FINAL REVIEW BIOLOGY

pretty important stuff

Autrotroph

An organism that makes its own food.

Heterotroph

An organism that feeds on others.

Formula for photosynthesis

6CO2 + 6H2O \------\> C6H12O6 + 6O2

Formula for cellular respiration

C6H12O6 + 6 O2 -\> 6CO2 + 6H20 + ENERGY (ATP)

Catabolic reactions

Breakdown of molecules to release energy.

Anabolic reactions

Synthesis of larger molecules from smaller ones.

Catalyst

A substance that increases the speed of a reaction, without being changed or used up in the reaction.

Enzyme

A biological catalyst.

Activation energy

Energy needed to start a reaction.

Enzyme-substrate complex

A temporary complex formed when an enzyme binds to its substrate molecule(s).

Competitive inhibition

A substance that resembles the normal substrate competes with the substrate for the active site.

Non-competitive inhibition

A molecule can bind to another part of the enzyme that is not the active site, this can seriously disrupt the normal arrangement of bonds holding the enzyme in shape, changing the shape of the active site.

3 variables that influence enzyme activity

pH, temperature, and concentration of the enzyme.

Aerboic

Process that requires oxygen.

Anaerobic

Process that does not require oxygen.

3 stages of cellular respiration

Glycolysis, Krebs Cycle, ETC

Glycolysis

The first stage of cellular respiration is when a molecule of glucose is broken into 2 pyruvate molecules and 2 NADH molecules. Produces 2 ATP molecules; anaerobic: found in the cytoplasm.

Krebs Cycle

The second stage of cellular respiration is when pyruvic acid is broken down into carbon dioxide, 6 NADH molecules, and 2 FADH molecules. Produces 2 ATP molecules; aerobic: found in mitochondria. Takes pyruvates and makes more energy

Electron Transport Chain

The third stage of cellular respiration; is aerobic: is found in mitochondria. A sequence of electron carrier molecules (NADH and FADH) is used to transport electrons and make NAD+

Why does glycolysis have to occur before the Krebs Cycle?

Glycolysis is the first step in the breakdown of glucose to extract energy for the rest of cellular metabolism.

For each turn of the Krebs cycle, what is produced that can immediately be used to power cell activities?

ATP

How does the cell use the NADh and FADH2 produced in the Krebs Cycle.

Used in ETc to make large amounts of ATP.

NAD+

Electron carrier involved in glycolysis.

NADH

An energy-carrying coenzyme produced by glycolysis and the Krebs cycle. carries energy to the electron transport chain, where it is stored in ATP.

How is NAD+ converted to NADH?

When NAD+ takes an electron from glucose, it becomes NADH.

Enzyme vs. Coenzyme

While enzymes are proteins, coenzymes are small, nonprotein molecules that help facilitate enzyme activities.

FADH2

A molecule that stores energy for harvest by the electron transport chain.

How much ATP does cellular respiration generate?

36-38 molecules of ATP per molecule of glucose.

Fermentation

Process by which cells release energy in the absence of oxygen.

Alcholic fermentation

Anaerobic process whereby enzymes break down glucose into ethanol and CO2 and transfer energy to ATP.

Lactic acid fermentation

The conversion of pyruvate to lactate with no release of carbon dioxide.

What is the formula for photosynthesis?

6CO2 + 6H2O \------\> C6H12O6 + 6O2

mesophyll

The ground tissue of a leaf, sandwiched between the upper and lower epidermis and specialized for photosynthesis.

Stomata

Small openings on the underside of a leaf through which oxygen and carbon dioxide can move

Chloryphyll

A molecule (pigment) in chloroplasts that absorobs most of the energy from light

Carotenoids

An accessory pigment, either yellow or orange, in the chloroplasts of plants. By absorbing wavelengths of light that chlorophyll cannot, carotenoids broaden the spectrum of colors that can drive photosynthesis.

light-dependent reactions

reactions of photosynthesis that use energy from light to produce ATP and NADPH

Light Independent Reactions (Calvin Cycle)

A set of reactions in photosynthesis that do not require light; energy from ATP and NADPH is used to build high-energy compounds such as sugar; also called the Calvin cycle. CO2 is needed to make sugar.

Thylakoid

A flattened membrane sac inside the chloroplast, used to convert light energy into chemical energy.

Photosystem 1

a light reaction in which ATP and NADPH are formed (comes 2nd)

Photosystem 2 (PS2)

Splits water into electrons, protons, and oxygen.

NADP+

carrier molecule that transfers high-energy electrons from chlorophyll to other molecules

NADPH

An electron carrier involved in photosynthesis. Light drives electrons from chlorophyll to NADP+, forming NADPH, which provides the high-energy electrons for the reduction of carbon dioxide to sugar in the Calvin cycle.

carbon fixation

Carbon dioxide enters the chloroplast via the stomata and is "fixed" into organic molecules. CO2 combines with RuBP and then this immediately splits into 2 PGA molecules. Rubisco causes this.

Reduction

ATP and NADPH covert PGA intoG3P (a 3 carbon sugar). NADPH donates electrons to this process and so it is called "reduction"

Regeneration

Some G3P go to make glucosemid cycle while the others "recycle" back to makeRuBP again and start the Calvin Cycle over. This step requires ATP- In total, 1 G3P needs 3 CO2- 1 Glucose needs 18 ATP and 12 NADPH

End Results

The two sets of photosynthetic reactions work together—the light-dependent reactions trap the energy of sunlight in chemical form, andthe light-independent reactions use that chemical energy to producestable, high-energy sugars from carbon dioxide and water.In the process, animals, including humans, get food and an atmospherefilled with oxygen.

Factors affecting photosynthesis

temperature, light intensity and the availability of water.

Why do cells reproduce?

growth, repair, replacement

asexual reproduction

A reproductive process that involves only one parent and produces offspring that are identical to the parent.

sexual reproduction

A reproductive process that involves two parents that combine their genetic material to produce a new organism, which differs from both parents

chromsome

Structural unit of genetic material consisting of double stranded DNA and proteins

how many chromsomes do humans have

46 (23 pairs)

What is the role of chromsomes in cell division?

They allow DNA to be copied

Eukaryotic chromosomes

More DNA/multiple chromosomes, DNA coils around histone proteins, chromosomes help genetic seperation.

Prokaryotic Chromosomes

Lack a nucleus. DNA molecules found in the cytoplasm and contain a single chromosome.

diploid cell

A cell containing two sets of chromosomes (2n), one set inherited from each parent.

What is a typical somatic cell for humans?

Diploid

haploid cell

A cell that has only one representative of each chromosome pair.

Chromatin

Substance found in eukaryotic chromosomes that consists of DNA tightly coiled around histones

sister chromatids

Identical copies of a chromosome; full sets of these are created during the S subphase of interphase.

Centromere

Area where the chromatids of a chromosome are attached

Why is the cell cycle

It allows DNA to be duplicated

Interphase

Cell grows, performs its normal functions, and prepares for division; consists of G1, S, and G2 phases

G0

a resting stage of the cell cycle in which DNA replication and cell division stop

G1 phase

The first gap, or growth phase, of the cell cycle, consisting of the portion of interphase before DNA synthesis begins.

S phase

The synthesis phase of the cell cycle; the portion of interphase during which DNA is replicated.

G2 phase

The second growth phase of the cell cycle, consisting of the portion of interphase after DNA synthesis occurs.

daugher cell

Identical to parent cell (genetically) 1/2 size.

Prophase

Chromosomes become visable, nuclear envelop dissolves, spindle forms

metaphase

Chromosomes line up in the middle of the cell

Anaphase

Phase of mitosis in which the chromosomes separate and move to opposite poles of the cell

Telophase

After the chromosome seperates, the cell seals off, Final Phase of Mitosis.

Cytokinesis

division of the cytoplasm to form two separate daughter cells

Cytokinesis in animal cells

Cell membrane is drawn inward until the cytoplasm is pinched into two nearly equal parts

Cytokinesis in plan

Cell membrane too rigid, cell plates forms instead

Spindle

Fanlike microtubule structure that helps separate the chromosomes during mitosis

Role of proteins in cell cycle

Regulate it

bengin tumor

Cells in the mass that remain together and do not spread from the area of local growth, harmless

malignant tumor

An abnormal tissue mass that can spread into neighboring tissue and to other parts of the body; a cancerous tumor.

binary fission

A form of asexual reproduction in single-celled organisms by which one cell divides into two cells of the same size

Meiosis vs. Mitosis

-Meiosis has 2 cell divisions, mitosis only has one

-Meiosis creates 4 daughter cells, Mitosis only 2

-Meiosis creates genetically diverse offspring, Mitosis does not

Autosome

Any chromosome that is not a sex chromosome

crossing over

Process in which homologous chromosomes exchange portions of their chromatids during meiosis.

Diploid

2 sets of chromosomes

Fertilizaiton

fusion of male and female gametes

Gamete

sex cell

homologous chromosomes

Chromosomes that have the same sequence of genes and the same structure

Karyotype

A display of the chromosome pairs of a cell arranged by size and shape. Normal karyotypes have 22 autosomes and 1 pair of sex chromosomes.

Meiosis 1

reproduction process that halves the \# of chromosomes and results in diploid cells

Meiosis II

the second phase of meiosis consisting of chromatids separating, along with the two diploid cells splitting in two

Prophase 1 (crossing over)

Chromosomes become visible; nuclear envelope breaks down; crossing-over occurs.

Metaphase 1

A spindle forms and attaches to each chromosome in the tetrad.

Anaphase 1

Homologous chromosomes separate

Telophase 1

2 daughter cells are formed, each daughter cell contains only one chromosome of the homologous pair.

Prophase 2

The duplicated chromosomes and spindle fibers reappear in each new cell.

Metaphase 2

Centromeres of chromosomes line up randomly at the equator of each cell.

Anaphase 2

Sister chromatids separate and move to opposite poles