Bio chapters 6-10 exam 2

The process by which plants, autotrophic protists, and some bacteria use light energy to make sugars and other organic food molecules from carbon dioxide and water.

6 CO2 + 6 H2O ------ light & energy ----> C6H12O6 + 6 O2

light reactions, and the Calvin cycle.

Basically the light (input) strikes chlorophyll a in such a way as to excite electrons to a higher energy state. In a series of reactions the energy is converted (along an electron transport process) into ATP and NADPH. Water (input) is split in the process, releasing oxygen (output) as a by-product of the reaction, and gas (output).

ATP NADPH

chemical energy

essentially the hydrogen that is attached to water.

sugar & other organic molecules (outputs) from carbon dioxide (input).

This occurs in the stroma, which are located in the chloroplast!

A light harvesting unit of a chloroplasts thylakoid membrane and consists of of several hundered ANTENNA molcules, a reaction center chlorophyll. and a primary electron acceptor.

because when a pigment molecule absorbs a photon, one of the pigment’s electrons gains energy and the electron raises from a ground state to an excited state. Because the excited state is very unstable, the excited electron usually loses its excess energy and falls back to its ground state.

because; chlorophyll and the other pigments built into the membranes of grana mainly absorb light in the blue-violet and red-orange part of the electromagnetic spectrum (this part of the light spectrum is most important for photosynthesis). The pigments do not absorb much green light-which is why we see green-it is reflected!

Englemann observed that oxygen-seeking bacteria migrate toward algae exposed to certain colors of light by using a string of cells suspended in water on a microscope slide. He discovered that blue-violet and orange-red wavelengths best drive photosynthesis.

Well, C4 plants actually do close their stomata but are still able to perform photosynthesis thanks to a super helpful enzyme! This enzyme is attracted to CO2 and actually produces a four-carbon compound that shuttles CO2 to the calvin cycle.

Some miraculous plants that have this capability include; corn and sugarcane!

by opening its stomata and allowing CO2 to enter at night! The same enzyme that is found in C4 plants is also found in CAM plants! Here, this enzyme collects the CO2 at night and actually releases it to the Calvin cycle during the day!

Asexual reproduction does not fertilize from an egg and a sperm, instead it inherits all their chromosomes from a single parent.

Single-celled organisms reproduce by simple cell division=clones.

fertilization from a sperm and an egg.

DNA is packed into eukaryotic cells using an elaborate, multilevel system of coiling and foiling resulting in highly condensed chromosomes. A crucial aspect of DNA packing is the association of the DNA with small proteins called histones (found only in eukaryotic cells).

(found only in eukaryotic cells).

Chromosomes contain a single long DNA molecule, typically bearing thousands of genes.

Chromosomes are made up of material called chromatin (a combination of DNA and protein).

Humans have 46 chromosomes.

in mitosis! when you see the doubling of the one chromosome. they are held together by a centromere.

Homologous Chromosomes include the 'pairing' up of the maternal chromosome with the paternal chromosome (which is usually observed in meiosis 1).

Most of the cell cycle is spent in interphase, typically interphase last for 90% of the cell cycle. While in interphase a cell performs normal functions within the organism, doubles everything in the cytoplasm, increases supply of proteins, increases the number of many of its organelles, grows in size, and most importantly chromosomes duplicates.

by the fusion of many vesicles produced in the golgi apparatus.

The chromosomes double and the two sets become two seperate nuclei.

they pair!

they yield with a haploid set of chromosomes.

• -Interphase
• -Prophase I
• -MEtaphase I
• -Anaphase I
• -Telophase I
• -Meiosis II
• -Anaphase II

Homologuous pairs stick together in pairs which equals four chromatids (they CROSS OVER =)

Homologuous pairs LINE up!

the shsiter chromatids finally seperate which = four haploid daughter cells!!

• Glycolysis,
• citric acid cycle
• electron transport

The splitting of sugar. Here a six-carbon glucose molecule (input)is broken in half by enzymes, and two molecules of pyruvic acid (output) are eventually formed. 2 ATP are created from direct synthesis. 2 NADH are created. The enzymes that are used here are located in the cytosol.

Pyruvic acid, that is left over from glycolysis is “prepped” and becomes acetic acid (input) so that it may be used in this cycle. The acetic acid is broken down all the way to CO2 (output). 2 ATP are created from direct synthesis. 2 NADH are created The enzymes used here in this process are dissolved in the fluid within the mitochondria.

Here an electron transport chain is used that captures the energy released from the “fall” of electrons. The energy is then used to pump hydrogen ions across the inner mitochondrial membrane. Potential energy is stored in the ions because ions become more concentrated on one side of the membrane than on the other because they are being pumped by the electron transport chains. ATP synthase occurs, and basically proteins use the energy of a hydrogen concentration gradient to make 34 ATP (output). 6 NADH & 2 FADH2 are created.

Redox reactions.

transfer electrons from fuel molecules to NAD+, which forms NADH. 38 ATP total are produced over all throughout the process of cellular respiration -usually, there may be a few more or less molecules.

energy is given off. This energy is used to generate ATP from ADP!

Anaerobic (without oxygen) harvest of energy

Fermentation occurs in both human muscle cells and microorganisms (like fungi and bacteria! Think yeast!) .

when muscle cells consume ATP faster than O2 can be supplied for cellular respiration, they regenerate ATP by fermentation. (notice the importance of ATP!) The waste product under these conditions is lactic acid, that's what our muscles produce when they are sore from being used! Notice that the ATP yield per glucose during fermentation is much lower than the yield of ATP in cellular respiration.

occurs when a haploid sperm cell fuses with a haploid egg cell.

TWO homologous sets of chromosomes. Humans as well as most plants are diploid.

A single chromosome set. IT has only one member from each homologuous pair. The haploid number in humans is 23.

the member of a chromosome pair fail to separate at anaphase. Gametes with abnormal number of chromosomes are the result. This can lead to an abnormal number of sex chromosomes. The most common is an extra X in males a condition called Klinefelter syndrome which causes men to have smaller testis and are sterile.

A severely deranged cell cycle control system. They divide excessively, but they also exhibit other kinds of bizarre behavior.

Radiation therapy exposes to high-energy radiation which disrupts cell division. Chemotherapy causes cells to stop reproducing.

Varities for which self-fertilization produced offspring all identical to the parent. Mendel worked until he found true-breeding in the plants.

Parent plants differ in only one characteristic.

A sperm or egg carries only one allele for each inheritied chracteristic because the two members of an allele pair segregate (seperate) from each other during the production of gametes.

Crossing parental variety

The inheritance of one characteristics has no effect of another.

A mating between an individual of unknown genotype and a homozygous recessive individual. The possible results of Mendel's pea plants could either be All purple or 1 purple:1 white. After reviewing the results of the offspring one could determine the genotypes of the parents. Using a punnet square would help this determination.

shows the history of a trait in a family and allows geneticists to analyze human traits

most disorders are recessive. Individuals who carry the recessive allele are carriers of the disorder and seem totally normal.

genes are located at specific positions on chromosomes and that the behavior of chromosomes during meiosis and fertilization accounts for inheritance patterns.

inherited together as a set.

During meiosis, crossing over between homologous chromosomes shuffles chromosome segments in the haploid daughter cells which produce a new combination of alleles!

A linkage map is used by geneticists to show where genes are located on chromosomes - like a map of genes!

A linkage map is used by geneticists to show where genes are located on chromosomes - like a map of genes!

sex linked gene. The X chromosome contains many more genes than the Y; therefore, most sex linked genes unrelated to sex determination are found on the X chromosome.

A chromosome not directly involved in determining the sex of an organism; in mammals, any chromosome other than X or Y.

Te process of two consecutive nuclear divisions in the formation of germ cells in animals and of spores in most plants, by which the number of chromsosomes ordinarily is reduced from the diploid number found in somatic cells to the hapoid.

DNA and RNA are both nucleic acids, which consist of long chains (polymers) of chemical units (monomers).

Large molecules consisting of many identical or similar molecular units which are called monomers. these are joined together in a chain.

a chemical subunuit that serves as a building block for polymers.

Nucleotides are joined by a sugar-phosphate backbone.

A C G T

A C G U

Deoxyribose

Deoxyribose is a sugar which makes up the 'backbone' for the structure of DNA.

ribose.

the five carbon sugar component of RNA. it is a monosacharide.

A functional group consisting of a phosphorous atom covalently bonded to four o2 atoms.

Typically 2.

Typically 1.

Carbohydrates and proteins are monomers that build nucleic acids.

Each nucleotide consists of a nitrogenous base, a sugar and a phosphate group.

When a cell reproduces, a complete copy of the DNA must pass from one generation to the next. Watson and Crick's model for DNA suggested that DNA replicates by a template mechanism, with each DNA strand serving as a mold, or template, to guide reproduction of the other strand).

Replications results in two daughter DNA molecules, each consisting of one old strand and one new strand. (The parental strand untwists as its strands separate and the daughter DNA rewinds as it forms).

DNA replication begins at specific sites on a double helix, called origins of replication, proceeding in both directions creating replication bubbles.

Enzymes that make the covalent bonds between the nucleotides of a new DNA strand

DNA functions as the inherited directions for a cell or organism, it dictates the production of a polypeptide.

the synthesis of proteins in two stages

Transcription and translation.

transfer of genetic information from DNA into an RNA molecule

transfer of information from RNA into a protein

linear sequence of nucleotide bases.

• A typical gene consists of 1000s of nucleotides
• * A single DNA molecule may contain thousands of genes

Substitutes Uracil (U) for thymine (T). (Remember! - U pairs with A)

• Initiation
• elongation
• termination

• * “start transcribing” signal is a nucleotide sequence called a promoter.
• * RNA polymerase attaches to the promoter
• * RNA nucleotides are linked by RNA polymerase activity.

• * RNA grows longer
• * RNA strand peels away from the DNA template

• * RNA polymerase reaches a sequence of DNA bases called a terminator
• * Polymerase detaches from the RNA and the 2 DNA strands rejoin

• * RNA processing includes:
• * Adding a cap and tail
• * Removing introns (stays inside) and splicing exons (exits the nucleus) together to form messenger RNA (mRNA)

* Conversion from the nucleic acid language to the protein language.

• * mRNA carrying the message (order of the amino acids in the protein to be made) (makes 3 types of ribosomes)
• * energy
• * Enzymes to move the molecules around
• * Ribosomes to catalyze the peptide bond formation
• *Transfer RNA (tRNA) carrying the amino acids

anticodons

amino acids

is a molecular interpreter for RIBOSOMES

• * Coordinate the functions of mRNA and tRNA
• * made of two protein subunits and ribosomal RNA (rRNA)
• * fully assembled ribosome holds tRNA and mRNA for use in translation

• initiation
• elongation
• termination

• a) mRNA molecule binds to a small ribosomal subunit, then an initiator tRNA binds to the start
• codon (AUG on mRNA)
• b) large ribosomal subunit binds, creating a functional ribosome

• a) Codon Recognition: anticodon of an incoming tRNA pairs with
• the mRNA codon at the A site of the ribosome.
• b) Peptide bond formation:
• * polypeptide leaves the tRNA in the P site and attaches to the amino acid on the tRNA in the A
• site acids
• * ribosome catalyzes the bond formation between the two amino acids

• * P site tRNA leaves the ribosome
• * tRNA carrying the polypeptide moves from the A to the P site

a mutation

• * Elongation continues until:
• * ribosome reaches a stop codon
• * completed polypeptide is freed
• * ribosome splits into its subunits

Mutations can change the amino acids in a protein.

* Large regions of a chromosome or a single nucleotide pair

• * base substitution: replacement of one base by another
• * nucleotide deletion: loss of a nucleotide
• * nucleotide insertion: addition of a nucleotide

• Although mutations are often harmful, they are the source of genetic diversity, which is
• necessary for evolution by natural selection

• * Viruses exhibit some, but not all, characteristics of living organisms.
• * Are not cellular and cannot reproduce on their own.
• * Viruses possess genetic material in the form of nucleic acids (either DNA or RNA)

Viruses that attack bacteria

• Many copies of the phage are made within the
• bacterial cell, and then the bacterium lyses (breaks open)

• phage DNA inserts into the bacterial chromosome
• * bacterium reproduces normally, copying the phage at each cell division

• * Stunt growth and diminish plant yields
• * Spread throughout the entire plant
• * Viral plant diseases have no cure; best prevented by producing plants that resist viral infection

• * common causes of disease
• * may have RNA or DNA genomes
• * Some animal viruses steal a bit of host cell membrane as a protective envelope.

are subcellular infectious particles that are small circular RNA molecules that do not encode proteins

Are other subcellular infectious particles that are misfolded proteins that somehow convert normal proteins to the misfolded prion version.

• * Mad cow disease and Scrapie in sheep and goats
• * Chronic wasting disease in deer and elk
• * Creutzfeldt‐Jakob disease in humans

They are all sub-cellular infectious particles that can cause diseases, but they are structurally different.