Ap biology (teacher TikTok)

cell theory

• all organisms are composed of cells

• cells are the structural and functional unit of all living things

• they come form pre-existing cells

prokaryotic cell

bacteria and archaea

• no nucleus, lack membrane bound organ eels, less complex and smaller

eukaryotic cell

plants, animals protists fungi

• nucleus, complex inetrwokign organ eels, complex larger

• (we hold onto prokaryotic cells)

ribosomes

found in both eukaryotic and prokaryotic cells

• made of 2 subunits, protein and rRNA

• function - produces preotins based on dna/rna sequence

• cells have MANY of these

plasma membrane

structure- phopholid bilayer with embedded proteins

regulate what enters and leaves cell

memerbane preotins help

cytosol

structure - semifuiled solution comspoed of water and inorganic and organic molecules

holds other organelles in place. enzymes in cytoplasm aid in chemical reactions

• just the fluid into cell

cytoplasm

cytosol and everything else in the cell liek the organelle

eukaryotic cell evolution

nucleus evolved by cell embrace unfolding on itself

membrane wrapped itself around dan to protect it

endosymbiotic theory

mitochondria and chloroplasts are merabne bound organelles that were engulfed by eukaryotic cells years ago.

mitochondria has double embank

has ribosomes

has its own dna

both divide in an asexaul fashion simairlt o bacteria

nucleus

circular, found near center

contains and protects the dna

nucleolus

dark region white nucleus that creates ribosomes ( some parts)

nuclear envelope

double membrane found around nucleus

nuclear probes - holes in the nuclear envelope

endomembrane system

• Nuclear envelope

• endoplasmic reticulum - rough and smooth er

• Golgi body

• several types of vesicles

• lysomes/ peroxisomes

• plasa memrabne

Network of internal membranes within eukaryote

work together to produce, modify, and transport lipids and proteins

Proteins and lipids are synthesized in the ER, transported in vesicles to the Golgi apparatus for modification, and then packaged into new vesicles to be sent to lysosomes, the plasma membrane, or secreted outside the cell.

endoplasmic reticulum

completed structure of membrane channels

physically connected to the nuclear envelope

rough er and smooth er

rough er

ribosomes

• produce proteins that they are going to alter fold int tier lumen and send to smooth er for later transport go Golgi body

• protein produced are extracellular proteins or membrane bound preotions ( going to be in memorable or outside of the cell)

smooth er

• counted to nuclear envelope and rough er. No ribosomes

• produces lipids, breaks molecules down sends vesicles to Golgi body

• excrete and send off vesicles form outer portion form smooth er

vesicle

memorable bound organelle, contains materials

• ups of cells

• transport materials around the cell

• has its own membrane

• transports from smooth er to Golgi body

Golgi body

stack of curved saccules (flattened vesicles)

receives filled vesicles for er, modifies and ships proteins and lipids around the cell

packaged and send to bunch of different locations

membrane bound organelles

lysosomes

peroxisomes

lysosomes

• membrane bound vesicles, produced by the Golgi body

• contain digestive enzymes

• they destroy non-functioning organelles, invading pathogens(virus causing), other contents of cell

• break things down in a cell

peroxisomes

• memorable bound organelles containing enzymes

• help break fatty acids and dangerous chemicals

• oxidases inc ell convert free racial h and o to hydrogen peroxide

• Peroxisomes are organelles that break down harmful substances and fatty acids using oxygen.

• They produce and break down:

  👉 hydrogen peroxide (H₂O₂)

  H₂O₂ is toxic

  Peroxisomes convert it into:

  water (H₂O)

  oxygen (O₂)

vacuoles

memorable sacs, larger than vessels, store substances like water and food

function - storage container of the cell

plant cell = larger

animal cell = smaller

chloroplast

double memorable - filled with pigments

location of photosynthesis, use solar energy to synthesize carbohydates

mitochondria

double emmrabne smaller then chloroplast

location of cellular respiration, break down carbohydrates to produce ATP

plants organelles

• large central vacuole

• chloroplasts and mitochondria

• cell wall

• rectangular shape

• no lysosomes because -

• LSO:

  • breaks down waste

  • recycles materials

👉 So it acts like a lysosome + storage unit combined

animal organelle

many small vacuoles

mitochondria

lysosomes

circular or irregular

cytoskeleton - cell wall

• made out of carbohydrates and protein

• maintains shape and protects cell

cytosketltoon

• network of protein fibers found inc ell

• maintain cell shape and assist with movement within cell

microfilaments

actin fibers consisting of 2 chains of actin monomers

structural support, movement

microtubules

hollow cylinders composed of protein call tubulin

helps with structure of cell creates tracks for motor proteins help with cell division

membrane structure

• all cells have membrane which serves as barrier between extracellular and intracellular area

• memorable made of 2 layers of phospholipdis and proteins

• cholesterol - lipids that helps make plasmas membrane mroe flexible (less rigid)

• fluid mosaic model

integral protein

proteins that are permanently embedded within bilayer of membrane

peripheral protein

located on top of membrane can attach and detach

aquaporins

channel preotins that allow water to pass though more easily

can nonpoalr mollies cross easily

yes

can polar molecules pass though membrane

no they need energy to transport

can ions pass

no

smaller and unchanged non polar molecules

yes they can move though memabne easily

water move though membrane

While water can cross the bilayer directly via osmosis, it is slow; aquaporins allow for rapid flow.

transport protein

responsible for transferring molecules into and out of cell (active= energy/ATP / passive= no energy)

Channel proteins form open, hydrophilic pores for fast, passive transport of specific ions or water (e.g., aquaporins).

Carrier proteins bind specific solutes, changing shape (conformational change) to move them across, which is slower but can enable active transport.

enzymatic proteins

proteins that facilitate metabolic reactions

• enzyme found within in membrane

• bonded together or broken apart in reaction

anchor protein

attachment points for cytoskeleton and extracellular matrix

receptor protein

area on pertain recognizes molecules when attached cellular response occurs

• signal transduction

cell recognition protein

functions as cell markers for immune and other systems

flags for cells

junction proteins

functions to anchor or communicate with other cells

protein connected together

desmosomes

connections hold cells together

made though cytoskeleton

hold cells together where tissues stretch

tight junctions

memrbna proteins attach to each other create watertight surface

gap junction

location where water and ions travel though

helps with cell commutation

simple diffusion

movement of molecules for high to low

• gasses and nonpoalr molecules

facilitated diffusion

transport of molecules across membrane though channels/carrier proteins

channel - don’t change structure of protein

carrier - change structure of protein

osmosis

diffusion of water across permeable membrane

• high to low concentration

hypotonic solution

solutions cause cells to swell or burst due to intake of water

hypo = water in

hypertonic solution

solution cause cells to shrink due to water leaving cell

water out

• solution has higher solute concentration compared to another solution

isotonic solution

even amount of water inside and out

plasmolysis

cytoplasm of cell thinks due to osmosis

active transport

requires energy

• against concentration gradient

protein pump

membrane preotins use tap to pump molecules against concentration gradient

example; sodium potassium pump

endocytosis

portion of plasma membrane fuses around substance that enters the cell

exocytosis

secretes substances out of cell by fusing with plasma membrane

this and endocytosis helps deliver neurotransmitters between synapses of nerve cells

autocrine

cell targets itself

example. leaving yourself a reminder to complete soemthing later

cell to cell- juxtracrine

membranes that are touching have merabne preotins the help communication

• tunnel

short distance

commcunaiton of molecules, creates response in other cells

• no onncetion

• not touching but short distance

paracrine

cell secret signaling molecules to near by cells

synaptic

stimulation of nerve cells by neurotransmitters

• like snapchat goes to receiver and then goes away

long distance

longer distance or large number of cells

endocrine

example. organs create hormones that travel throughout Boyd via the circulatory system

ligand

chemical molecule taht bond with protein

can’t pass though membrane

receptor

membrane preotin taht bod with ligand

secondary messenger

internal protein taht relay message

3 stages

reception

transduction

response

reception

ligand binds to the septic receptor which will change its shape

ligand interaction change receptor shape - changes function

transduction

reception carried through relay of secondary messengers into celll

• each step eitehr change shape of protein or active it in some way

response

cell will respond in some way.

example; making protein, making mroe energy entering mitosis, going though apoptosis

each response septic to taht type of cell

single pathways

saem signal can trigger differs response deepening on receiving cell

• each cell has different set of secondary messenger proteins taht create different response

kinase

transfers phosphate groups form ATP to other molecules

phosphates

remove phosoalte groups form proteins

phosphorylation cascade

series of kinases add phosphate to the next one in line, activating it, and sending the signal to the target