Semester Review for AP Biology Second Semester Exam
Ecology
1. What are the characteristics of an r-strategist?
Matures rapidly, usually reproduces only once, produces lots of offspring, little parental care, short
lifespan
2. What are the characteristics of a K-strategist?
Matures more slowly, reproduces several times, but only has a few offspring at a time, parental care lasts
roughly one year or more, long lifespan
3. What is the difference between exponential and logistic type growth? Draw graphs to illustrate your point.
Unlimited
growth, no
limit on
resources
Growth limited by
resources, slows to a stop
whe h carrying capacity is
reached
4. Briefly define :
a. Batesian mimicry- harmless species mimics a species that is dangerous or tastes bad to predator
b. Mullerian mimicry- 2 harmful species resemble each other, makes a cumulative effect against predators
c. Aposematic coloration- bright colors signal an organism that is highly poisonous
d. Cryptic coloration- coloration makes organism blend in with surroundings, camouflage
5. What does the competitive exclusion principle say? Two species can’t both survive in the same niche
6. Give one example for each of the three types of symbiosis.
Parasitism- one species benefits (parasite) while the other is harmed (host)
Commensalism- one species benefits & the other is neither helped nor harmed
Mutualism- both species benefit from the association
7. Looking at the biomass pyramid below, tell which level has the most calories in it and why.
Primary producers have the
most calories, because they’re
the ones who incorporate
energy from sunlight into
carbohydrates; also 90% of
the calories at each level are
used at that level, only 10 %
are passed on.
8. Use the web shown below to draw three food chains.
plants→ mice→ hawk
plants→ herbivorous→ predaceous → toads→ snakes
insects
insects
plants→ rabbits → foxes
9. Choose one of your food chains and identify the producer, primary consumer, secondary consumer and
tertiary consumer. Producers- plants; primary consumer-herbivorous insects; secondary consumer-predaceous
insects; tertiary consumer- toads; quaternary consumer- snake
10. Briefly define
a. Innate behavior- once called “instinctive” behavior, is in born & usually not changed by the environment
b. Fixed action pattern- set of behaviors that can’t be changed
c. Learning- modifying your behavior based on specific events in a lifetime
d. Imprinting- learning behavior at a specific, limited time in an organism’s life
e. Kinesis- changing the rate of an action in response to a stimulus; sometimes called random movement
f. Taxis- changing direction toward or away from a stimulus
g. Altruism- reaction to danger to preserve other members of your gene pool even if it means sacrificing
yourself
11. What is biological magnification? The increase of a toxic substance in a food chain as you move from a
primary consumer to the top predator
Plants
12. What is a sporophyte? Is it haploid or diploid? What is it used for?
Plants reproduce by alternation of generation, alternating diploid & haploid generations
Sporophytes are diploid & produce haploid spores by meiosis. These grow into haploid adult
gametophytes.
13. What is a gametophyte? Is it haploid or diploid? What is it used for?
Gametophytes are haploid & produce haploid gametes by mitosis. Two gametes fuse to make a diploid
zygote that will grow into a diploid adult sporophyte.
14. What are the characteristics of algae? To what kingdom do algae belong? Algae are in Kingdom Protista
Multi or unicellular, photosynthetic, most are aquatic, cell walls, chloroplasts, Multicellular ones have
holdfast to attach to rocks & a plant-like body with a stem-like stipe & leaf-like blades
15. Give four characteristics of bryophytes- mosses, liverworts & horn worts
Nonvascular & seedless, no root system, acquire water & nutrients by osmosis, haploid gametophyte is
the dominant generation
16. Give 3 characteristics of Tracheophytes.- All vascular plants are tracheophytes
Protective layer around the gametes
Multicellular embryos
Cuticle- waxy layer that covers everything above the roots to prevent water loss
*Vascular system- xylem to transport water & minerals & phloem to transport sugars
17. Give 3 characteristics of Pteridiophytes.- simplest tracheophytes
Ferns & horsetails
Vascular
Seedless- reproduce by spores
Sporophyte is the dominant generation
18. Give four characteristics of Gymnosperms (they may not all be listed in the review materials. Feel free to
use the textbooks on the shelf.)
Conifers, pines, firs, cypress
Needle or scale like leaves
Reproduce using cones to house seeds
Sporophyte is the dominant generation
19. Give four characteristics of Angiosperms.
Flowering plants- fertilization occurs in the flower
Seeds enclosed in a fruit
Fruit develops from the ovary & is used to help spread seeds
Double fertilization produces a embryo and endosperm to feed it as it first germinates
Cotyledons- “seed leaves” first leaves the plant produces
20. What is the purpose of the seed?
Protects the sporophyte embryo & contains endosperm as a food source
Resistant to drying
21. Label the seed shown below.
A. plumules (become leaves)
B. seed coat
C. cotyledon (endosperm & first
leaves)
D. embryo plant
E. radical- develops into root
22. What is the purpose of the following:
a) Endosperm- food source
b) Embryo- baby plant
c) Radical- will turn into root
d) Cotyledons- seed leaves, sometimes store the food of the endosperm
23. Label the parts of the flower shown below:
24. What is the function of each of the following:
a) Carpel
b) Anther
c) Petals
d) Ovary
Omit
25. What is double fertilization? What happens as a result of double fertilization? Is it seen in plants or
animals?
Omit
26. Compare monocots to dicots:
Roots
Monocots
fibrous like grass
Dicots
tap root- one major root like carrot
Vascular tissue in
stem
vascular bundles are scattered
randomly
vascular bundles arranged in a ring
Flowers
flower parts in 3’s
flower parts in 4’s & 5’s
Leaf venation
parallel
netted, main veins are pinnate or palmate
27. What are the functions of the following plant cell types?
a) Parenchyma
b) Schlerenchyma
c) Collenchymas
Omit
d) Meristem
e) Cambium
28. What is xylem? What is its function? What are traechids and vessel elements?
Plant tissue that transports minerals & water up from the roots to the rest of the plant
Traechids- short dead cells with fairly blunt ends that connect to form a tube for the water
Vessel elements- long, dead cells with pointed ends that connect also to form tubes for water
Both have heavy walls that also give support to plants
29. What is phloem? What is its function? What are sieve tube members and companion cells?
Plant tissue that transports sugars from the location where they are formed (source) the place where they
will be used (sink)
Sieve tube members- living cells that have no organelles but that form long tubes for sugar transport
Companion cells- are next to & connect with sieve tube cells to manage all life functions for them
30. What do the following plant hormones do?
a) Gibberellins- stimulates flowering and the development of fruit
b) Abcissic acid- omit
c) Auxins-stimulates stem elongation, development of fruit, & root growth
d) Cytokinins -omit
e) Ethylene- promotes fruit ripening
31. What is water potential? Water potential is due to the net effect of solute potential and pressure potential;
Water will always flow from an area of high water potential to an area or low water potential
32. Define & give function of:
a) plasmodesmata- openings in the cell walls of plants where the membranes connect to allow for the
flow of fluids
b) Casparian strip- waxy layer in and around the endoderm layer of the root that repels water & forces it
to enter the stele (vascular core of the root) via the cells surrounding it
33. Explain, briefly;
a) Transpiration- loss of water through a plant leaf; polar nature of water means that cohesion of water
molecules cause more water to rise from the root to replace the water lost
b) Root pressure- forcing water up from roots through xylem due to water entering root cells by osmosis
c) Translocation- transport of food in the plant via the phloem
34. What is the “sink-source model” & what does it explain? It is a model that explains how food is moved
from the leaves (source) where it is formed by photosynthesis to whatever structure in which it will be
used (sink), like fruit, stems, roots, etc.
Animals
35. What is asexual reproduction? Can it happen in animals?
Asexual reproduction is producing new organisms from one parent only. No new genetic combinations will
occur. Includes budding, fragmentation, and parthenogenesis in animals
36. Define:
a) Budding
b) Binary fission
37. Describe fertilization including the fast and slow block to polyspermy.
38. What do the following layers of the embryo eventually become?
a) Ectoderm- lining of digestive tract, lungs, liver, & other internal organs
b) Mesoderm- notochord, lining of the body cavities, muscles, bones, circulatory system
c) Endoderm- Integument and associated glands, nervous system
39. Tell what happens in these parts of the mammalian digestive tract:
a) Mouth- ingestion, mechanical digestion & the beginning of chemical digestion
b) Esophagus- tube that moves food from mouth to stomach by peristalsis
c) Stomach- receives food from the esophagus; chemical & mechanical digestion; pepsin digests proteins,
HCl acidifies the chyme (digested food)
d) Small intestine- final chemical digestion; absorption of lipids & proteins
e) Large intestine- absorption of minerals and water
f) Anus- opening of digestive tract to outside; waste exits from here
40. Tell what happens in the following digestive glands and ancillary structures
a) Salivary glands – omit
b) Liver- produces bile to help in the digestion of fats, detoxifies substances coming from the intestines,
stores sugars as glycogen and releases it when blood sugar levels fall
c) Pancreas- produces insulin to reduce blood sugar levels & produces glucagon to raise them
d) Gall bladder- stores & releases bile through the bile duct into the small intestines
41. What is the difference between an open and closed circulatory system?
A closed circulatory system keeps blood in blood the blood vessels and heart; an open one squirts blood
out over the organs & collects it in sinuses to return it to the heart.
42. Describe the flow of blood through a mammalian heart.
Inferior & superior vena cavae collect blood & pass it to the right atrium→ right ventricle→ pulmonary
artery→ (lungs) → pulmonary vein→ left atrium→ left ventricle→ aorta (to the body)
43. What is blood pressure? What is diastolic pressure? What is systolic pressure?
Blood pressure is the force blood exerts against the blood pressure walls. Systolic pressure is the highest
pressure in the artery & occurs when the ventricles contract. Diastolic pressure is the lowest pressure &
occurs when the ventricles are filling with blood.
44. Describe the flow of air through the mammalian respiratory system. Be sure to give the major structures
and tell what they do.
Nose & nostrils- take air in
Nasal cavities- clean, warm, & humidify the air
Pharynx- connects to the larynx
Larynx- the voice box, has the vocal folds air then flows through these structures:
trachea→ bronchi→ bronchioles→ alveoli (oxygen is absorbed into the blood from here)
45. The major components of blood are plasma, red blood cells, white blood cells and platelets. Tell what each
does.
Plasma- fluid portion of the blood, contains dissolved minerals, sugars, hormones, etc.
Red blood cells- carry oxygen to the cells & carbon dioxide from the cells
White blood cells- fight disease, mediate allergies
Platelets- help form blood clots, made from a cell that broke up
46. Describe the 3 lines of defense, briefly.
First line of defense- barrier defense; skin & mucous membranes
Second line of defense- nonspecific defense; inflammation, localized fever, antimicrobial proteins
Third line of defense-specific, humoral defense: lymphocytes (T and B cells) produces antibodies and
cytokinins
47. Differentiate between a primary and secondary immune response.
Primary immune response- First exposure to “nonself” proteins (antigens) requires 10-15 days for
lymphocytes to capture the antigens, take them to the lymph nodes & build antibodies specific for those
antigens. Also forms memory cells that will be able to immediately form antibodies against the same
proteins
Secondary immune response- In the second exposure to the antigen, immune system requires less time
to react. Memory cells immediately multiply and begin to produce antibodies; requires ~ 3 days.
48. Differentiate between active and passive immunity and tell what causes auto immune diseases.
Active immunity- body forms antibodies when it is exposed to the disease or a vaccination
Passive immunity- immunity acquired when one individual gives antibodies to another
49. Breifly describe the following:
a) Thermoregulation
b) Vasodialation
c) Vasoconstriction
50. Describe a nephron. Be sure to include the terms Bowman’s capsule, glomerulus, peritubular capillaries,
loop of Henle, and collecting tubule.
Blood flows from the renal artery into the kidney and is distributed to the nephrons. The nephron is the
functional unit of the kidney where blood is filtered and urine is produced. An arteriole takes blood to the
glomerulus, a knot of capillaries from which plasma is forced into Bowman’s capsule. Bowman’s capsule is
cup shaped structure that surrounds the glomerulus to receive the filtrate (plasma). The filtrate then proceeds
down the loop of Henle while the blood will go through the peritubular capillaries. The loop of Henle is a long,
tubular loop from which the peritubular capillaries will reabsorb proteins, salts, sugars, minerals, and finally
water. What is left in the loop is urine. The blood then flows on into the renal vein while the urine is collected in
the collecting tubule and will eventually flow into the urinary bladder for storage.
51. Define the following:
a) Motor neuron- outgoing from brain; connects to a gland or muscle to cause a response to a
stimulus
b) Sensory neuron- incoming to brain; brings information to the brain from sensory receptors like
the nerves in the skin or the ears & eyes
c) Interneuron- connects sensory nerve impulse to motor nerve to give a rapid response; seen
especially in brain & spinal cord
52. Define the following:
a) Axon- long, narrow extension of the nerve cell body that conducts the nerve impulse to the next neuron
b) Dendrite- short, incoming part of the nerve cell that brings in a nerve impulse to the cell body
c) Myelin sheath- lipid sheath around the axon that prevents a rapid loss of ions and thus speeds nerve
impulses; insulation; formed by fat containing Schwann cells
d) Node of Ranvier- gaps in the myelin sheath between the Schwann cells; signal is propagated when
depolarization at the nodes passes the impulse down the axon (signal propagation)
e) Neurotransmitter- chemicals released at synapse that trigger a nerve impulse in the receiving nerve cell
f) Synapse- a small space between the axon terminal of one neuron and the receptors on the dendrites of
the next one in the nerve.
53. Describe the passage of an nerve impulse down an axon.