BSC1010L-6 Final Exam Review: Key Concepts and Labs

Enzyme

An enzyme is a catalyst that helps speed up chemical reactions in an organism.

Active Site

The region on an enzyme where the substrate binds.

Specific Substrate

Each enzyme has a specific substrate and therefore active site.

Optimal Environmental Conditions

Each enzyme has specific environmental conditions at which it functions optimally (ex: temperature, pH, presence of inhibitors, etc.).

Rate of Reaction

The rate of reaction is influenced by concentrations of enzyme and/or substrate available.

Catecholase

Catecholase is an enzyme found in potatoes and aids in the reaction between catechol (substrate) and oxygen.

Benzoquinone

When O2 is present, catechol is oxidized and converted to benzoquinone, causing darkening in the potato.

Optimum Temperature

There is an optimum temperature at which the enzyme functions.

Denaturation

When temperature is too high, the enzyme is denatured (the structure of the enzyme breaks down).

Effect of pH on Enzyme Activity

The active site shape can change shape depending on the pH.

Optimum pH

There is an optimum pH at which the enzyme functions.

Enzyme/Substrate Complex

An enzyme/substrate complex is formed when substrate is bound to its enzyme.

Reaction Rate and Enzyme Concentration

Reaction rate will increase as enzyme concentration increases up until the reaction is limited by substrate availability.

Substrate Concentration

If the amount of enzyme is kept constant but the substrate concentration increases, the velocity will increase until it reaches its maximum.

Saturation of Enzymes

Substrate increases no longer speed up the rate of reaction because all enzymes become saturated.

Pectinase

Used applesauce to test the effect of pectinase on juice making. Pectinase creates more juice

Cell Respiration Equation

C6H12O6 + O2 → CO2 + H2O + ATP + Heat.

Glycolysis

Formation of pyruvate (in cytoplasm).

Citric Acid Cycle

Occurs in mitochondria.

Electron Transport Chain (ETC)

Occurs in mitochondria.

Anaerobic Respiration

Cell respiration in absence of O2.

Fermentation

Formation of CO2 and ethanol (plants, some microbes (yeast)) or formation of lactic acid (some microbes, animals).

ATP Production in Anaerobic Respiration

Produces 18 fold less ATP per glucose than aerobic respiration.

Magnesium Sulfate

Activator of glycolysis.

Sodium Fluoride

Inhibitor of glycolysis.

Glucose

Energy source for respiration.

Measuring CO2 Production

Height of bubbles of CO2 after incubation.

Photosynthesis Equation

CO2 + H2O C6H12O6 + H2O + O2

Photosynthesis Dependence

Photosynthesis is light dependent and chlorophyll dependent.

Role of Pigments

Pigments are responsible for absorption of light.

Primary Pigments

Primary pigments in photosynthesis are chlorophyll a and b.

Accessory Pigments

Other accessory pigments (carotenoids and xanthophylls) also absorb light.

Chlorophyll Production in Fall

In fall, chlorophyll production stops and accessory pigments are responsible for most of light absorption.

Paper Chromatography

Paper chromatography separates the pigments in plants.

Pigment Movement in Chromatography

Some pigments move faster up the paper than others, depending on solubility and other factors.

Pigment Adsorption

Pigments adsorbed strongly are more polar and move slower; those adsorbed weaker move faster up the paper, less polar.

Xanthophylls

Yellow band in chromatography represents xanthophylls.

Carotenes

Yellow-orange band in chromatography represents carotenes.

Chlorophyll a

Blue-green band in chromatography represents chlorophyll a.

Chlorophyll b

Yellow-green band in chromatography represents chlorophyll b.

Rf Value

Rf = distance moved by pigment/distance from pigment origin to solvent front.

Spectroscope Function

Spectroscope separates white light into its component colors (appear as a spectrum).

Light Absorption by Chlorophyll

Light not visible through the extract has been absorbed. Blue light is the best light for photosynthesis

Wavelength

The shorter the wavelength, the higher the energy value.

Phenol red

pH indicator that turns yellow in acidic solutions and red in basic solutions.

Uptake of CO2 during Photosynthesis

Phenol red is used to observe uptake of CO2 during photosynthesis by Elodea.

Mitosis

Replication and division of the nucleus of a eukaryotic cell. Diploid cells. Cell production and growth.

Cell cycle

Includes Interphase (G1, S, G2), mitosis (less than 10% of cell cycle), cytokinesis.

G1 phase

Preparation of proteins for mitosis.

S phase

Replication of DNA, chromosomes consist of pair of sister chromatids, attached at the centromere.

G2 phase

Molecules and structures necessary for mitosis are synthesized.

Prophase

Nuclear membrane breaks down, chromosomes become visible, spindle starts to form.

Metaphase

Sister chromatids are attached to spindle and align along the metaphase plate.

Anaphase

Sister chromatids separate and become individual chromosomes, move towards the poles.

Telophase

Chromosomes decondense and nuclear envelopes reform, cleavage furrow separates the 2 cells (animals) or cell plate (plants).

Diploid

Nucleus with 2 of each type of chromosome.

Meiosis

Recombination of parent's genes and production of gametes (sex cells), produces haploid daughter cells (reduction division).

Diploid cells (2n)

All cells in the body except gametes.

Homologous chromosomes

The 2 chromosomes of a pair, each homologue has same loci for the same genes.

Haploid cells (n)

Gametes. during sexual reproduction, 2 gametes fuse to restore original diploid nuclei

each gamete contains 23 chromosomes

Crossing over

Pairing of homologous chromosomes to form a synapse, followed by exchange of genetic information at chiasma. Only in meiosis

Meiosis I

Includes interphase, prophase I, metaphase I, anaphase I, telophase I and cytokinesis.

Meiosis II

Includes prophase II, metaphase II, anaphase II, telophase II and cytokinesis.

Mitosis vs Meiosis

Mitosis produces 2 genetically identical diploid daughter cells; Meiosis produces 4 genetically different haploid daughter cells.

Detergent

Breaks down the cell membrane.

Meat tenderizer

Breaks down proteins (histones) to unravel DNA.

Alcohol

Precipitates the DNA. Found this in the pea juice when mixed with ethanol

Mendelian Genetics

Genes occur in pairs (alleles).

Law of Segregation

Each gamete has an equal chance of possessing either of the pair of homologous chromosomes.

Law of Independent Assortment

Genes on nonhomologous chromosomes will be distributed randomly into gametes.

Genotype

All alleles present in the cell, e.g., Pp.

Phenotype

Physical appearance, e.g., Purple.

Homozygous

Paired alleles are identical, e.g., PP or pp.

Heterozygous

Paired alleles are different, e.g., Pp.

Monohybrid Cross

Involves only 1 trait.

Dihybrid Cross

Involves 2 traits, with a phenotypic ratio of offspring 9:3:3:1.

Incomplete Dominance

Heterozygous genotype results in intermediate characteristics.

Codominance

Both alleles contribute to the phenotype of a heterozygote.

Sex-linked Inheritance

Involves alleles on sex chromosomes and are thus linked to gender.

F1 generation

first generation of offspring

Blood type

determined by antigens on surface of red blood cells. If antigen A or B is present, no antibodies against this antigen are produce

Person with type A blood has antigen A on surface and produces antibodies against antigen B

sex-linked inheritance

All traits previously discussed are produced by alleles on autosomes

Sex-linked inheritance involves alleles on sex chromosomes and are thus linked to gender

XX: female

XY: male

Both male and females can have X-linked traits present

If a male has an X chromosome that carries the recessive allele, the allele is expressed (no chance for masking by a dominant allele on another X chromosome)

widow's peak

Dominant trait for hairline shape.

pigmented iris

dominant

Hitchhiker's Thumb

recessive

dimpled chin

dominant