Unit 4 Review AP Biology

[rayyanfb]

Thank you so much, this video was incredibly helpful!! For those studying on a time crunch, here's a summary of the points discussed in the video:

Cells communicate by cell to cell contact
Local signaling: short distance messages \
Local regulators target cells in the vicinity of the signal emitting cell. Communication over short distance
long distance signaling (example being hormones)

Signal perception
>
Intracellular signal transduction
>
Cellular response

All cells are composed of cells
Organisms come from preexisting cells
Structural and functional unit is cells
Prokaryotic cells: archaea, bacteria
Eukaryotic cells: bigger, membrane bound organelles

Signal transduction: attaches to receptor on membrane that activates signal transduction pathway and a response in the cell.
Protein modification GDP-GTP
Ligand attaches
Relies on relay protein

Phosphorylation cascade also results in protein modification
Kinase transfers phosphate groups and adds it. Results in activation and activates protein and activates the next cell in the cascade. Signal is amplified.

Relies on a second messenger that passes on the message
Relies on G PROTEIN to cause transduction.
Part that is outside: extracellular domain
Intracellular domain of protein receptor changes shape.

Ligand gated ion channel
Neurotransmitter attaches to receptor and opens protein
Mechanically gated: physically opens


Ultimate response is cell growth and division, can result in apoptosis (programmed cell death)
Mutations can affect cell pathway


Organisms use feedback mechanisms to respond to internal and external stimulus
Negative feedback loop aims to return organism to setpoint or homeostasis
Positive feedback amplifies the response to a stimulus and takes it farther away from setpoint/homeostasis.

Mitosis: 46 chromosomes start and result in 2 diploid cells 46 chromosomes
Meiosis: starts with 46 ends with 23 chromosomes 4 haploid daughter cells

G1: cellular contents besides chromosomes duplicate
S: 46 chromosomes is replicated
G2: cell double checks duplicates chromosome for error and repairs

G0 cell cycle arrest where it cannot divide. Stays in G1 forever until further notice

Growth repair and asexual reproduction

Cell cycle regulation 4.6

To ensure the cell is progressing correctly through cell cycle

In G1, first damage checkpoint is conducted. If DNA is damaged, there is pause for repair
In g2 replication quality is monitored.
In M checkpoint, makes sure all spindle fibers are attached so both cells have all daughter chromosomes

Cyclin and cyclin dependent kinases regulated. Cyclin dependent kinases are constant in cell cycle but only active in presence of cyclin.
When they attach it becomes active. It is the signal for replication to begin.
P53 halts cell division and prevents reaching G1 checkpoint. Prevents cancer. Cd inhibitor.

[machi]

i just wanted to say i love your unit review videos so much! my teacher never makes study guides or tells us what to study for tests, she just tells us to look over the entire unit which is often hundreds of google slides long. your videos are so thorough and your explanations are so easy to follow. you are the reason why im surviving ap bio right now, so thank you!

[kiwikivi]

AP bio in 2 days; this video was really helpful for studying and review! Thank you!

[xxcuddlepandaxx]

Ap Bio exam in 5 days, big RIP














thank you chegg

[maggtse]

Thank you for this playlist I really needed this so badly THANK YOU😭🙏🙏🙏🙏🙏

[ethanwho_]

how can 46 chromosomes be duplicated when there's only chromosomes when you start mitosis where the dna condenses into