Bio exam 2

Chap 4

Cytoplasm

Everything in the cell except the nucleas

Nucleas and what kind of membrane

Holds all genetic informatiom, has a double membrane (double phospolipid bilayer)

Nuclear pores (aka nucleopores)

regulates what enters & leaves the nucleus

Nucleolus

where ribosomes are synthesized

Multinucleated cells and what kind

cells with MORE THAN 1 nucleus

Ex: skeletal muscle cells, osteoclasts (bone cells)

Anucleate cells and what kind

cells withOUT a nucleus - red blood cells (RBCs)

Cytosol

The liquid component of the cytoplasm in which organelles are suspended (like jelly) and metabolic reactions occur.

Organelles

Structures that perform specific functions within a cell

Centrioles

Paired cylinder made of microtubules that help spindle fiber formation (for when

cell divides)

Ribosomes

Small spheres made up of 60s & 40s subunit (in eukaryotic cells) Also attached with rough ER, and is site of protein synthesis

Endoplasmic reticulam

made of network of membranes; flattened sacs/tubules. (STD)

Synthesizes molecules, Transports substances, Detoxifies chemicals, Releases calcium

Golgi Body

(Golgi apparatus) is membranous sacs; flattened & stacked, that modify, sort, & package proteins; synthesize lysosomes

Lysomes

powerful digestive enzymes with low pH, acid hydrolases, it is the “stomach”; digestion; break

down intracellular components & extracellular substances (recyclying)

mitochondria

has a double membrane, OUTER membrane = smooth & straight, INNER membrane = cristae (folds) Is where ATP is synthasized

cytoskeleton and order, and examples

network of fibers of protien in the cytosol, provide structure + hold organelles in place
smallest to largest - Microfilaments 🡪 intermediate filaments 🡪 microtubules

Microtubules:

Cilia – short, hair-like projections; helps move stuff along cell’s surface

Flagella – long; moves entire cell

Prokaryotic Cells and Peptidoglycans

Unicellular, 1 circular chromosome in nucleoid region, No nucleus ,No organelles
Peptidoglycans in a cell wall – a structural polymer consisting of sugars and amino acids

What gram stains purple/blue

Positive

What gram stains pink

negative

Eukaryotic Cells

comlpex cells with true nucleus
Animal cells have only plasma membrane (cell membrane)
Plant cells have both cell wall and plasma membrane

Somatic cells and division

Body cells (all cells except germ and gametes)
23 pairs, 46 chromosomes
Divide by mitosis

Germ cells and division

Specialized cells in the gonads (ovaries and testes) that produce gametes (eggs and sperm)
Germ cells also have 23 pairs
Divide by meiosis

gametes

Egg and Sperm
only 23 individual chromosomes, no pair
Zygote has 46

3 stages of DNA replication

1. Initiation - strands of DNA unwind and expose their bases

2. Elongation - free nucleotides come in to pair with the exposed bases

3. Termination - replication ends… 2 identical copies of the DNA molecule

Karyotypes

Organized pic of all 46 chromosomes

Autosomes

1-22 non sex chromosomes

Sex chromosomes

23rd pair
XX both long - female
XY one long, one short - male

Trisomy 21

Down syndrome
extra 21 chromosome
flattened face and nose,

Trisomy 18

extra 18 chromosome
wierd skull, mishaped ears, short neck

3 possible things can happen to a cell

Remain alive & functioning withOUT dividing (“G0 phase”)

Grow & divide

Die

Apoptosis

genetically programmed cell death; “cell-suicide”

Necrosis

tissue death due to injury or lack of blood flow

Chapter 5

ATP is what

adenosine triphosphate - a nucleotide (nucleic acid)
combination of sugar (ribose), phospate group, and nitrogen base (adenine)
ATP - 3 phosphate

How does ATP get released

With hydrolysis, the terminal phosphate breaks down releasing energy, making it a diphosphate

Aerobic respiration and yield

where cells use oxygen to break down nutrients like glucose and turn them into usable energy (ATP), releasing carbon dioxide and water as waste
Yields 36 ATP

Anaerobic respiration and yield

A metabolic process where cells break down sugar molecules to produce energy (ATP) without using molecular oxygen

Yields 2 ATP

Glycolysis, location, needs oxygen?

breakdown of 1 glucose (6 carbon molecule) into 2 pyruvates that still have 6 carbon
Genarates 4 ATP, uses 2, outcome 2
Occurs in cytosol
Anaerobic phase of cellular respiration (doesn’t require O₂)

Yield of glycolysis

2 pyruvate
2 ATP

2 NADH

Prep step, location, needs oxygen?

Needs Oxygen to start
Pyruvate enters mitochondria- converted into 2 Acetyl CoA

Krebs cycle and yield

Acetyl CoA breaks into Co2 and H2O
NAD+ and FAD pick up H and electrons and take them to ECT

Yields 2 ATP and 2 CO2

Electron Transport Chain ETC, location

Inner mitochondrial membrane
Start with H and electrons
The e- jumps from pump to pump, making it push out H+ into the intermembrane space

H+ builds up so much that it creates a gradient, allowing it to passively flow back into the matrix through the ATP synthase

Using this energy, a phosphate group is added to ADP, creating ATP (phosphorylation)

The e-, H+, and O2 come together to form H2O

ETC yield

H2O

32 ATP

Other nutrients than glucose for Aerobic resp

Sugars :

Glycogen 🡪 if there is enough ATP, glucose can be strung together to form glycogen for storage

Sucrose 🡪 another way of storing glucose

Protein 🡪 if starvation response is activated

Lipids :

Cholesterol 🡪 made from Acetyl CoA

TGs 🡪 can be made and broken down by this process

Chapter 6

What makes up genetic information of a cell?

The sequence of nucleotides in DNA (A T C G) Adenine, Thymine, Guanine, and Cytosine

Transcription and location

the enzyme RNA polymerase both unwinds (pries open) the DNA double helix and makes a copy (synthesizes a complementary RNA strand) from the DNA template
In nucleus

translation and location

RNA strand serves as the code for which amino

acids are strung together to eventually form a

protein
In the ribosome/ cytoplasm

Process of Translation

Initiation
The mRNA enters the ribosome.

The ribosome finds the start codon, AUG.

A tRNA brings the first amino acid, to match AUG.

2: Elongation

More tRNAs bring amino acids to the ribosome.

Each tRNA matches its anticodon to a codon on the mRNA.

The ribosome joins the amino acids together with peptide bonds.

The chain gets longer and longer

3: Termination

The ribosome reaches a stop codon.

The amino acid chain is released.

The chain folds and may be processed to become a working protein.

Genes

segments of DNA that encode for functional proteins

RNA

Single-stranded nucleic acid

• 5-carbon ribose sugar

• Uracil (U) instead of thymine (T)

Introns

non coding trascript of mRNA

Exons

coding regions of mRNA

Start Codon and AA

AUG - methionine

Anti codon

opposite of the A C G T

The Wobble effect

The wobble effect means the third letter can match flexibly, so one tRNA can match more than one codon.