Bio Final

Question 1

Review life’s organization ie from cell to organism

Answer 1

atom, molecule, cell, tissue, organ, organ system, organism, species, population, community, ecosystem, biome

Question 2

The three domains

Answer 2

Archaea, Bacteria, Eukarya

Question 3

Binomial name system

Answer 3

Domain, kingdom, phylum, class, order, family, genus, species. Binomial name is in italics and is genus and species. Genus can be abbreviated

Question 4

Scientific Process

Answer 4

Scientific method- observations, hypothesis, prediction, experiment (with control groups and single variable), conclusion.

Question 5

Review the Plasma membrane and how substances get into the cell (i.e.,
channels)

Answer 5

Acts as a boundary/gatekeeper around cell. Is made a phospholipid bilayer with numerous imbedded proteins. Also called fluid mosaic model.
Channel proteins- tunnel transport across entire membrane
Transport proteins- often combine with and help molecules and ions pass through
Receptor proteins- Allows a signal protein to bind to it. Creates cellular response
Enzymatic proteins - participate (speed up) metabolic processes
Junction proteins - assist in cell to cell adhesion and communication

Question 6

Prokaryotic vs Eukaryotic

Answer 6

Prokaryote- no membrane bound nucleus, DNA in nucleoid which is found in cytoplasm, can have a cell wall and ribosomes. Eukarotes are highly compartmentalized (organelles) and structured. They have a nucleus

Question 7

How are bacteria structured

Answer 7

They are prokaryotes. Most pocesss a cell wall and some have a capsule. cyctoplasma is surrounded by a plasma membrane. Cytoplasm has enzymes (speed up reactions). DNA is in a single coil that’s in the nucleotoid. They have RNA. Some have a flagella

Question 8

Briefly review the main organellesn(13)

Answer 8

Plasma membrane -Encloses the cytoplasm; regulates interactions with the external environment

Nucleus -Contains the genetic material (DNA); nucleolus is the site of ribosome formation

Ribosomes- Location where polypeptides and proteins are formed

Vesicles - Small sacs that move materials between organelles in the endomembrane system

Rough ER- Component of the endomembrane system that has ribosomes attached; synthesizes proteins

Smooth ER- Endomembrane system organelle where lipids and some carbohydrates are synthesized; detoxifies some chemicals

Golgi apparatus- Processing and packaging center

Lysosome- Vesicle that contains enzymes that break down incoming molecules and cellular components

Chloroplast- Site of photosynthesis and carbohydrate formation (not found in animals)

Mitochondrion- Site of cellular respiration and ATP synthesis

Cell wall- Layer of cellulose that supports cells (not found in animals)

Cytoskeleton- Internal framework of protein fibers; moves organelles and maintains cell shape

Flagella and cilia- Involved in moving the cell or moving materials along the surface of the cell

Vesicles and Vacuoles
Centrioles

Question 9

Where does photosynthesis occur

Answer 9

Photosynthesis happens in the chloroplasts. The thylakoid space contains the pigments and the stroma has the enzymes that produce the carbs.

Question 10

What is cellular respiration

Answer 10

Cellular respiration converts organic molecules into ATP adenosine triphosphate , the universal energy required by all living organisms. ATP happens in both aerobic and anaerobic environments. During cellular respiration, glucose is oxidized to CO2, which we exhale. Oxygen (O2), which we breathe in, is reduced to H2O. When glucose is oxidized, energy is released.

four phases to convert glucose into ATP.

1) Glycolysis, occurs within the cytoplasm of the cell. the breakdown of glucose to two molecules of pyruvate, is a series of enzymatic reactions. Net gain of 2 ATP

Next phases depend on if O2 is present.

Aerobic-
Remaining stages take place Inside the Mitochondria.

Phases - the preparatory (prep) reaction is so named because it prepares the outputs of glycolysis (pyruvate molecules) for use in the citric acid cycle. -Per glucose molecule, the outputs are two CO2, two NADH, and two acetyl-CoA.

The Citric Acid Cycle
Acetyl groups enter the citric acid cycle, a series of reactions occurring in the mitochondrial matrix. During one turn of the cycle, oxidation results in two CO2, three NADH, and one FADH2. One turn also produces one ATP. There are two turns of the cycle per glucose molecule.

The Electron Transport Chain
The final stage of cellular respiration involves the electron transport chain located in the cristae of the mitochondria. The chain is a series of electron carriers that accept high-energy electrons (e–) from NADH and FADH2 and pass electrons along until they are finally low-energy electrons received by oxygen, which combines with H+ to produce water.

Question 11

Difference between photosynthesis and cellular respiration

Answer 11

During photosynthesis, the chloroplasts in plants capture solar energy and use it to convert water and carbon dioxide to carbohydrates, which serve as food for themselves and for other organisms. During cellular respiration, mitochondria complete the breakdown of carbohydrates and use the released energy to build ATP molecules.

Question 12

Describe different types of bonds

Answer 12

Ionic bonding (NaCl) is when an atom gives away a bond and the other takes it. (one keeps a shell, one loses). The molecule becomes charged. (unbalanced). Covalent bonding they share an ion. Are balanced.

Question 13

Who is Gregor Mendell and what did he do with peas?

Answer 13

Gregor Mendel was an Austrian monk who, experiments in the 1860s, developed several important laws on patterns of inheritance. 7 varieties true breeding peas. did crosses, punnett square

Law of Dominance
Law of Segregation
Law of Independent Assortment

Question 14

Punnett Square

Answer 14

In a Punnett square, all possible types of sperm are lined up vertically, and all possible types of eggs are lined up horizontally, or vice versa, so that every possible combination of gametes the offspring may inherit occurs within the square.

Question 15

Dihybrid punnett square

Answer 15

• ———-AB Ab aB ab
• AB* AABB AAbB aABB aAbB
• Ab* AABb AAbb aABb aAbb
• aB* AaBB AabB aaBB aabB
• ab* AaBb Aabb aaBb aabb

The phenotype ratio predicted for dihybrid cross is 9:3:3:1. Of the sixteen possible allele combinations:
Nine combinations produce offspring with both dominant phenotypes.
Three combinations each produce offspring with one dominant and one recessive phenotype.
One combination produces a double recessive offspring.

Question 16

Genotype vs phenotype

Answer 16

The word phenotype refers to the physical appearance of the individual. An organism’s phenotype is mostly determined by its genotype. The word genotype refers to the combination of alleles in a cell or organism. Genotype may be indicated by letters or by short, descriptive phrases

Question 17

Sex Linked

Answer 17

, both males and females have 23 pairs of chromosomes; 22 pairs are called autosomes, and 1 pair is the sex chromosomes. The much shorter Y chromosome contains fewer than 200 genes, and most of these genes are concerned with sex differences between men and women. In contrast, the X chromosome is quite large and contains nearly 2,000 genes, most of which have nothing to do with the gender of the individual. By tradition, the term X-linked refers to such genes carried on the X chromosome.

Question 18

DNA Strand replication

Answer 18

During DNA replication (S phase of cell cycle), the two DNA strands, which are held together by hydrogen bonds, are separated and each old strand of the parent molecule serves as a template for a new strand in a daughter molecule (Fig. 11.6). This process is referred to as semiconservative, since one of the two old strands is conserved, or present, in each daughter molecule. the DNA double helix must separate and unwind. This is accomplished by breaking the hydrogen bonds between the nucleotides, then unwinding the helix structure using an enzyme called helicase. At this point, new nucleotides are added to the parental template strand. Nucleotides, ever present in the nucleus, will complementary base-pair onto the now single-stranded parental strand. The addition of the new strand is completed using an enzyme complex called DNA polymerase. The daughter strand is synthesized by DNA polymerase in a 5′–3′ direction, as shown in Figure 11.6. Any breaks in the sugar-phosphate backbone are sealed by the enzyme DNA ligase.synthesized by DNA polymerase in a 5′–3′ direction, as shown in Figure 11.6. Any breaks in the sugar-phosphate backbone are sealed by the enzyme DNA ligase.

Question 19

Difference DNA and RNA

Answer 19

SIMILARITIES OF DNA AND RNA
Both are nucleic acids.
Both are composed of nucleotides.
Both have a sugar-phosphate backbone.
Both have four different types of bases.

DIFFERENCES BETWEEN DNA AND RNA

DNA
Found in nucleus
Genetic material
Sugar is deoxyribose.
Bases are A, T, C, G.
Double-stranded
DNA is transcribed (to give a variety of RNA molecules).

RNA
Found in nucleus and cytoplasm
Helper to DNA
Sugar is ribose.
Bases are A, U, C, G.
Single-stranded
mRNA is translated (to make proteins).

Question 20

Types of RNA

Answer 20

The three main forms are messenger RNA (mRNA), which carries the DNA message to the ribosomes; transfer RNA (tRNA), which transfers amino acids to the ribosomes, where protein synthesis occurs; and ribosomal RNA (rRNA), which is found in the ribosomes.

Question 21

Cell Cycle

Answer 21

The cell cycle is an orderly sequence of stages that take place between the time a new cell has arisen from the division of the parent cell to the point when it has given rise to two daughter cells. It consists of interphase, the time when the cell performs its usual functions; a period of nuclear division called mitosis; and division of the cytoplasm, or cytokinesis.

Interphase- DNA replication occurs in the middle of interphase and serves as a way to divide interphase into three phases: G1, S, and G2. G1 is the phase before DNA replication, and G2 is the phase following DNA synthesis. Originally, G stood for “gap,” but now that we know how metabolically active the cell is, it is better to think of G as standing for “growth.”

M Phase= Cell division occurs during the M phase, which encompasses both division of the nucleus and division of the cytoplasm. The type of nuclear division associated with the cell cycle is called mitosis, which accounts for why this stage is called the M phase.

prophase Mitotic phase during which chromatin condenses, so that chromosomes appear. Chromosomes are scattered.

metaphase Mitotic phase during which chromosomes are aligned at the spindle equator.

anaphase Mitotic phase during which daughter chromosomes move toward the poles of the spindle.

telophase Mitotic phase during which daughter cells are located at each pole.

Question 22

Mitosis and 4 phases

Answer 22

We will describe mitosis as having four phases: prophase, metaphase, anaphase, and telophase.

prophase Mitotic phase during which chromatin condenses, so that chromosomes appear. Chromosomes are scattered.

metaphase Mitotic phase during which chromosomes are aligned at the spindle equator.

anaphase Mitotic phase during which daughter chromosomes move toward the poles of the spindle.

telophase Mitotic phase during which daughter cells are located at each pole.

Question 23

Darwin

Answer 23

Came up with theory of evolution from his trip on the Beagle where he was a naturalist. He studied the finches of the Galapogos islands. He proposed the idea of natural selection.

Question 24

Natural Selection (steps)

Answer 24

Mechanism of evolution caused by environmental selection of organisms most fit to reproduce; results in adaptation to the environment.

The members of a population have heritable
variations

The population produces more offspring than the resources of an environment can support.

The individuals that have favorable traits survive and reproduce to a greater extent than those that lack these traits.

Over time, the proportion of a favorable trait increases in the population, and the population becomes adapted to the environment.

Question 25

Types of natural selection

Answer 25

Stabilizing selection occurs when an intermediate phenotype is favored Directional selection occurs when an extreme phenotype is favored and the frequency distribution curve shifts in that direction In disruptive selection, two or more extreme phenotypes are favored over any intermediate phenotype. Therefore, disruptive selection favors polymorphism, the occurrence of different forms in a population of the same species.

Question 26

Antibiotic Resistence

Answer 26

Directional selection. Some bacteria survive. The more antibiotics used the more bacteria that are resistant to antibiotics survive (And those that aren't die). Therefor those bacteria become selected for.

Question 27

Causes of microevolution (4)

Answer 27

genetic mutation, gene flow, nonrandom mating, and genetic drift Genetic mutation - change in genes Gene flow, also called gene migration, is the movement of alleles among populations by migration of breeding individuals Nonrandom mating- Random mating occurs when individuals select mates and pair by chance, not according to their genotypes or phenotypes (includes bottleneck and founder) Genetic drift refers to changes in the allele frequencies of a gene pool due to chance. This mechanism of evolution is called genetic drift because allele frequencies “drift” over time.

Question 28

Virus

Answer 28

Viruses are obligate intracellular parasites, because they can reproduce only inside a living cell (obligate means “restricted to a specific form”). They lack the ability to acquire nutrients, or to use energy. They are incredibly small and can be produced in a labratory. has at least two parts: an outer capsid, composed of protein subunits, and an inner core containing its genetic material, which may be either DNA or RNA Viruses are specific to a particular host cell because a spike, or some portion of the capsid, adheres in a lock-and-key manner to a specific molecule (called a receptor) on the host cell’s outer surface.Once inside a host cell, the viral genome takes over the metabolic machinery of the host cell. In large measure, the virus uses this machinery, including the host’s enzymes, ribosomes, transfer RNA (tRNA), and ATP, to reproduce itself.

Question 29

Legumes and bacteria

Answer 29

Legume plants, such as soybean and peas, have roots colonized by bacteria that are able to take up atmospheric nitrogen and reduce it to a form suitable for incorporation into organic compounds (Fig. 20.17a). The bacteria live in root nodules (see Fig. 17.13), and the plant supplies the bacteria with carbohydrates, while the bacteria in turn furnish the plant with nitrogen compounds.

Question 30

Types of Archaea

Answer 30

The archaea (domain Archaea) are the second type of prokaryote. The following are some characteristics of archaea: They appear to be more closely related to the eukarya than to the bacteria. They do not have peptidoglycan in their cell walls, as do the bacteria, and they share more biochemical characteristics with the eukarya than do bacteria. Some are well known for living under harsh conditions, such as anaerobic marshes (methanogens), salty lakes (halophiles), and hot sulfur springs (thermoacidophiles).

Question 31

Five evolutionary stages of plants

Answer 31

Land plants arose from a common green algal ancestor. The evolution of land plants is marked by five significant events: (1) protection of the embryo; (bryophytes- mosses) (2) evolution of vascular tissue whihch have sylem and phloem;(lycophytes) (3) evolution of leaves (microphylls and megaphylls - ferns); (4) (gymnosperms) evolution of the seed; and (5) evolution of the flower. (angiosperms)

Question 32

Four major tissue types

Answer 32

Epithelial tissue (epithelium) covers body surfaces and lines body cavities. Connective tissue binds and supports body parts. Muscular tissue moves the body and its parts. Except for nervous tissue, each type of tissue is subdivided into even more types Nervous tissue receives stimuli and conducts nerve impulses.

Question 33

Muscle tissue

Answer 33

The three types of vertebrate muscles are skeletal, cardiac, and smooth (involuntary).

Question 34

Types of connective tissue

Answer 34

In connective tissue, cells are separated by a matrix that contains fibers (e.g., collagen fibers). The four types are Loose fibrous connective tissue, organs and including adipose tissue Dense fibrous connective tissue (tendons and ligaments) Cartilage and bone; the matrix of cartilage is more flexible than that of bone Blood; the matrix is a liquid called plasma, and the cells are red blood cells, white blood cells, and platelets (cell fragments)

Question 35

Components of neurons

Answer 35

Each neuron has dendrites (extension), a cell body (receives signal from dendrite), and an axon (axons are extensions that conduct away)

Question 36

Open and close circulatory systems

Answer 36

The circulatory system is responsible for supplying the cells of an animal with oxygen and nutrients and removing carbon dioxide and other waste materials. Some invertebrates do not have a circulatory system, because their body plan allows each cell to exchange molecules with the external environment. Other invertebrates do have a circulatory system that uses a heart to move the blood. In an open circulatory system, the fluid, called hemolymph, is not confined to the blood vessels but accumulates in cavities called sinuses, or collectively, the hemocoel. In a closed circulatory system, or cardiovascular system, the blood remains within the blood vessels.

Question 37

Cardiovascular system (compare brief)

Answer 37

The heart has a right and a left side separated by a septum. Each side has an atrium (receives blood) and a ventricle (pumps blood). Atrioventricular valves and semilunar valves keep the blood moving in the correct direction. Arteries move blood away from the heart; veins move blood toward the heart. Fishes have a one-circuit pathway of circulation because the heart, with a single atrium and ventricle, pumps blood only to the gills. The cardiovascular system of other vertebrates consists of a pulmonary circuit (moves blood to lungs) and a systemic circuit (moves blood to tissues). Amphibians have two atria but a single ventricle. Crocodilians, birds, and mammals, including humans, have a heart with two atria and two ventricles, in which O2-rich blood is kept separate from O2-poor blood.

Question 38

Respiratory System

Answer 38

To reach the lungs, air moves from the nasal cavities through the pharynx, larynx, trachea, bronchi, and bronchioles, which end in the alveoli of the lungs. Breathing: inspiration (entrance of air into the lungs) and expiration (exit of air from the lungs) External exchange of gases between the air and the blood within the lungs Internal exchange of gases between blood and interstitial fluid and the exchange of gases between the cells and interstitial fluid

Question 39

Urinary System

Answer 39

Kidneys: Produce urine Ureters: Take urine to the bladder Urinary bladder: Stores urine Urethra: Releases urine to the outsideExcretion of nitrogenous wastes, such as urea and uric acid Maintenance of the water-salt balance of the blood Maintenance of the acid-base balance of the blood

Question 40

Sympathetic vs Parasympathetic system (nerves)

Answer 40

The parasympathetic division includes a few cranial nerves (e.g., the vagus nerve) and axons that arise from the last portion of the spinal cord. The parasympathetic division, sometimes called the “housekeeper division,” promotes all the internal responses we associate with a relaxed state. Axons of the sympathetic division arise from portions of the spinal cord. The sympathetic division is especially important during emergency situations and is associated with “fight or flight.

Question 41

Plant tissue types

Answer 41

Epidermal tissue forms the outer protective covering of a plant. Ground tissue fills the interior of a plant and helps carry out the functions of a particular organ. Vascular tissue transports water and nutrients in a plant and provides support.

Question 42

Early Embryonic development

Answer 42

Fertilization Cleavage, which occurs in the uterine tube is the rapid cell division without growth. (Tightly packed cells are call a morula. Next is the formulation of the blastocyst. A fluid filled sac of cells called a blastocoel. Inner cells distinct from outer blastula. Embryo implants in the uterine lining Still part of The blastocyst implants itself in the endometrium. Gastrulation - three germ layers form: ectoderm, mesoderm, endoderm Organ formation- notochord and neuralation

Question 43

Direct (4) vs indirect values biodiversity (6)

Answer 43

The direct values of biodiversity are: Medicinal value (medicines derived from living organisms) Agricultural value (crops derived from wild plants) Biological pest controls and animal pollinators Consumptive use values (food production) Indirect Values of Biodiversity Biodiversity in ecosystems contributes to: The functioning of biogeochemical cycles (water, carbon, nitrogen, phosphorus, and others) Waste disposal (through the action of decomposers and the ability of natural communities to purify water and take up pollutants) Fresh water provision through the water biogeochemical cycle Prevention of soil erosion, which occurs naturally in intact ecosystems Climate regulation (plants take up carbon dioxide) Ecotourism (human enjoyment of a beautiful ecosystem)

Question 44

Patterns of population growth

Answer 44

The patterns of population growth are dependent on (1) the biotic potential of the species and (2) the availability of resources. The two fundamental patterns of population growth are exponential growth and logistic growth. Exponential- An exponential pattern of population growth results in a J-shaped curve (Fig. 30.12). This growth pattern can be likened to compound interest at a bank: The more your money increases, the more interest you will get Logistic - As resources decrease ( limited food supply, accumulation of waste products, increased competition, and predation—that prevent populations from achieving their biotic potential. ), population growth levels off and a pattern of population growth called logistic growth occurs. Logistic growth results in an S-shaped growth curve

Question 45

Opportunistic vs Equilibrium species

Answer 45

Opportunistic species - Opportunistic species tend to exhibit exponential growth. The members of the population are small in size, mature early, have a short life span, and provide limited parental care for a great number of offspring (Fig. 30.19a). Density-independent factors tend to regulate the population size, which is large enough to survive an event that threatens to annihilate it. Equilibrium species exhibit logistic population growth, with the population size remaining close to or at the carrying capacity (Fig. 30.19b). Resources are relatively scarce, and the individuals best able to compete—those with phenotypes best suited to the environment—have the largest number of offspring. They allocate energy to their own growth and survival and to the growth and survival of a small number of offspring. Therefore, they are fairly large, are slow to mature, and have a fairly long life span.

Question 46

Two Types of Succession

Answer 46

Ecologists define two types of ecological succession: primary and secondary (Fig. 31.4). Primary succession starts where soil has not yet formed. For example, hardened lava flows and the scraped bedrock that remains following a glacial retreat are subject to primary succession. Secondary succession begins, for example, in a cultivated field that is no longer farmed, where soil is already present. With both primary and secondary succession, a progression of species occurs over time.

Question 47

autotroph vs heterotroph

Answer 47

autotroph Organism that can capture energy and synthesize organic molecules from inorganic nutrients. heterotroph Organism that cannot synthesize organic compounds from inorganic substances and therefore must take in organic nutrients.

Question 48

eutrophication and transfer rates

Answer 48

A transfer rate is the amount of a nutrient that moves from one component of the environment to another within a specified period of time. For example, humans mine phosphate ores and use them to make fertilizers, animal feed supplements, and detergents. Phosphate ores are slightly radioactive; therefore, mining phosphate poses a health threat to all organisms, including the miners.The result is eutrophication, or overenrichment of a body of water, which causes a rapid algal population growth called an algal bloom.

Question 49

Greenhouse

Answer 49

The increased amount of carbon dioxide (and other gases) in the atmosphere is causing climate change to occur. These gases allow the sun’s rays to pass through, but they absorb and reradiate heat back to Earth, a phenomenon called the greenhouse effect.

Question 50

Biosphere

Answer 50

, the biosphere is the zone at the Earth’s surface—air, water, and land—where life exists.

Question 51

Terrestrial ecosystems (7)

Answer 51

Temperature and rainfall define the biomes, which contain communities adapted to the regional climate. The terrestrial ecosystems are called biomes. The major biomes are the tundra, taiga, temperate deciduous forest, tropical grassland (savanna), temperate grassland (prairie), desert, and tropical rain forest. The northernmost biome is the tundra. A permafrost persists year-round and prevents large plants from becoming established. The taiga is a very cold northern coniferous forest, and the tundra, which borders the North Pole, is also very cold, with long winters and a short growing season. Temperate grasslands receive less rainfall than temperate deciduous forests (in which trees lose their leaves during the winter) and more water than deserts, which lack trees. The savanna is a tropical grassland with a high temperature and alternating wet and dry seasons. The tropical rain forests, which occur near the equator, have a high average temperature and the greatest amount of rainfall of all the biomes. They are dominated by large, evergreen, broad-leaved trees.

Question 52

renewable vs nonrenewable energy

Answer 52

Nonrenewable resources, such as fossil fuels and minerals, are limited in supply. Renewable resources, such as solar energy and hydroelectric power, are not limited in supply.

Question 53

Nucleus

Answer 53

nucleus contains the DNA of the cell within the chromatin which also includes mRNA. This messenger RNA takes the code of DNA to ribosomes where the polypetide chains are produced. The nucleus is bound by a nuclear membrane. It also has a nucleolus where rRNA joins with proteins and form subunits of ribosomes which are sent out of the nucleus.

Question 54

Ribosomes

Answer 54

Ribosomes carry out the manufacture of proteins. They are found in both prokaryotes and eukaryotes.In Eukaryotes, some occur freely in the cytoplasm, others are attached to rough endoplasmic reticulum (ER). After polypeptides are modified by the ribosomes they enter the lumen of the rough ER. Both smooth and rough ER have a system of membranous chambers and saccules. Rough ER is covered in ribosomes.

Question 55

Rough ER

Answer 55

Both smooth and rough ER have a system of membranous chambers and saccules. Rough ER is covered in ribosomes. Rough ER both synthesizes (outside, ribosomes) and modifies (inside, lumen) polypeptides forming proteins. Rough ER forms transport vesicles which take proteins to other parts of the cell.

Question 56

Smooth ER

Answer 56

Both smooth and rough ER have a system of membranous chambers and saccules. Smooth ER does not have ribosomes. It synthesizes lipids (phospholipids & steroids). Smooth ER’s function depends on the cell. For example in the testes it produces testosterone and in the liver it detoxifies. It also forms transport vesicles.

Question 57

Golgi Apparatus

Answer 57

The Golgi Apparatus has curved, flattened saccules. It receives transport vesicles. The molecules are then modified as they move between saccules.It’s like a receiving center, it sorts and packages into new transport vesicles.

Question 58

Lysosomes

Answer 58

Lysosomes, produced by the Golgi apparatus are vesicles that digest molecules and portions of the cell. Lysosomes enzymes can ingest the contents of a vesicle that has eaten molecules outside the cell.

Question 59

Vesicles and Vacuoles

Answer 59

Vesicles and Vacuoles are membranous sacs. Vacuoles are larger. Vesicles transport and digest. Vacuoles tend to be more specialized. For example in plants they store substances and protists have large ones for breaking down nutrients,

Question 60

Chloroplasts

Answer 60

Chloroplasts are found in plants and algae and are where photosynthesis occurs. Chloroplasts are much larger than mitochondria, the other energy producing organelle. They are bound by a double membrane. The large space (stroma) contains thylakoids, a mix of disc like stacks and enzymes. The pigments that capture the sun are in the thylakoids and the enzyme that synthesizes the carbohydrate formed by photosynthesis is in the stroma. Chloroplasts have their own DNA and ribosomes.

Question 61

Mitochondria

Answer 61

Mitochondria are much smaller than chloroplasts, only visible under an electron microscope. They also have a double membrane. The inner membrane is highly convoluted and forms christae, which greatly increases the surface area. Mitochondria are the powerhouse of the cell. They produce most of the cell’s ATP. In the matrix is a highly concentrated mixture of enzymes that assists in the breakdown of carbohydrate, which creates ATP synthesis. The matrix also has DNA and ribosomes.

Question 62

Cytoskeleton

Answer 62

Cytoskeleton is a network of protein filaments and tubules from the nucleus to the plasma membrane and provides shape and movement for the cell. It is highly changeable being able to disassemble and reassemble. The cytoskeleton contains microtubules (maintain shape), intermediate filaments maintains the nucleus and plasma membrane. The actin filaments support the cell and projections like microvilli.

Question 63

Centrioles

Answer 63

Centrioles- are short, barrel shaped and composed of microtubules. Not all eukaryotes have centrioles. They may give rise to basal bodies found at the base of flagella and cilia.

Question 64

Flagella and Cilia

Answer 64

Flagella and cilla are whip like projections coming out of the cell. They aid in movement of the cell. They may also move objects around the cell. Flagella are long and undulate. Cillia are shorter and stiffer.

Question 65

Preparatory Reaction

Answer 65

pyruvate breaks down 2 carbon acetyl bound to coenzyme A. Releases carbon dioxide Occurs twice per glucose Occurs in the mitochondria 2nd step in Cellular respiration, after glycolosys. Occurs in the nucleus. The preparatory reaction takes the two pyruvate and breaks them down into 2 carbon acetyl bound to coenzyme A. Oxidation yields both NADH and carbon dioxide.

Question 66

Glycolosys

Answer 66

First step of cellular respiration is glycolysis, which occurs in the cytoplasm of the cell. Glycolys transforms two molecules of pyruvate. Two ATP are gained and NAD+ (coenzyme) is converted to NADH. The next step moves into the matrix of the mitochondria.

Question 67

Citric Acid Cycle

Answer 67

the citric acid cycle is the third step in cellular respiration, which is also in the mitochondria matrix. Oxidation occurs and NADH and FADH2 result, more carbon dioxide is released and 2 ATP are produced per molecule.

Question 68

Electron transport chain

Answer 68

NADH and FADH2 give up electrons to the ETC Energy released is captured to produce ATP by chemiosmosis. Chemiosmosis is the movement of ions across a semipermeable membrane bound structure, down their electrochemical gradient. H20 is released

Question 69

Law of segregation

Answer 69

Mendel- two factors which separate at breeding. of two alleles separate from each other. each gamete has equal chance of containing either allele

Question 70

Law of Independent Assortment

Answer 70

Mendel - traits/”factors” separate independent of each other

Question 71

Autosomal Disorder

Answer 71

Can be dominant or recessive. Genetic disorders carried on the autosomes Polydactylia is an example of a dominant one and cystic fibrosis is an example of a recessive one

Question 72

Interphase

Answer 72

the time when the cell performs its usual functions

Question 73

G1 phase

Answer 73

In the cell cycle during interphase. G1 is the phase before DNA replication. This is a growth phase for the cell, where the cell doubles its organelles. The cell uses internal and external signs to determine whether it moves on to further stages. Some cells never leave this and are said to enter G0 phase. An example is muscle cells.

Question 74

S phase

Answer 74

In the cell cycle, durining interphase, This stands for synthesis and is when sister chromatids are formed

Question 75

G2 phase

Answer 75

The G2 phase during interphase of the cell cycle leads to the onset of mitosis. Proteins needed for cell division are formed. By the end of interphase a pair of centrosomes are outside the nucleus.

Question 76

Prophase

Answer 76

First stage of mitosis. The chromosomes are condensing and contain sister chromatids around a centromere. The spindle is beginning to form outside the nucleus. Then the nuclear envelope breaks down. The centrosomes move to the poles and spindle fibers attach to the chromosomes. Chromosomes move to the poles.

Question 77

Metaphase

Answer 77

2nd stage of mitosis. where chromosomes align at the spindle equator and spindle fibers reach from one pole to the other.

Question 78

Anaphase

Answer 78

3rd stage of mitosis, the sister chromatids separate, becoming daughter chromatids. Each pole receives a set and the spindle poles move apart.

Question 79

Telophase and Cytokinesis

Answer 79

Final stage of mitosis. Tie nuclear envelope begins to form and spindle disappears. Each newly formed nucleus has the same number and type of chromosomes as the parent cell. Cytokinesis leads to the separation of the newly formed cells

Question 80

1st step of natural selection

Answer 80

The members of a population have heritable variations

Question 81

2nd step of Natural Selection

Answer 81

The population produces more offspring than the resources of an environment can support.

Question 82

3rd step of Natural Selection

Answer 82

The individuals that have favorable traits survive and reproduce to a greater extent than those that lack these traits.

Question 83

4th step of Natural selection

Answer 83

Over time, the proportion of a favorable trait increases in the population, and the population becomes adapted to the environment.

Question 84

Law of dominance

Answer 84

Mendel's law of dominance states that in a heterozygote, one trait will conceal the presence of another trait for the same characteristic.

Question 85

Directional Selection

Answer 85

Directional selection occurs when a change occurs to a population over time that favors an extreme genotype. The frequency of the distribution curve shifts in that direction. A changing environment can lead to this type of change. One of three types of selection- directional, stabilizing and disruptive

Question 86

Stabilizing selection

Answer 86

Stabilizing occurs when the intermediate phenotype is selected for. This is the most common. Example is the clutch size of the swiss starling at 4 to 5 eggs, not more or less. Average is most fit.

Question 87

Disruptive selection

Answer 87

Disruptive selection occurs when two or more extreme phenotypes are selected for. This is polymorphism of the same species and typically occurs when there are differences in their habitats. British land snails live in forests and are dark and fields and are light, each an adaptation to camouflage.

Question 88

NAD+

Answer 88

NAD+ is converted to NADH in glycolysis along with two pyruvate.

Question 89

Oxidation in Cellular Respiration

Answer 89

Occurs in the Citric Acid Cycle: Oxidation occurs and NADH and FADH2 result, more carbon dioxide is released and 2 ATP are produced per molecule.

Question 90

carbon acetyl

Answer 90

The preparatory reaction takes the two pyruvate and breaks them down into 2 carbon acetyl bound to coenzyme A. Oxidation yields both NADH and carbon dioxide.

Question 91

Genetic mutation

Answer 91

A cause of microevolution. Genetic mutation rate generally low and neutral but change in environment can make this significant.

Question 92

Gene flow

Answer 92

A cause of microevolution caused by the migration of individuals in a population

Question 93

Nonrandom mating

Answer 93

A cause of microevolution some examples are assortative mating, sexual selection and inbreeding are examples

Question 94

Genetic Drift

Answer 94

A cause of microevolution-Genetic drift refers to changes in the allele frequencies of a gene pool due to chance. Some specific types are the bottle neck effect and the founder effect.

Question 95

Prezygotic Barriers

Answer 95

Prezygotic barriers occur before the formation of a zygote. Examples include habitat isolation, temporal isolation (coming to heat in at different times), behavioral isolation, mechanical isolation and gamete isolation.

Question 96

Postzygotic Barriers

Answer 96

Postzygotic reproductive barriers happen after the formation of the zygote. Examples include: hybrid sterility, (mule), zygote mortality, and f2 fitness (mules that can reproduce but offspring can’t)

Question 97

Allopatric Speciation

Answer 97

A speciation model based on geographic isolation of populations is called allopatric speciation

Question 98

Sympatric Speciation

Answer 98

With sympatric speciation, a population develops into two or more reproductively isolated groups without prior geographic isolation

Question 99

Adaptive Radiation

Answer 99

Occurs after speciation. Adaptive radiation is when many new species evolve from a parent species. Darwin’s finches is a prime example of this.

Question 100

Three types of speciation

Answer 100

Allopatric, sympatric and Adapative.

Question 101

Causes of mass extinction

Answer 101

Continental drift, climate change and meteor impact

Question 102

Five mass extinction time periods

Answer 102

e mass extinctions occurred at the ends of the Ordovician, Devonian, Permian, Triassic, and Cretaceous periods.

Question 103

Four categories of organelles

Answer 103

The four categories are: nucleus and ribosomes, Endomembrane system, vesicles and vacuoles and energy related organelles.

Question 104

Phylogenetic Tree

Answer 104

A diagram that shows common ancestors and lines of descent. Common ancestors are at the bottom. The tree gets more specific as it moves up.

Question 105

Cladogram

Answer 105

A cladogram is a diagram that depicts evolutionary relationships among groups of organisms. The first step in constructing a cladogram is to draw up a table that summarizes the traits of the species being compared. At least one is considered an outgroup. Any trait, such as a notochord, found in both the outgroup and the ingroup is a shared ancestral trait, presumed to have been present in an ancestor common to both the outgroup and the ingroup. Ancestral traits are not shared derived traits and therefore are not used to construct a cladogram. They merely help determine which traits will be used to construct the cladogram. Shared traits are then noted and used to determine how to make the cladogram. Scattered traits are not used.

Question 106

Three domain origins

Answer 106

In the three-domain system, the prokaryotes were recognized as belonging to two groups so fundamentally different from each other that they have been assigned to separate domains, called domain Bacteria and domain Archaea. Domain Eukarya contains kingdoms for protists, animals, fungi, and plants. Systematists have determined that domain Bacteria arose first, followed by domain Archaea and then domain Eukarya

Question 107

Virus structure and replication

Answer 107

Each type of virus always has at least two parts: an outer capsid, composed of protein subunits, and an inner core containing its genetic material, which may be either DNA or RNA. Viruses are specific to a particular host cell because a spike, or some portion of the capsid, adheres in a lock-and-key manner to a specific molecule (called a receptor) on the host cell’s outer surface. Once inside a host cell, the viral genome takes over the metabolic machinery of the host cell. In large measure, the virus uses this machinery, including the host’s enzymes, ribosomes, transfer RNA (tRNA), and ATP, to reproduce itself.

Question 108

Antibiotic resistance.

Answer 108

When an antibiotic is administered, some bacteria may survive because they are genetically resistant to the antibiotic. Over use of antibiotics makes this more common. These are the bacteria that are likely to pass on their genes to the next generation. As a result, the number of resistant bacteria keeps increasing. Drug-resistant strains of bacteria that cause tuberculosis have become a serious threat to the health of people worldwide. ** Directional selection

Question 109

Mutualism: Legume and Bacteria

Answer 109

The bacteria genus Rhizobium invade the roots of legumes, with the resultant formation of nodules. Here the bacteria convert atmospheric nitrogen to an organic nitrogen that the plant can use. This is a form of mutualism.

Question 110

Methanogens

Answer 110

A type of Archaea- Found in anaerobic environments, such as in swamps, marshes, and the intestinal tracts of animals. Those found in animal intestines exist as mutualists or commensals, not as parasites. Methanogens are chemoautotrophs This methane, which is also called biogas, is released into the atmosphere, where it contributes to the greenhouse effect and global warming. About 65% of the methane in Earth’s atmosphere is produced by methanogenic archaea.

Question 111

Halophiles

Answer 111

A type of Archaea- The halophiles require high-salt concentrations for growth (usually 12–15%; by contrast, the ocean is about 3.5% salt). Halophiles have been isolated from highly saline environments, such as the Great Salt Lake in Utah, the Dead Sea, solar salt ponds, and hypersaline soils (Fig. 17.17). These archaea have evolved a number of mechanisms to survive in high-salt environments. They depend on a pigment related to the rhodopsin in our eyes to absorb light energy for pumping chloride and another, similar pigment for synthesizing ATP.

Question 112

Thermoacidophiles

Answer 112

A third major type of archaea are the thermoacidophiles (Fig. 17.18). These archaea are isolated from extremely hot, acidic environments, such as hot springs, geysers, submarine thermal vents, and the areas around volcanoes. They reduce sulfur to sulfides and survive best at temperatures above 80°C; some can even grow at 105°C (remember that water boils at 100°C). The metabolism of sulfides results in acidic sulfates, and these bacteria grow best at pH 1 to 2.

Question 113

Lycophytes

Answer 113

The lycophytes, (horsetails) which evolved around 420 MYA, were among the first plants to have a *vascular system* that transports water and solutes from the roots to the leaves of the plant body. Plants with vascular tissue have true roots, stems, and leaves. The leaves of lycophytes, called microphylls, are very narrow.

Question 114

Mosses

Answer 114

Mosses represent the closest plant link between the green algae and the remainder of the plant kingdom (Fig. 18.2). Mosses are low-lying plants that generally lack vascular tissue and therefore have no means of transporting water, but they do have means to prevent the plant body from drying out and they protect the embryo within a special structure.

Question 115

Ferns

Answer 115

Ferns are well-known plants with large leaves called megaphylls. The evolution of branching and leaves allowed a plant to increase the amount of exposure to sunlight, thus increasing photosynthesis and the production of sugars.

Question 116

Gymnosperms

Answer 116

The next evolutionary event was the evolution of seeds. A seed contains an embryo and stored organic nutrients within a protective coat (look ahead to Fig. 18.10). Seeds are highly resistant structures well suited to protecting the plant embryos from drying out until conditions are favorable for germination. The gymnosperms were the first seed plants to appear, about 360 MYA.

Question 117

Angiosperms

Answer 117

The final evolutionary event of interest to us is the evolution of the flower, a reproductive structure found in angiosperms. Flowers attract pollinators, such as insects, and they give rise to fruits that cover seeds. Plants with flowers evolved between 120 and 140 MYA.

Question 118

4 major tissue types

Answer 118

From the many different types of animal cells, biologists have been able to categorize tissues into just four major types: Epithelial tissue (epithelium) covers body surfaces and lines body cavities. Connective tissue binds and supports body parts. Muscular tissue moves the body and its parts. Nervous tissue receives stimuli and conducts nerve impulses.

Question 119

3 types of neurons

Answer 119

Sensory, motor and interneurons (go between the sensory and motor).