Final Exam Review
ACCELERATED BIOLOGY
SECOND SEMESTER
Unit 9 – DIGESTION and EXCRETION
 Label the diagram below and provide functions for each part.
oral cavity
esophagus
liver
gall bladder
large intestine
appendix
anus
stomach
pancreas
small intestine
rectum
Unit 9 – DIGESTION and EXCRETION
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Oral cavity – mechanical digestion and chemical breakdown of
starch (amylase)
Esophagus – peristalsis moves food to stomach
Liver – produces bile, converts glucose  glycogen
Gall bladder – stores bile
Stomach – mechanical breakdown of all food, chemical
breakdown of proteins (pepsin)
Pancreas – secretes enzymes amylase, protease, and lipase
Small Intestine – absorption of all nutrients
Large Intestine – water absorption
Appendix – no known function! (vestigial structure)
Rectum – solid waste is stored
Anus – solid waste is eliminated
Unit 9 – DIGESTION and EXCRETION
 Explain the difference between chemical and mechanical
digestion. Name two places where each occurs.

Mechanical – food is broken into smaller pieces
 Occurs in the mouth (chewing) and stomach (churning)
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Chemical – Macromolecules are broken down into their
building blocks by enzymes
(carbohydrates  simple sugars)
 Proteins are broken down in the stomach
 ALL biomolecules are chemically broken down in the SI
Unit 9 – DIGESTION and EXCRETION
 Why is the pH of the stomach acidic?

Pepsin, the enzyme that breaks proteins into amino acids,
works best at a low pH.
Unit 9 – DIGESTION and EXCRETION
Organ
Type of
Digestion
What
Macromolecule
is digested?
What enzymes
are used?
Mouth
mechanical and
chemical
starch
amylase
Stomach
mechanical and
chemical
proteins
pepsin
all
sucrase (sucrose)
maltase (maltose)
lactase (lactose)
amylase (starch)
protease (proteins)
lipase (lipids)
Nuclease (nucleic
acids)
Small Intestine
chemical
Unit 9 – DIGESTION and EXCRETION
 List/describe three specific functions carried out by the large
intestine
1. absorbs minerals & water
2. a colony of bacteria live in the colon and help the body synthesize
many compounds you cant get from food
 Vitamin K
 Several B vitamins
3. the rectum (last part of the colon) stores solid waste until you
find a socially acceptable time and place! 
Unit 9 – DIGESTION and EXCRETION
Describe the role of each of the following in digestion.
 hydrochloric acid – lowers pH of stomach so Pepsin can
chemically break down proteins
 bile – emulsifies lipids (breaks them into smaller pieces,
increases surface area)
 sodium bicarbonate – raises pH in the duodenum so enzymes
there can work
 mucus – moistens food so it is easier to mechanically breakdown
and swallow
Unit 9 – DIGESTION and EXCRETION
 In the chart, list all the enzymes that digest each macromolecule.
Macromolecule
All enzymes that digest them
Carbohydrates
Complex Carbs
amylase  starch (mouth)
Simple Sugars
Sucrase  sucrose (small intestine)
Maltase  maltose (small intestine)
Lactase  lactose (small intestine)
Proteins
Pepsin (stomach), protease (small intestine)
Lipids
Lipase (small intestine)
Nucleic Acids
Nuclease (small intestine)
Unit 9 – DIGESTION and EXCRETION
 Explain where chemical digestion occurs for each of the
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nutrients.
Carbohydrates –
 mouth (amylase  starch)
 small intestine (sucrase, maltase, lactase  simple sugars)
Proteins –
 stomach (pepsin)
 small intestine (protease)
Lipids –
 small intestine (lipase)
Nucleic acids –
 small intestine (nuclease)
Unit 9 – DIGESTION and EXCRETION
 Where does chemical absorption and water absorption take
place?
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chemical absorption – small intestine
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water absorption – large intestine
Unit 9 – DIGESTION and EXCRETION
 What is the function of the villi?
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Increases the surface area so more absorption can take place
Unit 9 – DIGESTION and EXCRETION
 How is the health of an individual with anorexia or bulimia
affected?
 Anorexics – starve themselves and/or over exercise
 may never mature sexually or stop menstruating
 body temperature and pulse are low
 hair thin and dry
 resistance to infection drops
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Bulimics – binge and then purge (vomiting or using laxatives)
 purging remove salts  muscle weakness, kidney disease
 vomiting destroys tooth enamel
Unit 9 – DIGESTION and EXCRETION
 What is excretion?
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Process that rids the body of toxic chemicals, excess water,
salts, carbon dioxide, and maintains osmotic (water) and pH
balance
Unit 9 – DIGESTION and EXCRETION
 Label the diagram of the urinary system with the following:
kidney, urinary bladder, ureter, urethra. Also, give the
function(s) of each part.
kidney
ureter
urinary bladder
urethra
Unit 9 – DIGESTION and EXCRETION
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kidney – excretes nitrogen
wastes, salts, water, and
other substances in urine
 composed of ~ 1 million
microscopic units called a
nephron
urinary bladder – stores
urine (expands)
ureter – tube that takes
urine from the kidney to the
urinary bladder to be stored
urethra – Urine is emptied
through the urethra
Unit 9 – DIGESTION and EXCRETION
 What is a nephron?
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functional unit of the kidney
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each kidney contains
~1,000,000 nephrons!
(yes, they are microscopic)
Unit 9 – DIGESTION and EXCRETION
 What is the job of a nephron?
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This is where filtration,
reabsorption, and secretion
take place!
Unit 9 – DIGESTION and EXCRETION
 List the 3 different phases that occur as blood flows through a
nephron and explain what happens during each phase
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filtration – blood pressure inside the capillaries forces fluid
containing water, salt, glucose, amino acids, and urea into the
hollow interior of Bowman’s capsule. This fluid is called
filtrate.
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reabsorption – as the filtrate passes through the renal tubules
useful molecules; glucose, ions, and some water, is reabsorbed
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secretion – when substances pass from the blood into the
filtrate. This eliminate toxic substances from blood
Unit 9 – DIGESTION and EXCRETION
 List the 3 different phases that occur as blood flows through a
nephron and explain what happens during each phase
Unit 9 – DIGESTION and EXCRETION
 What 3 substances are found in urine?
1.
2.
3.
4.
urea
water
salt
(excess vitamins)
Unit 9 – DIGESTION and EXCRETION
 Write T for True, F for false.
Correct the false statements to
make them true.
 FALSE The renal artery takes clean
blood away from the kidney.
 TRUE The function of the kidney is
to maintain homeostasis by
regulating the amount of sugar,
salt, water, amino acids, and urea
present in the blood.
 TRUE Excretion is necessary
because an organism is constantly
producing waste material.
Unit 11 - PLANT REPRODUCTION AND
DEVELOPMENT
 Describe the evolution of modern plants from green algae.
Include the challenges that plants faced living on land.
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Challenges of life on land include:
1.
obtaining resources from two places at once
• light and CO2 found above ground
• water and minerals found below ground.
2.
staying “afloat” in air
3.
maintaining moisture
4.
reproducing without water
Unit 11 - PLANT REPRODUCTION AND
DEVELOPMENT
 What are the adaptations that allowed plants to survive on land.
1.
2.
3.
4.
vascular system (xylem and phloem)
lignin: chemical that hardens the plants’cell walls
cuticle and stomata
production of gametes in protective cells
 sperm travel within pollen
 embryos are eventually dispersed as seeds, enclosed in
protective coats
Unit 11 - PLANT REPRODUCTION AND
DEVELOPMENT
 Complete the following table with an appropriate YES or NO in
each box.
Bryophytes
Pterophytes
Gymnosperms
Angiosperms
Need water for
fertilization?
Yes
Yes
No
No
Vascular
tissue?
No
Yes
Yes
Yes
Pollen?
No
No (spores)
Yes
Yes
Seeds?
No
No
Yes
Yes
Fruit?
No
No
No
Yes
Unit 11 - PLANT REPRODUCTION AND
DEVELOPMENT
 Conifers produce seeds in CONES and angiosperms produce
seeds in FRUITS.
Unit 11 - PLANT REPRODUCTION AND
DEVELOPMENT
 Label the parts of a flower including: stigma, style, ovary, pistil,
anther, filament, petal, sepal, ovule, egg.
Unit 11 - PLANT REPRODUCTION AND
DEVELOPMENT
 Label the parts of a flower including:
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stigma – top, sticky portion of the pistil that receives the pollen
style – long tube of the pistil that leads to the ovary
ovary – where fertilization occurs (becomes the fruit)
pistil – female reproductive structure (stigma, style, ovary)
anther – produces pollen
filament – supports the anther
petal – bright and colorful to attract pollinators
sepal – protects the flower as a bud
ovule – where fertilization occurs (develops into the seed)
egg – unite with sperm inside ovule to form zygote
Unit 11 - PLANT REPRODUCTION AND
DEVELOPMENT
 Name one advantage and one disadvantage of self–pollination.
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advantage – easier (pollen does not need to be transported far)
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disadvantage – offspring are clones of the parent; no genetic
variation
Unit 11 - PLANT REPRODUCTION AND
DEVELOPMENT
 Name one advantage and one disadvantage of cross–pollination.
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advantage – genetic variation
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disadvantage – pollen needs to be transported from one plant
to another (insects, birds, bats, wind)
Unit 11 - PLANT REPRODUCTION AND
DEVELOPMENT
 How are plants pollinated? fertilized? What happens first?
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Pollination – Pollen is transferred by wind, water, insects,
birds, bats
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Fertilization – When pollen lands on the stigma, a long pollen
tube develops, allowing the sperm to travel down the style to
the ovary, and fertilize an egg inside the ovule!
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Pollination occurs first!
Unit 11 - PLANT REPRODUCTION AND
DEVELOPMENT
 Explain the difference between
pollination and fertilization.
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Pollination – Pollen is
transferred from the anther
(male) to the stigma
(female)
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Fertilization – When egg
and sperm unite. Occurs
inside the ovule.
Unit 11 - PLANT REPRODUCTION AND
DEVELOPMENT
 What is necessary for germination to occur?
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water
proper temperature
Unit 11 - PLANT REPRODUCTION AND
DEVELOPMENT
 What is a tropism?
growth of plant in a certain way in response to a stimulus
 towards stimulus (+)
 away from stimulus (–)
 Name and describe three types of tropisms.
 phototropism – towards or away from light
 shoots grow towards light (+)
 roots grow away from light (–)
 gravitropism – towards or away from gravity
 shoots grow against the force of gravity (–)
 roots grow with the force of gravity (+)
 thigmotropism – response to physical contact
 vines coil around a trellis to grow upward
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Unit 11 - PLANT REPRODUCTION AND
DEVELOPMENT
 What is transpiration and how does it affect photosynthesis?
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Transpiration – The evaporation of water out of a plant. Water
is a reactant in photosynthesis!
Unit 11 - PLANT REPRODUCTION AND
DEVELOPMENT
 What are the functions of the following plant parts:
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roots – absorb water, anchor the plant
stem – supports the leaves
leaves – main site for photosynthesis
xylem – transports water up from roots
phloem – transports sugar
Unit 11 - PLANT REPRODUCTION AND
DEVELOPMENT
 Explain the difference between sexual and asexual reproduction.
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asexual – most plants reproduce asexually
 does not require fertilization
 faster and requires less energy
 results in clones of the parent plant
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sexual – usually requires two parent plants
 generates diversity in offspring
 flowers are the reproductive structures in angiosperms
Unit 11 - PLANT REPRODUCTION AND
DEVELOPMENT
 Explain 3 types of vegetative propagation.
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stolon – above ground runners that bud into new plant
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rhizoids – specialized stems that grow underground
Unit 11 - PLANT REPRODUCTION AND
DEVELOPMENT
 Label and provide the function of each part of the leaf.
cuticle A
upper epidermis B
palisade C
mesophyll
spongy D
mesophyll
lower epidermis E
guard cells AB
AC xylem and pholem
Unit 11 - PLANT REPRODUCTION AND
DEVELOPMENT
 Label and provide the function of each part of the leaf.
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cuticle – waxy coating that prevents water loss
epidermis – thick outer layer for protection
palisade mesophyll – tightly packet layer of cells that contain a
lot of chloroplasts and is the main site for photosynthesis
spongy mesophyll – loosely packed cells that can absorb water
guard cells – regulate the opening and closing of the stoma
vascular tissue – transports water, mineral nutrients, and
organic molecules between the roots and shoots
xylem – water
 phloem – sugar
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Unit 12 – ECOLOGY
 Order the following terms from least to most complex:
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organism  population  community  ecosystem 
biosphere
Unit 12 – ECOLOGY
 Distinguish between biotic and
abiotic factors and give
example of each.
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abiotic – nonliving parts of
the environment
 ex) temperature, light, pH,
minerals, rocks
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biotic – living parts of the
environment
 ex) plants, animals,
bacteria, fungi
Unit 12 – ECOLOGY
 What happens to energy as it is passed along a food chain.
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every time energy is passed from one organism to another 10%
is passed on and 90% is lost to the environment in the form of
heat
Unit 12 – ECOLOGY
 Why are there fewer predators in the woods than producers?
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As you move up the trophic levels, there is less energy available
Unit 12 – ECOLOGY
 Explain why most populations tend to stay constant. Is the
human population different?
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They have reached their carrying capacity. Organisms are in
constant competition for limited resources.
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Yes. The human population is still experiencing exponential
growth. This can not continue forever. At some point, it will
need to level off.
Unit 12 – ECOLOGY
 What is biological amplification (magnification)?
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As toxins (DDT for example) move up the food chain, they
become more concentrated at higher trophic levels
Unit 12 – ECOLOGY
 Distinguish between a food pyramid, web, and chain. Show an
example of each. What happens to the amount of energy and
mass available at each level?
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Food chain – shows a single of energy
Food web – shows ALL of the feeding relationships within the
ecosystem. It is a complex system of many interlocking food
chains.
Food Pyramid – shows the organisms that occupy each tropic
levels
Every time energy is transferred, 10% is passed on and 90% is
lost to the environment in the form of heat. Biomass also
decreases as you move up the trophic levels.
Unit 12 – ECOLOGY
 Distinguish between a food pyramid, web, and chain. Show an
example of each. What happens to the amount of energy and
mass available at each level?
Unit 12 – ECOLOGY
 Define the following terms:
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Producer – plants (autotrophs)
Herbivore – animals that eat only plants
Primary consumer – herbivore
Secondary consumer – the second consumer
Carnivore – animals that eat only meat
Omnivore – animals that eat both plants and meat
Unit 12 – ECOLOGY
 Describe what acid rain is, how it is formed, its impact on bodies
of water, and its impact on living organisms.
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sulfur dioxide (released from smokestacks) combines with
water vapor in the atmosphere to form sulfuric acid
rain and and snow carry the sulfuric acid back to earth in the
form of acid rain
lowers the pH of soil and ponds
 inactivates or destroys organism’s enzymes
Unit 12 – ECOLOGY
 What are the causes of global warming?
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Increased greenhouse gases – CO2, NO2, methane, water vapor
 due to human activity
 burning fossil fuels
 deforestation
• trees take in CO2
 agriculture
• livestock like cows produce methane! (burps and farts!)
Unit 12 – ECOLOGY
 What are the impacts of global warming?
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increased average surface temperatures
melting glaciers and polar ice caps
rise in sea levels (could flood coastal cities
bleaching of coral reefs
change weather patterns
 increase number and severity of floods, droughts, storms
Unit 12 – ECOLOGY
 What are the causes of ozone depletion?
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chlorofluorocarbons (CFC’s)
 used in refridgerators, spray cans, and AC units
Unit 12 – ECOLOGY
 What are the impacts of ozone depletion?
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increased exposure to UV radiation from the sun that can lead
to:
 skin cancer
 eye problem (cataracts)
 weakened immune system