Semester 1 review

Polypeptide

amino acid chain

nucleotide

The definition is the picture->->->->->->->->

Cell Division

Drugs that are used to treat diseases like cancer usually target what cellular process?

Enzyme

protein that speeds up chemical reactions

Active Site

enzymes are specific so only the correct substrate will fit into the enzyme's ___________ site

substrate

molecule that the enzyme works on to build-up or break-down into the resulting product.

Factors that effect how enzymes work

temperature, pH, concentration

catalyst

lowers activation energy for chemical reactions to proceed. Enzymes act as catalyst in biological reactions.

Photosynthetic Equation

6H20 + 6CO2 --> C6H12O6 + 6O2

Chloroplast

organelle found in cells of plants and some other organisms that captures the energy from sunlight and converts it into chemical energy

Reactants of Photosynthesis

6H20 + 6CO2

Products of Photosynthesis

C6H12O6 + 6O2

Photosynthetic Pigments

Chemicals like chlorophyll (in chloroplasts) that absorb light energy and use it to carry out photosynthesis.

ATP (adenosine triphosphate)

Chemical energy source created in cellular respiration that cells use for most of their work.

Autotrophic

An organism capable of synthesizing its own food from inorganic substances, using light or chemical energy. Green plants, algae, and certain bacteria are autotrophs.

Chloroplasts

Organelle that absorbs sunlight and uses it to drive the synthesis of organic compounds from carbon dioxide and water.

Photosynthesis

The process that converts light energy into chemical energy that is stored in glucose or other organic compounds; occurs in plants, algae, and certain prokaryotes.

Chlorophyll

Green pigment located in membranes within the chloroplasts of plants and algae and in the membranes of certain prokaryotes.

6CO2 + 6H2O → C6H12O6 + 6O2

What is the balanced equation for photosynthesis?

Carbon dioxide (CO2)

What provides the carbon atoms that are incorporated into sugar molecules in photosynthesis?

Cancer

What disease is characterized by repeated cell divisions caused by disruptions to the cell cycle

Tumor

Uncontrolled cell division

What might cause a disruption to the cell cycle?

Mutations to a gene that controls the cell cycle

Checkpoints (in G1, G2, and M phase)

What happens throughout the cell cycle that helps the cell to PREVENT disruptions to the cell cycle?

tumor

What do we call the abnormal growth of tissue caused by a disruption to the cell cycle?

malignant cancer

rapidly dividing tumor cells which metastasize

transcription

the process whereby the DNA sequence in a gene is copied into mRNA

translation

the process whereby genetic information coded in mRNA directs the formation of a specific protein at a ribosome

mRNA

messenger RNA; type of RNA that carries instructions from DNA in the nucleus to the ribosome

tRNA

transfer RNA; type of RNA that carries amino acids to the ribosome

rRNA

ribosomal RNA; is a component in the structure of a ribosome

codon

a specific sequence of three adjacent bases on a strand of mRNA that provides genetic code information for a particular amino acid

anticodon

group of three bases on a tRNA molecule that are complementary to an mRNA codon

complementary base pairing

Hydrogen bonding between particular bases.

In DNA, T pairs with A; G pairs with C;

RNA, U pairs with A and G pairs with C

RNA polymerase

An enzyme that links together the growing chain of RNA nucleotides during transcription using a DNA strand as a template.

cytoplasm

the organelles and jellylike fluid inside the cell in which the organelles are suspended

ribosome

organelles at which proteins are synthesized.

nucleus

A part of the cell containing DNA in eukaryotic cells

thymine ... cytosine

In a DNA double helix an adenine of one strand always pairs with a(n) _____ of the complementary strand, and a guanine of one strand always pairs with a(n) _____ of the complementary strand.

After DNA replication is completed, strands produced are "semi-conservative"

each new DNA double helix consists of one old DNA strand and one new DNA strand

anti-parallel

one strand of the DNA double helix runs 3' to 5', the complementary strand runs 5' to 3'

sister chromatids

After replication is complete, the new DNAs, called _________, are identical to each other and joined together at the centromere

passive transport

the movement of substances across a cell membrane without the use of energy by the cell

diffusion

movement of molecules from an area of higher concentration to an area of lower concentration.

concentration gradient

the difference in the concentration of molecules across a distance.

equilibrium

the concentration of molecules will be the same throughout the space the molecules occupy.

osmosis

the process by which water molecules diffuse across a cell membrane.

cytolysis

the bursting of a cell

facilitated diffusion

the transport of substances through a cell membrane along a concentration gradient with the aid of carrier proteins.

carrier protein

a protein that transports substances across a cell membrane.

active transport

the movement of chemical substances, usually across the cell membrane, against a concentration gradient; requires cells to use energy.

endocytosis

the process by which a cell membrane surrounds a particle and encloses the particle in a vesicle to bring the particle into the cell.

exocytosis

the process by which a substance is released from the cell through a vesicle that transports the substance to the cell surface and then fuses with the membrane to let the substance out.

selectively permeable

some materials can pass through while others can not

diffusion

molecules move from an area of high concentration to an area of low concentration

osmosis

diffusion of water molecules across a selectively permeable membrane

passive transport

the movement of materials across a cell membrane without using energy

active transport

the cell must use energy to transport materials across the cell membrane

solute

a substance ex. (sugar or salt) that is dissolved in another substance

solvent

usually a liquid that dissolves another substance ex. water

Gene mutation

Mutations in the sequencing of the DNA. Affects one gene and typically one protein.

Chromosomal mutation

Mutations in part or the whole chromosome. Affects many genes and many proteins.

Point mutation

The change in ONE nitrogen base in the DNA sequencing. Ex: A changes to C

Substitution

Same as point mutation. One base changed to another.

Frame Shift Mutation

An INSERTION or DELETION gene mutation. (Changes the "reading frame" base sequencing by shifting the codon grouping of 3.)

Base deletion

Mutation where one nitrogen base of the DNA is lost and shifts the reading frame. Many amino acids are incorrect.

Base insertion

Mutation where one nitrogen base of the DNA is added and shifts the reading frame. Many amino acids are incorrect.

chromosome deletion mutation

Mutation where a segment of the chromosome (containing one or more genes) is lost. Affects many proteins and genes.

Base Insertion Mutation

Mutation where one or more nucleotides is added to the genetic sequence, often drastically altering the proteins made.

Base Deletion Mutation

frame-shift mutation where a nucleotide is deleted from the genetic material

Substitution Mutation

substitution (point mutation)

What type of gene mutation is show in this image?

insertion (framshift mutation)

What type of gene mutation is show in this image?

deletion (frameshift mutation)

What type of gene mutation is show in this image?

substitution (point mutation)

What type of gene mutation is show in this image?

point mutation (substitution)

What type of gene mutation is show in this image?

DNA

deoxyribonucleic acid

double helix

2 complimentary strands of DNA joined by hydrogen bonds in a twist

A, T, C, G

four nitrogenous bases of DNA

thymine

Adenine (A) pairs with ____

cytosine

Guanine (G) pairs with _____

DNA replication

synthesis of DNA strands which are identical to each other and to the original DNA molecule

DNA polymerase

enzyme that bonds the complementary nucleotides to an open DNA strand. Can also proofread and fix errors in incorrect base pairing.

nucleus

place where DNA storage & replication occurs

RNA

ribonucleic acid

uracil

base that replaces Thymine (T) in RNA

protein

nutrient that carries out MOST of the functions of the cell

e.g. enzymes, hormones, antibodies, cell membrane proteins, haemoglobin, muscle, clotting, collagen ...

nucleotide

one unit of a sugar + phosphate + base

chromatin

long strands of DNA

(when cell NOT replicating)

gene expression

DNA codes for proteins which create the expressed traits of the organism

histone

protein that DNA coils aroound

triplet/codon

3 bases on DNA that code for an amino acid

(or base triplet)

amino acid

subunit that makes up a protein

(20 amino acids - 10 nonessential

i.e. made by human body)