SAMEALIKE STANDING STAYING

GREATER CONCENTRATION LESSER CONCENTRATION diffusion

TWO CRITERIA FOR OSMOSIS: 1.SUBSTANCE MUST BE WATER 2.SUBSTANCE MUST PASS THROUGH A SELECTIVELY PERMEABLE MEMBRANE

GREATER CONCENTRATION LESSER CONCENTRATION GRADIENT

A.solution in which the number of water molecules inside the cell is equal to the number of water molecules outside the cell B. the number of solute molecules inside the cell is equal to the number of solute molecules outside the cell water molecules solute molecules

water molecules solute molecules C. no net movement of water or solute molecules equal

solute molecules and water molecules constantly move into and out of the cell, but the rates of movement are equal a cell in an isotonic solution is a cell in homeostasis! O = water molecules X = solute molecules X X X X X O O O O O O X

PLANT CELL IN AN ISOTONIC SOLUTION water enters the cell at the same rate as it leaves the cell solute enters the cell at the same rate as it leaves the cell normal shape and pressure

A.solution in which the number of water molecules inside the cell is less than the number of water molecules outside the cell; net movement of water is into the cell water molecules greater concentration outside the cell move into the cell

B. the number of solute molecules inside the cell is greater than the number of solute molecules outside the cell; net movement of solute molecules is out of the cell solute molecules move out of the cell greater concentration inside the cell

C. in animal cells, it results in cytolysis (bursting of the cell due to turgor pressure – pressure that exists in a cell due to the presence of water D. in plant cells, it results in wilted plants becoming rigid (due to gain of turgor pressure); presence of the cell wall. prevents cytolysis cytolysis cell membrane breaks

E. in some protists, organelles called contractile vacuoles collect water coming into the cell, then contract, and squeeze the water out of the cell through the cell membrane; prevents cytolysis contractile vacuole collects water coming in and contracts it out of the cell under

PLANT CELL IN A HYPOTONIC SOLUTION water molecules move into the cell solute molecules move out of the cell water molecules are smaller than solute molecules and diffuse more rapidly plant cells swell in a hypotonic solution

X X X X X X X XO O O O O O O O more solute molecules inside the cell solute move out of the cell more water molecules outside the cell water moves into the cell

A.solution in which the number of water molecules inside the cell is greater than the number of water molecules outside the cell; net movement of water is out of the cell water molecules move out of the cell greater concentration inside the cell

B. The number of solute molecules inside the cell is less than the number of solute molecules outside the cell; net movement of solute molecules is into the cell solute molecules move into the cell greater concentration outside the cell

C. results in plasmolysis (shrinking of the cell due to loss of turgor pressure above X X X X X X X O O O O O O O O O more solute molecules outside the cell solute moves into the cell more water molecules inside the cell water moves out of the cell

PLANT CELL IN A HYPERTONIC SOLUTION water molecules move out of the cell solute molecules move into of the cell plant cell loses turgor pressure and shrinks plasmolysis occurs plant wilts

the movement of particles across the plasma membrane without the expenditure of energy Examples of passive transport: 1.diffusion 2.osmosis 3.facilitated diffusion greater concentration lesser concentration

transport protein

greater concentration lesser concentration carrier protein energy the movement of materials across a membrane against the concentration gradient and requiring the expenditure of chemical energy

1. channel proteins – form channels that allow specific molecules to flow through; movement is with the concentration gradient and requires no energy input from the cell channel protein

2.carrier proteins – proteins that change the shape to allow a substance to pass through the plasma membrane; movement is with the concentration gradient and requires no energy input from the cell carrier protein

endocytosis within

process of endocytosis in which fluid materials are engulfed into the cell; forms a vacuole process of endocytosis in which large particles are engulfed into the cell; forms a vacuole to drink to eat

exocytosis out

DIFFUSION RATES NUTRIENTS OXYGEN CARBON DIOXIDE

CELL’S DNA most cells are uninucleated – contain only one nucleus to manage all of the cell’s processes DNA deoxyribonucleic acid “master molecule of the cell”

SURFACE AREA -TO - VOLUME RATIO

1 mm2 mm4 mm surface area = width x width x 6 sides 2 6 mm 2 24 mm 2 96 mm

volume = width x width x width 3 1 mm 3 8 mm 3 64 mm 1 mm2 mm4 mm

6: 1 3 : : 1 best surface area-to-volume ratio 6 / 124 / 8 96 / 64

CELL DIVISIONMITOSIS CHROMOSOMES GENES COLORED BODY

HOMOLOGOUS CHROMOSOMES THE SAME FORM

1. chromatids each of the two identical halves of a chromosome; sometimes called “sister chromatids” 2. centromere the point of attachment of the sister chromatids center portionshare

3. upper arm the part of a chromosome located above the centromere known as the “p” arm (petite) 4. lower arm the part of the chromosome located below the centromere; known as the “q” arm upper arm is always the smallest arm if the centromere is not in the center

5. alleles genes for the same trait that may have differing expressions and located at the same location on sister chromatids shape of nose straight, pug, roman hair color red, blonde, black, brown genetic disease normal, diseased

DNA nucleosome histone continued coiling within supercoil supercoil within chromosome

METACENTRIC

ACROCENTRIC

SUBMETACENTRIC

PROTEINS HEREDITARY UNITS BORN FIRST GENE

CHROMATIN CHROMOSOMES RNA REPLICATION COLORED

HISTONE PROTEINS CHROMATIN THREADS

KARYOTYPE

22 pairs or 44 1 pair or 2 X and X sex chromosomes = female X and Y sex chromosomes = male 23 pairs or 46

PARENT CELL REPLICATION

DAUGHTER CELL PARENT CELL DAUGHTER CELL

continuous sequence of growth and division of a cell, which is controlled by key enzymes

1. period of growth

2. period of division A. mitosis = division of the nucleus B. cytokinesis = division of the cytoplasm

1. the busiest phase of the cell cycle 2. G phase (gap 1 phase) – rapid growth and metabolic activity 1 G phase 1 interphase G = growth

3. S phase (synthesis phase) – DNA synthesis and replication S phase S = synthesis

G phase 2 G phase (gap 2 phase) – centrioles replicate; cell prepares 2 for division

1. first and longest phase of mitosis first

2. chromatin coils and becomes visible as chromosomes chromosomes each chromosome consists of two sister chromatids

3. the nuclear envelope and nucleolus disintegrate disappearing nuclear envelope nucleolus disintegrated

4. centrioles in animal cells start migrating toward opposite poles centrioles

5. in animal cells, the spindle begins to form spindle fibers spindle fibers are microtubules that form from centriole to centriole

1. the second and shortest phase of mitosis middle

2. the doubled chromosomes become attached to the spindle fibers by their centromeres each sister chromatid is attached to its own spindle fiber spindle fibers centromere sister chromatids

3. the chromosomes are pulled by the spindle fibers and begin to line up on the midline, or equator, of the spindle equator one sister chromatid is attached to the spindle fiber at one pole the other sister chromatid is attached to the spindle fiber at the other pole

1. the third phase of mitosis in which the separation of sister chromatids occurs up

2. the centromeres split apart and the chromatid pairs separate from each other the chromatids are pulled apart by the shortening of the microtubules in the spindle fibers chromatids

1. the fourth and final phase of mitosis end

2. chromatids reach opposite poles of the cell pole of the cell pole of the cell chromatids

3. chromosomes unwind and elongate into chromatin 6. the spindle fibers break down and disappear 4. the nuclear envelope reforms around the chromatin 5. the nucleolus reappears

7. cytokinesis occurs 8. two daughter cells are formed division of the cytoplasm two identical daughter cells

interphase prophase anaphase telophase metaphase

interphase prophase metaphase anaphase telophase

1. animal cells – cytokinesis begins during early anaphase when the plasma membrane begins pinching in from the outside to the inside to form the cleavage furrow until the cell divides into two identical daughter cells 2. plant cells – vesicles formed by the Golgi apparatus fuse at the equator of the cell forming the cell plate which grows from the inside to the outside until the cell divides into two identical daughter cells; the cell plate forms into the cell wall

1. division of the nucleus kernelnucleus motion 2. division of the cytoplasm cell

1.guarantees the continuity of life, resulting in the production of two new cells with chromosome sets that are identical to those of the parent cell 2. unicellular organisms remain as single cells – produces two complete new organisms 3. multicellular organisms result in cell growth and reproduction which provides new tissues, organs, and organ systems

1. set of proteins that control the cell cycle 2. proteins that attach to the cyclin and become activated

a malignant growth resulting from uncontrolled cell division Possible causes of cancer: 1. genetic factors – predisposition in the family; genes inherited 2. environmental factors – smoking; air and water pollution 3. viral infections – that damage the genes

HEALTHY LIFESTYLE!!! 1. no cigarette smoking 2.low fat diet 3. high fiber in diet