Bio 103 Exam 2

Energy

Energy

The capacity to do work

Cellular work

includes building complex molecules and moving substances in and out of the cells

Law of Conservation of Energy

Energy cannot be created nor destroyed, it can only change form

Potential energy

Stored energy in the chemical bonds; also called chemical energy

Kinetic energy

The energy of motion or movement

Heat

Transfer of thermal energy generated by random movement of molecules or atoms from one body to another

Autotrophs

Self-feeders that capture and transform the energy of sunlight by photosynthesis

Sunlight, water, carbon dioxide

3 things that autotrophs require:

Heterotrophs

Obtain energy by eating other organisms

Chloroplasts

Where does photosynthesis occur?

Chloroplasts

Organelles present in cells of plants, algae, and some bacteria

Photo step

1. Chloroplast capture energy of sunlight. During process, water is split, releasing oxygen as a by-product

Chlorophyll

A pigment present in the green parts of plants that absorbs photons of light energy

ATP

Energy carrying molecule that is generated when electrons in the chlorophyll become excited

NADPH

captures released electrons; an electron carrier

To replace lost electrons

Why is water split?

Synthesis step

2. Captured energy is used to convert CO2 into glucose

Carbon fixation

ATP and NADPH are used to convert carbon dioxide gas form the air to glucose

Sugar + oxygen

Carbon dioxide + water + sunlight = ? + ?

Light reactions

H+ ions reduce NADP+; and ATP is generated from ADP,

Calvin cycle

makes sugar (G3P) from CO2 using the power of ATP and NADPH made by light reactions

Thylakoid membrane

Where do the Light Reactions occur?

Stroma

Where does the Calvin Cycle occur?

Biofuel

Renewable energy made form living organisms

Fossil fuels

Carbon-rich energy sources

Exergonic reactions

Reactants have more free energy than the products; involves a net release of energy; occurs spontaneously

Endergonic reactions

Reactants have less free energy than the products; require input of energy; does not occur spontaneously

Enzymes

Lower the activations energy and increase probability that a reactions will occur

Aerobic respiration

A series of reactions that converts stored food energy into ATP; occurs in the presence of oxygen

ATP + CO2 + water

In aerobic respiration: Glucose + Oxygen = ? + ? + ?

Glycolysis, Citric acid cycle, Electron transport chain

3 stages of Aerobic Respiration:

Glycolysis

Series of reactions that breaks down glucose into pyruvate; pyruvate enters the mitochondria; makes 2 ATP

2 pyruvate + 2 NADH

In Gylcolysis: Glucose = 2 ? + 2 ?

Cytoplasm

Where does glycolysis occur?

Citric acid cycle

Helps extract energy from food; pyruvate is modified into acetyl-CoA and enters cycle; makes 2 ATP

CO2 + NADH, FADH2

In Citric Acid Cycle: Pyruvate = ? + ? + ?

Mitochondria

Where does the Citric Acid Cycle occur?

Electron transport chain

Electrons passed from NADH down a chain of molecules to oxygen; oxygen accepts the electrons and combines with hydrogen atoms to produce water; make 26-28 ATP

Water + NAD+ + FAD

In Electron Transport Chain: NAPH + FADH2 + Oxygen + ADP = ? + ? + ?

Mitchondria

Where does the Electron Transport Chain occur?

Fermentation

Anaerobic respiration; occurs when oxygen is scarce

Cytoplasm

Where does fermentation occur?

calorie

The amount of energy required to raise the temperature of 1g of water by 1C

Calorie uppercase

Equal to 1,000 calories

Basal, digestion, physical activity, exercise, NEAT

The way we expend energy in percentages: ______ Metabolism: 60% _: 10% __ _______: 30%

• _______: <10%

• ____

Glycogen

A complex carbohydrate which is made up of chained glucose molecules; short-term energy storage

Muscles and liver cells

Where is glycogen located? (2 places)

Triglycerides

Converted fats, amino acids, and sugars; used for long-term energy storage

Fat cells

Where are triglycerides located? (1 place)

Carbohydrates, proteins, fats

__________: 4 Calories per gram __________: 4 Calories per gram __________: 9 Calories per gram

DNA

Hereditary molecule that is passed from parents to offspring that serves as the instruction manual for how build an individual

Nucleus

In eukaryotic cells, where is DNA found?

Chromosome

A single, large DNA molecule wrapped around proteins

46, 23

How many chromosomes do humans have? How many pairs?

Autosomes

Any chromosome that is not a sex chromosome; chromosomes 1-22

Sex chromosome

Determine the sex of the individual

Nucleotides

What is DNA composed of?

Nucleotide

Composed of a phosphate group, a 5-carbon sugar, and one nitrogenous base

T

A must pair with... in DNA

C

G must pair with... in DNA

DNA replication

Natural process by which cells make an identical copy of a DNA molecule

Semiconservative replication

Each newly made DNA molecule contains one original DNA strand and one new strand

Helicase

Enzyme that breaks hydrogen bonds that hold base pairs to unwind the helix

DNA polymerase

Reads the DNA and adds complementary nucleotides using the rules of base paring

Genome

Complete set of genetic instructions encoded in the DNA of an organism

Polymerase chain reaction

Lab technique used to replicate and amplify a specific DNA segment (Full Term)

Denaturation

Heating DNA to separate the two strands

Annealing

Primers guide DNA polymerase to the section of DNA to copy

Extension

DNA polymerase adds nucleotides to elongate the strand using complementary base pairing

Short tandem repeats

Sections of a chromosome in which DNA sequences are repeated; noncoding (Full Term)

Gel electrophoresis

Lab technique that separates fragments of DNA by size

smaller fragments

In Gel Electrophoresis, which size fragments travel farther?

Blood, semen, hair, saliva, fingernails

5 Sources of DNA:

3'-GGGACCCGAGA-5'

5'-CCCTGGGCTCT-3' corresponds to ?

Gene

Section of DNA that contains a nucleotide sequence with instructions to make a protein

Regulatory sequences

On/off switches for genes; determine when a protein is made and how much it makes

Coding sequences

Determine the amino acid sequence of protein which determines its shape and function

Transcription

Copies DNA into complementary mRNA

RNA polymerase

Binds the regulatory sequence of the genes coding region to unwind the DNA strand and expose the coding sequence of the gene

U

With RNA, A must pair with...

UACGACU

If DNA has the sequence ATGCTGA, what is the corresponding sequence of the mRNA?

Translation

Converts the mRNA sequence into amino acid sequence of protein

Ribosome

A complex macromolecule that is the site of protein synthesis

Codons

Groups of three nucleotides

Genetic code

Set of rules dictation which mRNA codons specify which amino acid; code is specific, universal, and redundant

Amino acids

Building blocks of proteins

3D shape

What determines the function of proteins?

Mutation

A change in the nucleotide sequence of DNA

Base substitution

A mutation that changes a single DNA nucleotide

Frameshift

A shift in the entire DNA sequence after the mutation occurs

Recombinant gene

A gene that contains part of different genes that aren't found together in nature

Transgenic

Organisms that have been genetically modified to contain genes from other species

Cell division

The process by which a cell reproduces itself; important for development, growth in size, cell replacement, and healing

Asexual reproduction

Involves inheritance of all genes from one parent; offspring are identical to the original cell or organism

Sexual Reproduction

Involves inheritance of unique set of genes from two parents; offspring are similar to parents, but show variations in traits

Interphase

Preparatory phase of a cell cycle; includes G1, S, and G2

G1 phase

The cell grows and makes extra cytoplasm

S phase

DNA replication occurs; each chromosome is replicated

Sister chromatids

Two identical DNA molecules made in the S phase

Centromere

Specialized region on the chromosome where sister chromatids are joined