses

C. is less dangerous than other viruses

D. is much smaller than other viruses