sb1:students will analyze the nature of the relationships between structures and functions in living...

SB1:Students will analyze the nature of the relationships between

structures and functions in living cells.

.

Explain the role of cell organelles for both prokaryotic and

eukaryotic cells, including the cell membrane, in maintaining

homeostasis and cell reproduction.

Name the 3 parts of the Cell Theory?

• 1) Cell is the basic unit of life• 2) All organisms are composed of

cells• 3) All cells come from pre-existing

cellsCell Theory

Rap

What characteristics are needed to consider something alive?

• 1) Require food for energy• 2) Use energy to maintain homeostasis• 3) Respond to stimuli• 4) Grow and develop• 5) Reproduce similar offspring• 6) Ability to pass genetic information• 7) Made of cells

What is the difference between a prokaryote and a eukaryote?

• Prokaryote-No membrane bound organelles. Only bacteria are considered prokaryotes. pg.72• Eukaryote- Contains membrane

bound organelles, including a true nucleus.

Cell Comparisons

How are cells different?• Size: Cells must be small for diffusion.

The closer the surface Area/Volume ration the more diffusion. Shape: Fig 4-2. Long, Flat, Branching, etc.

• Type of organelles and the number of each kind. (Red blood cells have no nucleus, Animal cells have no cell wall.)

• Different types of cells have different needs therefore different structures.

StemCell

Differentiation

What is a stem cell?

What is an Organelle?

• Part of a cell that performs a job. Like an organ does a job for the body organelles do the same for a cell.

Prokaryotes vs Eukaryotes and Eukaryotic organelles

Eukaryotic organelles

Which organelles are found in plant cells but not in animal cells?

• Plastids such as Chloroplast- capture solar energy for photosynthesis

• Cell Wall- Adds structure and support to the cell

• Plants also have Central vacuoles for storing water then animal cells. Classzone

Animal Vs.Plant

Define the following organelles: Golgi bodies, Mitochondria, Nucleus,

Ribosome, and Vacuoles.

• Golgi bodies / apparatus- package and distribute lipids and proteins (UPS Store…go go golgi!)

• Mitochondria- powerhouse of the cell, transforms energy (ATP)

Definitions continued…

• Nucleus- contains DNA which controls cellular activities• Ribosomes- rRNA produce proteins,

found on the rough ER or in the cytoplasm as free ribosomes.• Vacuoles- store substances such as

water.

Define the following organelles:Smooth Endoplasmic Reticulum (ER), Rough ER,

• Smooth Endoplasmic Reticulum (ER): Make Fats such as steroids.• Rough ER: Contain Ribosomes.

Package and ship proteins made on Ribosomes.

Organelles Continued

• Lysosome: Contain Digestive enzymes. Think SOS…

• Nucleolus: Ribosomes (rRNA) and other RNA are synthesized. In the nucleus.

Great Lysosome

Short Movie

Define the following organelles

• Flagella: Whip like structure made of microtubules. Few in number and long.

• Cilia: numerous short hair-like structures. Also made of Microtublules.

Flagella and Cillia Video Clip

Very Good!

In the plant cell, in which cell part does cellular respiration occur?

• A) • B)• C) • D)• Answer: A Mitochondria

Organelle Review

Link

Organelle Self-Quiz

Review: Which of the following is a characteristic of all living things?

• A) Cellular Structure• B) Nervous System• C) Chlorophyll• D) Hemoglobin

• Answer: A

Review: What is homeostasis?

• Maintenance of internal equilibrium • Example: Body to returning to

normal temperature (98.7) after a fever.

Explain how enzymes function as catalysts:

• .

Why are Proteins Most structurally & functionally diverse group?

• Function: involved in almost everything – enzymes (pepsin, DNA polymerase)– structure (keratin, collagen)– carriers & transport (hemoglobin, aquaporin)– cell communication• signals (insulin & other hormones) • receptors

– defense (antibodies) – movement (actin & myosin)– storage (bean seed proteins)

How are Proteins structured?

– monomer = amino acids• 20 different amino acids

– polymer = polypeptide• protein can be one or more polypeptide chains

folded & bonded together• large & complex molecules• complex 3-D shape

RuBisCO

hemoglobin

H2O

Sickle cell anaemia

I’mhydrophilic!

But I’mhydrophobic!

Just 1out of 146

amino acids!

What is Metabolism?• Chemical reactions of life– forming bonds between molecules• dehydration synthesis• synthesis• anabolic reactions

– breaking bonds between molecules• hydrolysis• digestion• catabolic reactions

That’s why they’re calledanabolic steroids!

Examples of Metabolic Processes dehydration synthesis (synthesis)

hydrolysis (digestion)

+

H2O

+

H2O

enzyme

enzyme

What is the difference between exergonic and endergonic? Where are they used?

• Some chemical reactions release energy– exergonic– digesting polymers– hydrolysis = catabolism

• Some chemical reactions require input of energy– endergonic– building polymers – dehydration synthesis = anabolism

digesting molecules= LESS organization=lower energy state

building molecules= MORE organization=higher energy state

Too much activation energy for life• Activation energy– amount of energy needed to destabilize the

bonds of a molecule– moves the reaction over an “energy hill”

Not a match!That’s too much energy to exposeliving cells to!

glucose

What Factors Affect Enzyme Function?

• Enzyme concentration• Substrate concentration• Temperature • pH• Salinity• Activators• Inhibitors

catalase

What happens as we increase Enzyme concentration?

enzyme concentration

reac

tion

rate

What’shappening here?!

Factors affecting enzyme function

substrate concentration

reac

tion

rate

• Substrate concentration – as substrate = reaction rate• more substrate = more frequently collide with enzyme

– reaction rate levels off• all enzymes have active site engaged• enzyme is saturated• maximum rate of reaction

How do we Reduce Activation energy?

• Catalysts– reducing the amount of energy to

start a reactionPheeew…that takes a lotless energy!

reactant

product

uncatalyzed reaction

catalyzed reaction

NEW activation energy

What is a Catalyst?• So what’s a cell got to do to reduce

activation energy?– get help! … chemical help… ENZYMES

G

Call in the ENZYMES!

What is an Enzyme? • Biological catalysts – proteins (& RNA) – facilitate chemical reactions

• increase rate of reaction without being consumed• reduce activation energy• don’t change free energy (G) released or required

– required for most biological reactions– highly specific

• thousands of different enzymes in cells– control reactions

of life

What are the properties of enzymes?

• Reaction specific– each enzyme works with a specific substrate • chemical fit between active site & substrate– H bonds & ionic bonds

• Not consumed in reaction– single enzyme molecule can catalyze thousands or

more reactions per second• enzymes unaffected by the reaction

• Affected by cellular conditions– any condition that affects protein structure• temperature, pH, salinity

Induced fit model• More accurate model of enzyme action– 3-D structure of enzyme fits substrate– substrate binding cause enzyme to change

shape leading to a tighter fit • “conformational change”• bring chemical groups in position to catalyze

reaction

How does it work?• Variety of mechanisms to lower activation

energy & speed up reaction– synthesis• active site orients substrates in correct position for

reaction– enzyme brings substrate closer together

– digestion• active site binds substrate & puts stress on bonds

that must be broken, making it easier to separate molecules

What Factors Affect Enzyme Function?

• Enzyme concentration• Substrate concentration• Temperature • pH• Salinity• Activators• Inhibitors

catalase

What is a Buffer?

• Chemical substances that neutralizes small amounts of an acid or base added to a solution.

• Why are these important to your body?

Ph Scale• Measured on grams of Hydrogen (H+)– pH of 1= 1g of H+, pH of 2= .01g of H+

• Acid: form hydronium ions (H+)– pH of less than 7 ( 1 to 6.9)

• Base: form hydroxide ions (OH-)– pH of more than 7 (7.1 to 14)

• Acid + Base: salt & water, the solution is neutral with a pH of 7. – NaOH + HCL = H2O + NaCl with a pH of 7

Atoms• Three major parts. –Protons: Positive Charge. Inside Nucleus–Neutrons: Neutral Charge. Inside Nucleus: – Electrons: Negative Charge. Outside Nucleus• 2 electrons in first shell• 8 electrons in the second shell• Eight is Great! Will not React with other

atoms.• If the outer shell is not full it will react.

Combining Chemicals

• Compound: When two or more different elements combine.

• Hydrogen Bond: H2O – When hydrogen bonds with another atom. Creates a polar

molecule.• Covalent bond: CO2

– When atoms on the same side of the chart (same size) bond. Share electrons.

• Both Hydrogen and Covalent bonds form molecules, ionic bonds do not.

Ionic/ Covalent

Bonds

Periodic Table

Bonding

Combining Chemicals continued

• Ionic Bonds: When atoms on different sides of the chart (different size) bond. Steal electrons. Create Ions. Make teeth and bones.

• Ion: Charged particle either negative or positive. NaCl = table salt

• Free Radical: Electrically charged ion with an unpaired electron in its outer shell.

Identify the function of the four major macromolecules.

• .

Organic Compounds: C-H

• Lipids: Fats long term energy storage

–Have very few oxygen atoms–Saturated fats: All C bonded to H.

Lard, and butter.–Unsaturated fats: C is double

bonded to itself. Oil.

Lipids

Organic Compounds: C-H

• Carbohydrate: fast energy–made of Carbon, Hydrogen, and

Oxygen. 1:2:1 proportion. Sacchar = sugar•Monosaccharides:C6H12O6,

glucose, fructose, & glactose•Disaccharides: 2 sacchar’s:

Sucrose, table sugar•Polysaccharides: Many sacchar’s:

Cellulose (wood) and starch.

Carbohydrates

Organic Compounds:All organic compounds contain Carbon.

• Protein: the working molecule –50 or more Amino Acids make a

protein–Types of Proteins•Muscle• Enzymes: Control chemical reactions

and can be re-used like a key in a lock• Hair

Protein

Organic Compounds:All organic compounds contain Carbon.

• Nucleic Acids: Genetic Instructions• pg. 37 DNA and RNA–Made of nucleotides: Sugar,

Phosphate, and X• ATP: energy cells run on.

DNA

Explain the impact of water on life processes (i.e. osmosis, diffusion)

• .

Solution

• A mixture in which one or more substances are evenly distributed in another substance.

• Solute: smaller word, smaller thing• Solvent: bigger word, bigger thing

Types of solutions:

• Aqueous Solutions: water is the solvent.• Saturated solutions: no more solute can

dissolve in the solvent.• Concentration: the amount of solute

dissolved in a fixed amount of a solution.

The Importance of Water

• Polar molecule (it has a negative and positive charge.)– Can dissolve both Ionic and Polar-Covalent

molecules• Surface Tension– Cohesion: Sticks to itself.– Adhesion: Like a band-aid. Sticks to stuff

• Capillary Action: Climbs up thin tubes

transpiration

Importance of Water

• Evaporates: Cooling, Water cycle, etc• Resists Temperature Change: Takes a

lot of energy to heat or cool water• Expands as it Freezes.

The plasma membrane only allows certain things to enter and exit the

cell. What is this called?• Selectively permeable membrane or

selectively permeable

What is passive transport? Name and describe the 3 types.

• Passive Transport- movement of substance of substances across the plasma membrane without the use of energy.

Passive Transport

The Three TypesDiffusion: movement of substances

across the plasma membrane from high to low concentration

Osmosis: diffusion of water across the plasma membrane from high to low concentration

Facilitated Diffusion: carrier molecules transport larger substances across the membrane from high to low.

What is active transport? Describe the two major types.

• Active Transport: uses energy and carrier molecules to move substances across the plasma membrane from low to high concentrations (against the concentration gradient)

Active Transport

The two types of Active Transport

•Endocytosis: process by which large particles are brought into the cell•Exocytosis: process by which large particles leave the cell

Endo/Exocytosis

Substances that are too large to be moved across the plasma membrane can be

engulfed through the process of …

• A) Diffusion• B) Endocytosis• C) Exocytosis• D) Osmosis• Answer: B

• Endo= inside, Exo= Outside, cyto=cell, osis= process or action

There are 3 types of solutions a cell can be in.

• 1) Hypotonic• 2) Hypertonic• 3) Isotonic

Hypo/Hyper/Iso

Scroll Down

Hypo/Hyper/Iso Solutions

Red blood cell

Describe a cell in an isotonic solution.

• Iso= the same. The concentration of the solution is the same inside and outside the cell.

• The cell stays the same size. • There is no net movement across the plasma

membrane (things enter and leave the cell at the same rate)

Describe a cell in an hypertonic solution.

• Hyper= above. The concentration of the solution is higher outside the cell than inside.

• The cell shrivels in size.• Water leaves the cell at a faster rate then it

enters.

Describe a cell in an hypotonic solution.

• Hypo= below. The concentration of solutions is lower outside the cell then inside.

• The cell swells or pops in size. hyPO=POP• Water enters the cell at a faster rate than it

leaves

A student is making a model to demonstrate how cells respond to solutions with varying

concentrations of salt and water. She soaked a kidney bean in distilled water until it started to swell. In what kind of solution should she put the swollen

bean to cause it to shrivel?

• A) Acidic• B) Basic• C) Hypertonic• D) Hypotonic• Answer: C