AP Bio Cell Communication and Cell Cycle (Unit 4)

Communication is important for organisms and involves transduction of … or … …. from other cells, organisms, or the environment

stimulatory or inhibitory signals

Unicellular organisms detected and respond to .. …

environmental signals

Unicellular organisms use .. .. to locate a suitable …

cell communication, mate

Unicellular organisms use cell communication to .. … … in response to changes in … availability

adapt metabolism rates, nutrient

Unicellular organisms use cell communication to make their … known to other members of their species –– phenomenon called .. ..

numbers, quorum sensing

movement of organism in response to stimulus and can be positive (towards stimulus) or negative (away)

taxis

innate behavior responses/instincts

taxes

Movement in response to chemicals

chemotaxis

Cells of multicellular organisms need to communicate with each other to …. … of … as a whole

coordinate activities of organisms

An example of chemotaxis is when bacteria control their flagella to….

avoid poison

Cell signaling can be short range, which affects … …. …

only nearby cells

Cell signaling can also be long range, which affects … …. …

cells throughout organism

Cell signaling can be done through … ….

signalling molecules

Signaling molecules are called …

ligands

Ligands bind to ….

receptors

By binding to receptors, ligands triggrr a response by ….. …. … of the … …

changing the shape of the receptor protein

Process by which an EXTERNAL signal is transmitted to the inside of a cell

Signaling transduction

The first step of signal transduction is for the signaling molecule … to … …

binds to specific receptor,

The second step of signal transduction is for the …. of … … …

activation of signal transduction pathway

The third and final step of signal transduction is is the production of a … ….

cellular response

….. signal molecules can diffuse across plasma membrane

hydrophobic

An example of a hydrophobic signal molecule is is …-… .. …

cholesterol-based steroid hormone

Hydrophobic signaling molecules … … inside cell and often travel to NUCLEUS where they … … …

bind receptors, regulate gene expression

For signaling molecules that cannot enter the cell (hydrophilic), a … … … is required

plasma membrane receptor

Open or close an ion channel binding a particular ligand

ligate-gated ion channel

Membrane receptor with an enzymatic active site on the cytoplasm

Catalytic receptor

This membrane receptor does not act like an enzyme, but instead binds different version of G-protein

G-protein-linked receptor

G-protein-linked receptor causes activation of … … within cells

secondary cells

…. is known as universal hunger signal because it is the second messenger of hormones epinephrine and glucagon, causing energy mobilization

cAMP

Signal transduction in eukaryotic cells involve many … and … …

steps and complex regulation

… … … are helpful to AMPLIFY a signal

Signal transduction cascades

Signal transduction cascades are helpful in turning response … or …

on or off

Signal transduction cascades can lead to important changes in … .. and .. …

gene expression and cell function

Signal transduction pathways influence how cells … …. …. …

respond to their environment

Pathways may cause change to … … and … …

gene expression and cell function

Changes in gene expression and cell function which make change a cell’s …. or … …

phenotype or cause apoptosis

All things have a “… …” they try to maintain

Steady state

Structures and process within living things are sensitive to things like …, …, … etc

temperature, pH, pressure

The set of conditions under which living things can successfully survive under is called ….

homeostasis

The body is constantly working to maintain homeostasis by ….. … and responding appropriately

taking measurements

Depending on adverse conditions that the body is facing, the body … …

responds accordingly

Responses to maintaining homeostasis are controlled by …. and …. …. …

negative and positive feedback pathways

… … …. inhibits the process by shutting down the pathway to conserve …

negative feedback pathways, energy

… … …. stimulates the pathway to … even more of whatever it is making

positive feedback pathways, make

Positive feedback pathways are seen in … …

fruit ripening

Plants do not have a … system

nervous

However, plants can produce .. … found in animal nervous systems

several proteins

Some proteins found in animal nervous systems that plants can produce are … …

neurotransmitter receptors

Plants can generate … signals in response to … …

electric, environmental stimuli

…. …. are common in plants and can help …. … … to …. ….

light receptors, link environmental cues to biological processes

An example of linking environmental cues to biological processes is … …. or timing of …

seed germination, flowering

Some plants use … to communicate with nearby plants

chemicals

An example of plants using chemicals to communicate with nearby plants are when:

wounded tomatoes produce volatile chemical as an alarm signal

Our body makes so so many cells every day because of … …

cell division

Cell division is a very … portion of the cell cycle

small

The life cycle of a cell is known as the ….

cell cycle

The cell cycle is divided into two periods: … and …

interphase and mitosis

Mitosis is the same thing as … …

cell division

The time span between one cell division to another (passing time soooo boring lol) (inter – BETWEEN)

interphase

Interphase is when the cell has not yet started to …

divide

Biologists sometimes call interphase the “… …”

resting stage

During interphase, the cell carries out its … …

cellular activities

All … and …. that are necessary are produced during interphase

proteins and enzymes

Interphase can be divided into three stages: …, …, …

G1, S, G2

The most important part of interphase is … phase

S

S phase is when cell …. its … …

replicates its genetic material

First thing a cell needs to do before undergoing MITOSIS is …. all of its ….

duplicate, chromosomes

Duplicating all of a cell’s chromosomes is important because it contains all of organism’s “…” (DNA)

blueprint

During interphase, every single …. in the ….. is ….

chromosome in the nucleus is duplicated

Chromosomes are ..-…. like a bowtie

single-stranded

After REPLICATION, one chromosome becomes …

two

the two chromosomes come together and form an X-shaped … ….

sister chromatids

Chromatids are held together by a structure called a …

centromere

Each chromatid is kind of a chromosome still I guess, but because they are attached, they are called …. instead

chromatids

In order to be called a chromosome, each chromosome needs to have its own ….

centromere

Once the chromatids separate, that is when they will become ….

chromosomes

During G1 and G2 phase, cells perform … ….

metabolic reactions

During G1 and G2 phase, cells also produce …., …, and …

organelles, proteins, and enzymes

During G1, the cell produces all the …. required from DNA replication

enzymes

We can associate “G” with …

growth

The three phases (G1, S, G2) are …. by … and …. …

regulated by checkpoints and special proteins

Special proteins that regulate the three phases are called … and …-… ….

cyclins and cyclin-dependent kinases

Control mechanisms that make sure cell division is happening PROPERLY in eukaryotic cells

Cell cycle checkpoints

Cell cycle checkpoints are control mechanisms make sure cell division is … … in … cells

happening properly in eukaryotic

Checkpoints monitor the cell to make sure … … ….. to …. through cell cycle

it is ready to progress

In eukaryotes, checkpoint pathways function mainly at … …. (between each one)

phase boundaries

Checkpoint pathways are an example of an … .. … … inside cells

important cell signaling pathway

If the cell is not ready to progress, the cell cycle checkpoint …. ….

stops progression

If DNA damage is so severe it cannot be repaired, the cell can under go …. (programmed cell death)

apoptosis

A CDK, is also known as

cyclin-dependent kinase

when a cell loses control of the cell cycle

cancer

mutated genes that induce cancer

oncogene

genes that produce proteins that prevent the conversion of normal cells into cancer cells

tumor suppressor genes

Mitosis is when the cell divides into … …. … … …

two genetically identical daughter cells

order of phases of mitosis

prophase, metaphase, anaphase, telophase

First signs of prophase is the … of the …

disappearance of the nucleus

Prophase happens when ….. condenses into ……

chromatin condenses into chromosomes

During prophase, …. …. form.

spindle fibers

During metaphase, the chromosomes … … … …

line up along middle