Download Midterm Review - Jupiter Files

Living Environment Review
High School Science Department
Mr. Noto
The Scientific method
Upco’s Unit 1 (Ch 1-2) p1-16
The Scientific method – a series of steps that scientists used to test a
hypothesis.
Hypothesis-a proposed explanation (prediction) about a possible explanation
to a problem
Steps to the scientific method:
ProblemHypothesis Experiment (Safety precaution & materials)
Observation (data) Conclusion Repeat Experiment
Variable- the part of the experiment being tested
Independent Variable- variable that changes or is manipulated during the
experiment (time, temp, Ph, light intensity)
Dependent variable- variable that is measured as a result or effect of the
independent variable
Controlled Experiment- used to test your hypothesis
Control- does not contain the variable
In a controlled experiment you have only one variable and a control.
When conducting a controlled experiment you must have 2 groups:
Experimental group- the group that receives the variable
Control group- the group does not receive the variable (water, placebo,
sugar pills).
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Scientific Graph- shows a relationship between the independent variable
and dependent variable.
A scientific graph must consist of the following components:
Scaling- are you numbering in 2’s, 10’s, 100’s, 1000’s or 1’s
Always label your x and y axis and place unit of measurement (cm, m, in,
°C, mg/dl)
X axis always label with the Independent variable.
Y axis always label with the Dependent variable.
Give your graph a Title: The effect of _______ on _________.
y
ax
is
x axis
Conclusion- answer to your problem based upon data collected during the
experiment
Experiments should always include large sample size and must be repeated
for accuracy.
The 8 life functions
Upco’s Unit 2-Ch. 3(p17-22)
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1. Transport- is the life process that includes the absorption and
circulation of materials throughout an organism.
2 Types: Passive transport & Active Transport
2. Respiration- the process by which energy is released from food.
3. Regulation- the life activity responsible for the control and
coordination of all the various activities of an organism.
4. Excretion- the removal of harmful cellular wastes.
5. Growth- is an increase in size and/or number of cells of an organism.
6.
Reproduction- the production of new individuals.
7. Synthesis- all chemical reactions in which large molecules are
produced from smaller molecules.
8. Nutrition- obtaining materials (food) from the environment and
processing them for their own use.
2 Types: Autotrophic Nutrition and Heterotrophic Nutrition
Metabolism-the sum total of all life activities taking place in
an organism.
Homeostasis- the maintenance of a stable internal environment
in spite of changes in the external environment
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Parts of Animal & Plant Cells
Upco’s Unit 2-Ch 4 (p 22-33)
All living things are made up of one or more cells.
Cells are the basic unit of structure and function of all living
organisms.
Organelles- “mini organs”
tiny structures that carry out life functions inside of cells
Both animal and plant cell contain the following organelles:
1. Plasma/Cell membrane- a double-layered structure that surrounds the
cell. Protects what materials go in and out of the cell.
2. Cytoplasm- the watery cell fluid that contains the cell organelles.
3. Nucleus- controls all cell activities in the cell. Contains hereditary
information-Chromosomes.
4. Nucleolus- located inside the nucleus and makes ribosomes.
5. Ribosomes- where proteins are synthesized
6. Endoplasmic Reticulum- transport materials throughout the cell.
7. Mitochondria- organelles involved in Cellular Respiration and
provides energy (ATP).
8. Golgi Complex- a stack of membrane bounded channel. They
synthesize, package, and secrete cell products.
9. Lysosomes- membrane –bound sacs contain digestive enzymes
10. Vacoules- Sac- like structures used by the cell to store various
materials including water, wastes, and food.
Animal cell only have CENTRIOLES- involved in cell division located
in pair, near the nucleus. Animal cells have a (round) circular shape.
Plant cell only have CHLOROPLASTS & CELL WALL!!!!
Chloroplasts- contain chlorophyll and the site of photosynthesis.
Cell wall- the outer layer of a plant cell, gives plant cells their square
shape.
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Transport (Upco’s Ch 4-p24)
Movement of materials (CO2, O2, C6H12O6, H2O) in and out of the cell
Plasma/Cell Membrane- made up of a (2) bi-layer lipids and proteins.
- maintain HOMEOSTASIS
- Semi-permeable (allows certain material in & out of the cell according
to size. Small particles can pass through
- Plasma/cell membrane has cell receptor molecules on the outer
membrane.
-Receptor molecules play an important role in the interactions between
cells by binding to hormones and other molecules sent as communication
signals from cells such as nerve cells.
Passive Transport
No Energy (ATP) required.
H L concentration
Ex. Osmosis – movement of water
only.
Ex. Diffusion- movement of
dissolved particles (glucose, carbon
dioxide & oxygen).
Active Transport
Energy (ATP) required.
L H concentration
Ex. Phagocytosis- WBC engulf
(surround) a pathogen.
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BIOCHEMISTRY (Upco’s p135)
Organic Molecule
Combination of carbon (C) &
Hydrogen (H).
Ex. Carbohydrates (sugars), Lipids
(fats), Proteins, Nucleic Acids
Inorganic Molecule
Lack the combination of Carbon (C)
& Hydrogen (H).
Ex. Salts, H2O, CO2, Inorganic acids
& Bases.
Enzymes (Upco’s p 137-139)
Enzymes – always end in “ase” Ex. Lipase, Protease.
Increase or decrease the rate of reactions (digestions, photosynthesis,
cellular respiration)
Catalyst- assists the reaction, but remains unchanged (re-useable).
Active Site- formation(shape) of pocket where enzyme & substrate
connect together.
Substrate- is the substances that the enzyme works on.
When an enzyme and substrate combined they form an EnzymeSubstrate Complex.
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Factors that affect enzyme rate
1. pH*- measures whether a solution is an acid or base (Upco’s p138)
Acids- pH 1-6 1-strong
Neutral- PH 7 (water)
Bases- pH 8-14 8- weak
6-weak
14-strong
2. Temperature- as temp increase, rate of reaction will increase
3. Shape
4. Amount of substrate or enzyme concentration
Autotrophic Nutrition and Heterotrophic Nutrition
Autotrophic Nutrition
Organism that can synthesize (make)
organic (glucose) food substances
from inorganic substances.
Plants & Algae- Autotrophs
Heterotrophic Nutrition
Organism that must obtain nutrients
from the environment.
Mammals (Humans), ReptileHeterotrophs
By the process called photosynthesis Digestion
Photosynthesis (Upco’s Ch 17 p143-145)
-Requires sunlight
- take place in the chloroplast. Chloroplast contains chlorophyll.
- It converts light energy into chemical energy.
Formula:
CO2+ H2O -------light energy, enzymes, chlorophyll---------------->O2+ C6H12O6+ H2O
Carbon Dioxide + water -------light energy, enzymes, chlorophyll---------------->oxygen+ glucose +water
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Factors that affect Photosynthesis
1.
2.
3.
4.
Amount of CO2 + H2O
Light Intensity
Temperature
Minerals
Parts of the Leaf
1. Cuticle (waxy layer) - protection
2. Palisade – Photosynthesis layer
3. Spongy- Photosynthesis layer
4. Stomates- gas + water exchange
5. Guard cells- open and closed the stomates
6. Xylem + Phloem – (veins) transport materials throughout the leaf
7. Upper Epidermis - protection
8. Lower Epidermis- the place where stomates are found.
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Cellular Respiration (Upco’s p145-147)



Takes place in both animal & plant cells
Food molecule (starch/glucose) is processed into a useable form
(ATP) for the body.
Take place Mitochondria
Formula:
O2+ C6H12O6 ------- enzymes ----------------> CO2+ H2O+ ATP
ATP-ADP Cycle
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Energy for all
cell activities
-P
(remove a P)
ATP
Energy from
glucose
ADP
+P
(add a P)
ADP + P= ATP stored energy
ATP- P= ADP energy release for all cell activities
*Remember when you make a bond you store energy and when you
break a bond you release energy.
Human Digestive System (Upco’s Ch. 6 p39-42)
*Responsible for taking in and processing (breakdown) food (nutrients)
to provide body with the energy needed for metabolism
-Digestive system includes the mouth, esophagus, stomach, liver,
pancreas, small intestines, large intestines, rectum and anus
-
nutrients must be broken down using enzymes-large molecules into small
molecules to diffuse through cell membrane
Large Complex Molecules
Carbohydrates, starches
Lipids (fats)
Proteins
Simple End Products
Glucose (simple sugars)
Fatty acids and glycerol
Amino acids
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-Digestive system disorders include: ulcers, tooth decay, appendicitis,
diarrhea and constipation
Human Circulatory System (Upco’s Ch 6 p42-45)
*Responsible for transporting and circulating materials throughout the
body including digested nutrients, oxygen, carbon dioxide and other
wastes
-Circulatory system includes the heart, arteries, veins, capillaries and
blood
-Blood is made up of plasma, red blood cells (RBC), white blood cells
(WBC), and platelets
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Blood Component
Plasma
Red Blood Cells
White Blood Cells
Platelets
Function
Liquid medium
Transport oxygen
Fight infections, produce antibodies
Blood clotting
-Circulatory system disorders include: high blood pressure, heart attack,
leukemia, and anemia
Human Respiratory System(Upco’s Ch 7 p49-52)
*Responsible for exchanging oxygen and carbon dioxide between the
body and the external environment
-Respiratory systems includes nasal passage, pharynx, larynx, epiglottis,
trachea, diaphragm and lungs
-Gas exchange takes place in the alveoli (air sacs) in the lungs-oxygen
diffuses into blood and carbon dioxide diffuses out of blood p 51
12
-Diaphragm used in breathing
inhalation- breathing in
exhalation- breathing out
-Disorders of the respiratory system include bronchitis, asthma,
emphysema, lung cancer and pneumonia
Human Excretory System (Upco’s Ch 7 p52-54)
*Responsible for getting rid of metabolic waste from the body
-Excretory system includes the skin, lungs, urinary system, and liver
Metabolic waste
Carbon dioxide
Water
Formed by
Cellular respiration
Cellular respiration, other cell
activities
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Urea
Mineral salts
Protein digestion
Breakdown of cell compounds
-Disorders of the excretory system include: kidney stones, gout, and
uremia. And cirrhosis of the liver
HOMEOSTASIS
(Upco’s Unit 5- Ch 16-17 p101-130)
Homeostasis- the maintenance of a stable internal environment
(dynamic equilibrium)
Feedback Mechanisms- used to help an organism maintain balance. (p
150)
Examples:
Insulin and blood glucose level
Stomates and guard cells
Sensor detects high blood
sugar level.
Lower blood
sugar, insulin
production
stops.
Pancreas
secretes
insulin.
Blood sugar level
drops.
Disease- A failure to maintain homeostasis; any change other than an
injury that disrupts the normal function of the body
- can result from organ malfunction, toxic substances, poor nutrition,
inherited disorders or risky personal behavior
- can result from cancer (uncontrolled cell division)
- can result from the invasion of a pathogen (microbes)
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Types of pathogens: virus, bacteria, fungi, parasites
Immune System
(Upco’s p147-149)
Protects the body against pathogens (invaders) by recognizing antigens
(foreign proteins) on the surface of a bacteria or virus
The Immune system includes the following organs:
-tonsils, lymph nodes, lymph vessels and fluid, bone, marrow, thymus
gland, spleen, blood (white blood cells-WBC)
White blood cells (WBC) produce antibodies (proteins) that are specialized
for a particular antigen.
White blood cells may engulf (phagocytosis) the invading pathogen.
Types of Immunity
•Active Immunity- occurs when the body makes its own antibodies to
a particular antigen
*stimulates antibody production-Ex: vaccines
•Passive Immunity- is a temporary immunity to a disease produced by
passing antibodies into the body
*Ex: breast feeding
How are vaccines made?
Vaccine- an injection of a weakened or dead pathogen
Steps to a vaccination;
1. Obtain a pathogen and weaken or kill it
2. Introduce the weakened pathogen into the body (orally or by
injection)
3. WBC recognize the invader (antigens) as if it were alive
4. WBC produce specific antibodies
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5. Antibodies remain and WBC “remembers” the specific pathogen
*If the same pathogen is ever reintroduced into the body the
antibodies will respond quickly to destroy it. (Active Immunity)
AIDS (Auto Immune Deficiency Syndrome)
•AIDS is caused by HIV (Human Immunodeficiency Virus)
• HIV destroys T-cells (WBC)
•Immune system weakens-can’t fight off other pathogens
•AIDS patients usually die from other diseases they can not fight off
•currently there is no cure or vaccination for this disease
REGULATION
(Upco’s Ch8-p58-62)
Regulation- the life process by which cells and organisms respond to change
Regulation in humans involves the Nervous system and the Endocrine
system.
Human Nervous System
-Includes the brain, spinal cord, and nerve cells (neurons)
-Responds to stimuli (changes in the environment)
-Nervous system provides FAST Response
-Damage to the nervous system is permanent
Structure of a Neuron:
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*neurons communicate by electrical impulses and neurotransmitters
(chemical messages)
*Dendrites detect a stimulus
*Synapses- spaces between adjacent neurons
*Neurotransmitters are used for communication between neurons
*Receptor molecules on dendrites receive message
-Nervous system disorders include: Cerebral Palsy, Meningitis, Polio, and
Paralysis
Human Endocrine System
-Includes all the glands of the body
-Glands produce hormones (chemical messages) that get transported in
the blood
-Endocrine system provides a SLOWER response to changes inside the
body
Gland
Hormone produced
Thyroid
Thyroxin
Pituitary
Growth hormone
Pancreas
Insulin
Testes
Testosterone
Ovaries
Estrogen, Progesterone, LH, FSH
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Reproduction and Development
(Upco’s Unit 3 Ch 9-12 p69-100)
•Reproduction is the process by which living things produce
other living things of the same species.
•Only members of the same species can reproduce sexually.
There are two types of reproduction, asexual and sexual.
Asexual reproduction requires only one parent and the offspring
are identical.
*Examples of organisms that reproduce asexually:
bacteria, amoeba, paramecium
Sexual reproduction requires two parents and the off the
offspring is genetically different from the parents. Each parent
contributes half the genetic information in sex cells or gametes.
*Examples of organisms that reproduce sexually:
humans, plants, fish, insects
If species stop reproducing they risk extinction.
Types of Cell Division
MITOSIS
*All cells in the body (except sex cells) are produced my
mitosis (mitotic cell division)
*mitosis is used for asexual reproduction
*Formation of two new daughter cells that are identical
(same number of chromosomes). Ex. Parent has 46
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chromosomes and each daughter cell has 46
chromosomes.
*Example of different types of Asexual Reproduction are :
Budding, Binary Fission, Sporulation Regeneration, And
Vegetative Propagation.
*The differences between plant and animal Mitosis:
Animal cell have centrioles, animal cells cytoplasm divides
by “pinching in” and plant cell, form a cell plate is made to
divide cytoplasm.
-
Asexual reproduction preserves hereditary characteristics- NO
VARIATION.
The 5 stages of Mitosis are:
I (Interphase) – Introduce- Chromosomes introduce themselves to process
of copying (replication or duplication).
P(Prophase)- Produces- (form) spindle fibers and nuclear membrane
disappears.
M (Metaphase)-Middle- Chromosomes move to the middle of the cell.
A (Anaphase)-Apart- Chromosomes move apart from each other or cells
begins to separate.
T (Telophase)-Two- Two new daughter cells are produced and the nuclear
membrane reappears around each cell. Each daughter cell is identical as the
parent cell.
Cancer- is a group of diseases characterized by uncontrolled cell
division of abnormal cells.
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MEIOSIS
*Meiosis (meiotic cell division) is involved in the production
of sex cells (gametes)
*Meiosis reduces the number of chromosomes by half
2N (diploid)  1N (monoploid/haploid)
Results: 4 monoploid cells with different genetic
information. VARIATION!!!
COMPARISON OF MITOSIS AND MEIOSIS
MITOSIS
asexual reproduction
2 new identical daughter cells
MEIOSIS
sexual reproduction
4 new daughter cells (gametes)
that are different
daughter cells=1N
Variation
parent cell=2N
daughter cells=2N
no variation
parent cell = 2N
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Human Reproduction and Development
(Upco’s Ch 11 p81-83, Ch 12 p90-94)
Male Reproductive System
•Two major functions of male reproductive system:
1. Produce sperm
2. Deposit sperm inside female
Part of system
Testes
Scrotum
Glands
Urethra
Penis
Function
Produce sperm and testosterone
Keeps testes 2°C cooler than body
Produce liquid and nutrients for sperm
Tube for urine and semen to leave body
Deposits sperm inside female
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Female Reproductive System
•Two major functions of female reproductive system:
1. Produce egg (ova)
2. Site for fertilization and embryonic development
•Female menstrual cycle and pregnancy is controlled by hormones
Part of system
Ovary
Oviduct (fallopian tube)
Uterus (womb)
Vagina (birth canal)
Function
Produce eggs and hormones
Site of fertilization
Site of embryonic development
Site of sperm deposition and birth
Fertilization- the union (joining) of egg and sperm nuclei to form a zygote
(fertilized egg)
Two Types of Fertilization:
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External fertilization- takes place inside an aquatic (water)
environment outside the body of the female.
Internal fertilization- takes place inside the body of the female where
the male deposits sperm inside the reproductive tract of the female.
*Fertilization takes place in the females fallopian tube or oviduct.
*Following fertilization the zygote must undergo
embryonic development.
*Zygote undergoes cleavage (mitotic cell division)
*Developing organism is called an embryo
*Blastocyst (hollow ball of cells) implants into the
uterus
*All cells are identical at this point and must go
through differentiation
*Differentiation- cells of the embryo become the
different cells, tissues and organs of the body
*Stem cells- embryonic cells before differentiation
*During differentiation cells use only portions of the
DNA- certain genes turned on and others are turned
off
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*After implantation the placenta and umbilical cord form.
*The placenta and umbilical cord supply the fetus with nutrients and
oxygen from the mother and get rid of waste produced by the fetus.
*All substances that enter the mother’s body will enter the fetus through
the placenta and umbilical cord including tobacco, alcohol and drugs.

To ensure good prenatal care the mother must eat a healthy diet,
proper medical attention and avoid harmful activities.
 Harmful substances can cause birth defects and interfere with fetal
development
 Tobacco causes Low Birth Rate Syndrome
 Alcohol causes Fetal Alcohol Syndrome
Genetics
(Upco’s Unit Four: Ch 13 p101-112, Ch 14 p 112-120, & Ch 15 p 121-130)
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*All living organisms possess a set of instructions (template) called genes.
*Genes determine characteristics or traits.
*Heredity is the passage of hereditary information (genes) from parent to
offspring.

Before passing genes on to the next generation the instructions must
be replicated (copied).
 Replication ensures that the correct hereditary information is passed
on to the offspring, while ensuring that the parent’s information
remains intact.

Genes are found on Chromosomes

Each species has its own unique number of chromosomes and genes

Traits are inherited from parents during reproduction.

The environment can influence the expression of traits.
Ex: Light and chlorophyll production in plants
Offspring may resemble parent even though it is genetically different from
the parent.
Variations are differences in traits. Variations are caused by genetic
recombination in sexual reproduction and mutations.
Mutation-change in the genes or chromosomes of an organism
Gene mutation- change in the genetic code
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Ex: addition: ATTCGTCCGGATTCCGTCCGG
deletion: ATTCGTCCGGATTGTCCGG
inversion: ATTCGTCCGGATTTGCCCGG
*Sickle Cell Anemia is caused by a gene mutation
Chromosome mutation- change in chromosome number or
structure
Ex: Down’s syndrome-extra #21 chromosome
Crossing -over between homologous chromosomes causes
more variations.
THE DNA MOLECULE
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DNA is an inherited set of instructions (template) that are passed
down from parent to offspring (molecular basis of heredity)
DNA contains the coded instruction to make proteins.
DNA stands for deoxyribonucleic acid.
DNA can be found in the nucleus of all living cells.
DNA is made up of subunits called nucleotides.
A nucleotide contains a phosphate, sugar (deoxyribose) and one of
four nitrogen bases. (A, T, G. or C)
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Chromosomes are made up of long chains of nucleotides paired up.
THE DOUBLE HELIX
James Watson and Francis Crick discovered the structure of DNA
in the 1950’s.
DNA structure is
ALPHABET
helix which
letters
words
twisted ladder.
DNA CODE
nucleotides
codon(3 nucleotides)
genes
chromosomes
nucleus
sentences
chapters
book
a double
looks like a
The sides of the ladder are made up of the sugar phosphate backbone held together by
strong bonds.
The rungs (steps) of the ladder are pairs of nitrogen bases held together by weak
hydrogen bonds.
BASE PAIR RULE for nitrogen bases
A  T
C  G
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DNA REPLICATION
During cell division DNA makes exact copies of itself.
DNA strands “unzip” (separate) along the weak Hydrogen bonds
holding base pairs together.
Each Single Strand acts as a template, pairing up with new
matching nucleotides according to the base pair rule.
GENETIC CODE
The genetic code is a message to the cell to make proteins.
COMPARISON OF DNA CODE TO ALPHABET CODE
RNARiboNucleic Acid
Helps DNA synthesize proteins
Three types of RNA
1. mRNA-messenger
2. tRNA-transfer
3. rRNA-ribosomal
RNA made up of nucleotides
DNA
Comparison of DNA and RNA
RNA
Contains the sugar deoxyribose
Contains the nitrogen bases
A,T,C,G,
Double-stranded
Only one kind
Contains the sugar ribose
Contains the nitrogen bases
A,U, C,G
Single-stranded
Three kinds: mRNA, tRNA, & rRNA
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PROTEIN SYNTHESIS
Proteins are made in the cell at the ribosome.
Proteins are made up of different combinations of 20 different
amino acids.
Their structure or shape is determined by the order the amino acids
are put together.
The genetic code determines the order of amino acids and the
structure of the protein.
Protein Synthesis
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EVOLUTION
Unit 6 – Upco’s Ch 18 (p155-164), Ch 19 (p 165-176), Ch 20 (p 177-188)
Evolution-the gradual change of species over a long period of time
Biological or organic evolution refers to the changes in living
organisms.
EVIDENCE OF EVOLUTION:
1. Fossil evidence
2. Comparative AnatomyHomologous structures
3. Comparative Embryology
4. Comparative Biochemistry DNA , enzymes, proteins
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Evolutionary Theory (p166)
1. Spontaneous Generation
2. Use Disuse Lamarck- inheritance of acquired traits
(*note organisms cannot want or need to change and
traits can not be acquired)
3. Natural Selection Darwin
*Overproduction
*Competition
*Variation
*Survival of the Fittest
*Inheritance of Variations
*Evolution of new species
4. Modern Theory of Natural Selection includes
knowledge of DNA
 Genes of inherited variations lead to adaptations that give
organisms a better chance of survival
 Favorable genes increase in number in a population because
those organisms survive better and live to reproduce and pass
the traits on
 Genes with low survival value decrease from generation to
generation and eventually disappear
 If the environment changes less adaptive traits may now
become favorable and increase in number
*REMEMBER VARIATIONS COME FROM GENETIC
RECOMBINATION AS A RESULT OF SEXUAL
REPRODUCTION AND FROM MUTATION.
Examples of Evolution in Modern Times (p 177-178)
1. Pesticide Resistance
2. Antibiotic Resistance in bacteria
3. Peppered Moths
4. Adaptive Radiation –Darwin’s Finches (p 179)
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*Geographic and Reproductive Isolation may lead to new species.
Time Frame for Evolution
1. Gradualism-
2. Punctuated Equilibrium
Factors that affect Human evolution
1. Medical Knowledge
2. Modern Transportation
3. Advanced Technology
4. Genetic Engineering
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ECOLOGY
Unit 7 Upco’s Ch21 (p189-198), Ch 22 (p199-204), Ch 23 (p211-220), Ch 24(p221-236)
Ecology study of living organisms interacting with their
environment and other organisms
Levels of organization
SpeciesPopulationsCommunitiesEcosystemsBiosphere
1.
2.
3.
Requirements for a Stable Ecosystem
Constant supply of energysun
Organisms to convert energy into usable
form(glucose)photosynthesis
Recycling of materialsdecomposers
Biotic factors-living organisms
∙Producers-organism that manufacture food
∙Consumers-organisms that eat other organisms
∙Decomposers-organisms that breakdown dead organisms
Abiotic factors- non-living parts of the environment
EX: soil, water, air, light, temperature, minerals
Factors that affect an aquatic ecosystem
1. Amounts of oxygen and carbon dioxide
2. Temperature and light
3. Amounts of dissolved minerals
Energy Flow in an Ecosystem
All organisms in an ecosystem are either autotrophs (producers) or
heterotrophs (consumers and decomposers).
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Common Food Relationships
1. Saprophytes-decomposers Ex: bacteria or fungi
2. Herbivores-animals that eat plants or plant parts Ex: cow, insects
3. Carnivores- animals that eat other animals Ex: lion, wolf
Predator-hunts and kills prey (food)
Scavengers-feed off dead leftovers Ex: vulture, seagull
4. Omnivores- animals that feed on both plants and animals
Symbiotic Relationships
1. Mutualism-both organisms benefit + , +
2. Commensalism –one organism benefits, one is unaffected +, 0
3. Parasitism – one organism benefits, one is harmed +, -
Food Chain- shows flow of energy
Grasscow human
ProducerPrimary consumerSecondary consumer
(herbivore)
(carnivore)
*decomposers found at each level
At each level of the
*arrows point toward organism that does the eatingarrow shows
pyramid the amount
energy flow
of available
*less energy gets transferred at each level of the
food chain energy
as does
*organisms use most energy to carry out theirdecreases
own metabolism
to the
population size of the
maintain homeostasis
organism.
All food chains in an ecosystem interconnect to form a food web.
Each organism in a food web is interconnected to others.
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FOOD WEB
37
Recycled Materials
1. The Carbon-Oxygen Cycle
2.
The Water Cycle
3.
The Nitrogen Cycle
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Biodiversity-the sum total of all the different species
BIODIVERSITY=STABILITY
Habitat-the place where an organism lives
Niche –the role an organism plays in the ecosystem (what and
where it eats)
*Only one type of organism can fill each niche-otherwise
competition occurs
Carrying Capacity –the number of organism any habitat can
support.
*limited by the amount of available energy (food), water,
oxygen, carbon dioxide, minerals, temperature and recycled
materials
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Ecological Succession
*Change in an ecosystem over time where a simple ecosystem is
replaced by more complex ecosystem
Forest Succession
Pond Succession
*Pioneer
Organisms-the first organisms that populate a given
community EX: lichens, mosses, weeds
*Climax Community-an ecosystem that remains stable over a
long period of time.
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Human Impact on the Ecosystem
Humans are the only species that can impact the environment in a
negative way, but they are also capable of improving or having a
positive impact as well.
Human Survival Requirements
1. Clean Air and Water
2. Nutritious Food
3. Fertile Soil
4. Space for Shelter and Living
Human Population Growth-rapidly growing could exceed carrying
capacity
Human Impact Includes:
1. Pollution
a. Water (thermal-factories)
b. Air (burning fossil fuels and factories)
c. Soil (using chemical biocides and fertilizers)
2. Endangered Species-caused by over hunting and destroying
habitatsleads to extinction and decrease in biodiversity
3. Deforestation-habitat destruction
4. Biocide useincludes pesticides, insecticides, herbicides
5. Waste disposal
a. Solid (garbage)
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Chemical
c. Nuclear
Global Warmingcaused by increased CO2 due to cutting
down trees and pollution from burning fossils fuels(gas, oil,
coal)
Ozone Destructionozone gas ( O3) protects the earth from
UV rays from the sun and chemicals in the atmosphere from
humans caused a whole in the ozone layer
Acid Rain caused by pollution in air from factories and
forms of transportationchanges pH of soil and water
b.
6.
7.
8.
Positive Impact by Humans on their Environment
*Human can also fix and improve their environments
1.
2.
3.
4.
Environmental Lawshelp to regulate the damage or
negative impact humans cause
a. Freshwater Wetlands Act
b. Hazardous Waste Disposal Regulations
c. Air Pollution Control Laws
d. State Environmental Quality Review (SEQR) Act
e. Returnable Container Law and Recycling Laws
f. Endangered Species Act
Conservation of Natural Resources- Fossil Fuels and other
non-renewable resources (mineral and metals)
Wildlife Preservation helps maintain biodiversity
Biological Pest Control use alternative methods other than
chemicals which get into the ecosystem
Ex: *Use of sex hormones to attract and trap pests
*Natural Predators-eat pest
*Breeding pest resistant plantsgenetic engineering
*Releasing Sterilized Male Insectscan’t reproduce
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