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Unit: Cells
Sections: Function of Life, Structure of Life, and Protists
Key Words: cell, cytoplasm, organelle, cell nucleus, cell membrane, cell wall, vacuole, chloroplast, organism,
photosynthesis, DNA, mitochondria, ribosome, prokaryotic cell, eukaryotic cell, tissue, organ, organ system, population,
community, ecosystem, asexual reproduction, sexual reproduction
Essential Questions: (by section)
Function of Life
-
What are the life processes performed by cells?
What are the functions of the organelles in plant and animal cells?
How do the functions of individual cells compare with those of organisms?
Structure of Life
-
What are cells and why are they important?
What structures do most cells have in common?
How do animal cells and plant cells differ?
How do cells in unicellular and multicellular organisms differ?
-
What is a protist?
How do scientists classify protists?
Where on Earth can protists be found?
How do protists affect the lives of other organisms?
Protists
Function of Life
Parts of a cell and function
-
Cytoplasm – gel material, allows for nutrient transport and cushions organelles
Cell membrane – protective outer covering of cell, double layer, allows molecules to pass in and out
Cell nucleus – “brain” of the cell, where genetic material (DNA) is found
Ribosome – Protein generators of the cell
Mitochondria – “powerhouse” of the cell, where cellular respiration occurs
Vacuole/Vesicle – storage organelle, in plants is the largest (stores water – turgor pressure - and other
nutrients)
Golgi bodies – External “UPS” system, packages materials for transport out of the cell
Lysosomes – “Lysol” of the cell, helps break down older worn out parts
Cell wall – in plant cells only, rigid structure, helps with plant form
Endoplasmic Reticulum (ER) – Internal “UPS” system, packages materials for transport within the cell
Chloroplasts – “solar collectors” that contain chlorophyll (green pigment) to help with photosynthesis
Chart – www.docstoc.com
Synthesis of
chemicals
necessary for
life
Respiration
Excretion of
wastes
Nutrition
Movement
Regulation
and response
to stimuli
Growth
Cell
Processes
Reproduction
Structure of life
Cell Theory
1.
2.
3.
4.
All living things are made up of cells.
All cells come from pre-existing cells by division (fission, mitosis)- no such thing as spontaneous generation.
Cells contain hereditary info passed on to other cells by division.
All energy flow (metabolism) of life occurs within cells.
Prokaryotic
Eukaryotic
•no membrane around DNA (no nucleus)
•single-celled organisms
•most have cell wall
•go through fission (reproduction) - identical copy
•ex. Bacteria cells
•membrane around DNA
•have distinct membranes around organelles
•has a nucleus
•more complex organisms
•multi-celled organisms
•goes through mitosis (reproduction) - identical copy of DNA
PROTISTS
• Eukaryotic
• PLANTLIKE: Phytoplankton
Algae Euglenoids Diatoms
Dinoflagellates
ANIMAL-LIKE (protozoans)
amoebas zooflagellates
ciliates
• Eukaryotic unicellular
organisms
• autotrophic
(plantlike/producers) or
heterotrophic (animallike/consumers)
fungus-like (decomposers)be
plant-like or animal-like, or a
decomposer
• May take in other
protists/bacteria as food
source
• can infect host (parasitic)
causes illness/death
What is a
protist?
How do
we classify
protists?
How do
they affect
living
things?
Where can
they be
found?
• found mostly in water/moist
areas;
can be fresh or saltwater
• adaptations allow for movement:
float with currents, flagella whiplike tail, psuedopods cytoplasmic foot extentions
cilia - hairlike extensions
surrounding the cell
Unit: Reproduction and Growth
Sections: Asexual Reproduction, Sexual Reproduction, Mendel and Heredity, Factors that Influence Human Growth and
Development
Key Words: reproduction, asexual, offspring, meiosis, mitosis, regeneration, budding, fission, cell division, spores,
DNA, bacteria, clone, gene, sperm, egg, pollination, stigma, anther, ovum, chromosome, heredity, trait, dominant,
recessive
Essential Questions: (by section)
Asexual Reproduction



How do organisms reproduce asexually?
How is asexual reproduction different from sexual reproduction?
How similar are organisms that are produced through asexual reproduction?
Sexual Reproduction
-
How are gametes involved in sexual reproduction?
How do plants reproduce sexually?
How does sexual reproduction lead to species diversity?
Mendel and Heredity
-
What is heredity and who first proposed it?
How do organisms inherit traits from their parents?
How do scientists predict which genes as organism will inherit?
Why are some physical traits more common than others?
How do human select for certain traits in some organisms?
Asexual
Sexual
no joining of
gametes(sex cells)
combining of
gametes (sex cells)
involves 1 parent
2 parents involved
makes an identical
copy of itself (clone)
allows for
variations/diversity
of traits
Asexual
•Fission - hereditary material duplicates and moves to opposite ends of cells, cell
splits (bacteria)
•Budding - growth attached to parent (yeast, mold, sponges)
•Sporulation - formation of spores (fungi, algae)
•Regeneration - replace damaged tissues (starfish, planaria)
•Benefits - highly efficient; large # of offspring in short period of time
•Pitfalls - eliminates/limits genetic variation; reduces chances for a population to
adapt to environmnetal stress
Sexual
•Fertilization - joining of 2 haploid cells (sex cells - gametes)
•Pollination in plants
•Gametes have 1/2 the amount of hereditary material - combines to form a new
organism
•Meiosis - production of gametes - only occurs in specialized sex organs
•Makes up "genes" - parts of DNA strand that code for a specific protein
•phenotypes - physical traits (color, size, types of appendages, etc)
•genotypes - genetic make-up coding traits(homozygous, heterozygous)
Mendel & Heredity
Heredity – the passing of traits from parent to offspring
- genes are made up of DNA
- located on chromosomes
Alleles – different forms of genes
- meiosis separates chromosome pairs
- gives each sex cell 1 allele for each trait
Genetics – the study of how traits are inherited through the actions of alleles
- Gregor Mendel – father of genetics
 Austrian monk (1822)
 Experimented with garden peas
 Thought is was possible to predict outcome of flowers
 “Experiments with Plant Hybrids”
 Worked with large numbers to create more accurate predictions (30,000 pea plants over 8
years)
- Purebreds – an organism that always produces the same traits generation to
generation
- Cross-pollination – taking pollen off male and placing it on female reproductive
organ of different plant
• Dominant traits
 A factor that dominates or covers up the other traits
 The trait expressed/shown
• Recessive traits
 The trait that disappears (doesn’t show)
 Can show if recessive traits combine from both parents
- Punnett square
 Dominant and recessive alleles are represented by letters
 Capital letters represent dominant traits

Lowercase letters represent recessive traits
Phenotype
Genotype
physical expression of
a specific genotype
genetic make-up that
codes a specific gene
color, shape, physical
attribute expressed
Dominant &
Recessive Traits
Homozygous
- 2 alleles exactly the
same
- ex. BB or bb
Heterozygous
- 1 dominant & 1
recessive allele
- ex. Bb
Incomplete dominance
- the production of a phenotype that is intermediate to those of the two homozygous parents
- ex. Crossing red homozygous flowers with white homozygous flowers and the offspring
expressing
- ex. pink flowers
- one allele is not able to be dominant over the other
Multiple alleles
- a trait controlled by more than two alleles
- ex. Blood type in humans
 A, B, O
 A & B are both dominant
 O is recessive
 Possible phenotypes:
o A – could have AA or AO
o B – could have BB or BO
o AB – only AB
o O – only OO
Polygenic inheritance
- when a group of gene pairs acts together to produce a single trait
 eye color
 fingerprints
 height
 weight
 body build
 shapes of features
 skin color
- not limited to humans, plants have traits controlled by polygenic inheritance
- genes may influence a small amount but creates the variety that is expressed
 many different skin tones in ethnic grouping
 many different shades of blue eyes
 many different shades of brown hair