BIO DAT Flashcards
1
Q
Energy can be put into two categories (DAT favorite!):
A
a) Kinetic: energy of motion (e.g. blood flows)
b) Potential: energy that is stored (e.g. glycogen)
2
Q
ATP allows
_____(endergonic/exergonic)_____ reactions to become
____(endergonic/exergonic)____.
A
Endergonic ——ATP—-> Exergonic
3
Q
If you radio-label a S atom, what would it most likely end up in?
A. Carbohydrate
B. Protein
C. Lipid
A
B. Protein
Proteins contain C, H N, O, S
4
Q
Which 3 amino acids are hydrophobic?
A
LIV “you need organic molecules to live”
Leucine
Isoleucine
Valine
5
Q
Which 3 amino acids are hydrophilic?
A
LAG
- “if you don’t learn this shit you’re gonna lag getting into dental school”
Lysine (contains NH bond) Aspartic acid (aspartate) (contains OH) Glutamic acid (glutamate( (also contains OH)
6
Q
How much free rotation do a polypeptide chain of amino acids have?
A
Very important DAT concept:
Very little
-Steric Hinderance cause the trans conformation to be more stable than cis
7
Q
What 2 important biological molecules does sugar-phosphate “backbone” form the structural framework for?
A
DNA and RNA
“Know that for the DAT, you may thank me one day!”
8
Q
What is the monomer of nucleic acids(many nucleotides) that connects the sugars of each nucleotide together?
A
Phosphodiester bonds
*nucleotides are linked together by phosphodiester bonds
9
Q
What two organs contain the most mitochondria?
A
Heart > Kidneys»_space;» everything else
10
Q
What 2 WBCs are loaded with lysosomes?
A
Macrophages and Neutrophils
-macrophages and neutrophils do a lot of phagocytosis
“Know that for the DAT, you may thank me one day!”
11
Q
What are the 3 sections of the Golgi and what occurs at each?
A
Cis golgi —> molecules go in
Trans golgi —> molecules go outward
Main golgi —> molecules get processed
12
Q
How and where are lysosomes formed?
A
lysosomes are formed by budding from the golgi complex
Budding: new individual splits off from existing one (hydra)
“A favorite DAT question”
13
Q
What are many of the cells polysaccharides made by/from?
A
Golgi and glycosaminoglycans of the extracellular matrix
14
Q
Part of which organelle is continuous (connected) with the nuclear envelope?
A
the Rough ER
“Know this for the DAT exam”
15
Q
What is the difference between heterochromatin and euchromatin?
A
Heterochromatin = not actively transcribing because it’s Condensed (Dark stained cells in DNA)
Euchromatin = is lighter color and actively transcribing cells in DNA because it’s loosely packed
(both are near the nuclear)
16
Q
What is the “mitotic poison” that messes up microtubules and halts mitosis?
A
colchicine
17
Q
What are cilia and flagella composed of?
A
microtubules and motor proteins used for movement
18
Q
What molecular motor enzymes can walk along microtubules and are responsible for the bending movements of cilia and flagella?
A
Dynein “walking” is responsible for the bending movements of cilia and flagella
and Kinesins
19
Q
What is the pattern of the flagella and cilia?
A
“9+2” array
microtubules are arranged in 9 pairs (mm-mm-mm-mm-mm-mm-mm-mm-mm)
you can observe this using a transmission electron microsope
“A sure bet to appear on the DAT!!!”
20
Q
What enzyme is used in the first step of glycolysis and what is the duty of this enzyme?
A
Kinase - catalyze the transfer of a phosphate group from a high energy molecule such as ATP.
“This is an important point”
21
Q
What type of enzyme can make a glucose into a fructose?
A
Isomerase - changes a molecule into its isomer
22
Q
What type of enzyme catalyzes rxns forming NADH and FADH2 from NAD+ and FAD+?
A
Dehydrogenase
“If you see NAD+, NADH, FAD, FADH2… you are most likely dealing with a hydrogenase”
“A must have name for the DAT exam”
23
Q
What is the bottom line thing you need to understand about what acetyl CoA does for us?
A
the TCA cycle dismantles acetyl groups converting them into CO2 and H- and H+ into the ETC to produce ATP
“essential to know”
24
Q
Acetyl CoA contains what functional group?
A
Thioester
25
What percentage of ATP is generated from the ETC?
90%
26
What does CoQ or Ubiqunione participate in?
lipid soluble carrier in the ETC
27
What mammals contain high amounts of myoglobin and what does this give them the ability to do?
Wales and Seals- contain a lot of myoglobin which allow them to hold their breath for an extended time under water
"This is a favorite DAT-type question!!"
28
Are globular protein hydrophobic or hydrophilic and are they H2O soluble?
Globular proteins = hydrophilic, water soluble
29
Myoglobin/ hemoglobin curves:
What is BPG and which way does it shift the Hb curve?
BPG (2,3-DPG) shift the Hb curve to the right
O2 dumps off more easily when BPG is around
Low pH = shift to the right = Hb dumped off O2
30
In Sickle Cell Anemia a glutamic acid is converted to valine; where on hemoglobin did the mutation occur?
hemoglobin B-chain
(beta-chain)
"A favorite DAT question!!"
31
What is the duty of Kinetichores?
kinetichore- a protein structure attached to the centromere that links the sister chromatids to the mitotic spindle
32
If 2N = 4,
how many chromosomes are there at metaphase?
how many chromatids?
how many chromosomes are there at anaphase?
how many chromatids?
Metaphase: 4 chromosomes, 8 chromatids
Anaphase: 8 chromosomes, 7 chromatids
33
What are the definition of:
```
Somatic cells:
Gametes:
Genome:
Aster:
Spindle:
Zygote:
```
Somatic cells: all cells except reproductive cells
Gametes: eggs or sperm cells
Genome: the genetic info in a cell
Aster: an array of microtubules that extends from each centrosome
Spindle: made up of proteins and microtubules; the spindle includes centrosomes, asters and microtubules
Zygote: fertilized egg cell (2N)
34
Deuterostomes include: (2 examples)
Protostomes inclue: (3 examples)
Deuterstomes: first opening forms the anus
(chordates and echinoderms)
Protostomes: first opening forms the mouth
(mollusks, arthropods, and annelids)
35
What does the notochord in humans become?
a gelatinous disk found between vertebrae
36
Even though Tunicates and amphioxus are classified as chordates, they are ______________.
invertebrates
37
The wing of a butterfly and the wing of a bird represent ____________ structures.
analagous
38
What are the important bacterial diseases I should know for the DAT?
GLASSS
```
Gonorrhea
Leprosy
Anthrax
Sepsis
Syphilis
Salmonella (food poisoning)
```
39
What is Mycology?
the study of fungi
40
What is a lichen?
the mutualistic association of a fungus and cyanobacterium or photosynthetic alga such as green algae
41
If you see "mycetes" on the DAT, what are you most likely dealing with?
Fungi = mycetes
42
What are the 2 endosymbionts?
mitochondria and chloroplasts cause they have their own DNA
43
A nucleic acid is a ______ made from monomeric units called _________.
A nucleic acid is a ___polymers___ made from monomeric units called ___nucleotides______.
44
Which famous experiment concluded that DNA and NOT protein is the actual genetic info?
Hershey-Chase experiment
45
What famous experiment concluded that *DNA* from a dead pathogenic bacteria could cause non-pathogenic bacteria to *transform* into pathogenic bacteria?
Fed-Griffith Transformation Experiment
46
Which famous experiment confirmed that DNA is indeed genetic material?
Avery-McCarty-Macleod Experiment
47
Why does alkaline conditions partially denature (i.e. unwinds DNA in certain areas) the helix?
Increasing pH causes deprotonation resulting in negatively charged atoms the repel away from each other, which is what causes the unwinding
48
Would the regions that unwind be richer in A = T or C ≡ G? Why?
Between A = T and C ≡ G the H-bonds help to “counter” the unwinding, but since C ≡ G has three H-bonds it will be stronger than A = T since it only has two H-bonds, thus a region richer in C ≡ G would unwind to a lesser extent. The area that unwinds clearly has more A = T content.
49
What is the difference between missense mutation and nonsense mutation?
Missense mutation: wrong amino acid made
Nonsense mutation: if a stop codon is made
50
When is the only time E. coli can use lactose as an energy source?
When lactose is present and glucose levels are low
51
What is bottom line what the lac operon is?
the Lac operon is under dual control:
1. negative control by lac repressor protein
2. positive control by CAP
alot of AMP _---> CAP ---> promoter
52
If a normal male and colorblind female have a child, what is the possibility of the child being color blind?
50%
100% of boys
0% for girls but still are carriers
53
A hemophiliac male and a carrier female for hemophilia have a child. what is the probability to have a boy who is normal?
50% boys
50% of girls also have anemia
"DAT favorite"
54
What are important points to remember about sex-linked gene inheritance?
Males give sex-linked genes to their daughters..... not their sons
Males only give sons Y chromosome
Females give sex-linked genes to both sons and daughters
A male gets a sex-linked disease from his mother!!!
55
How many gametes can be made given the following genotype: Xx Yy Zz WW BB
2^n = total gametes
2^3 = 8 total gametes
"The DAT loves this type of problem"
56
Which WBCs are usually the "first responders" to appear in acute bacterial infections?
Neutrophils = first line of defense against invading microorganisms
57
Rank the following from most abundant to least abundant:
RBCs, Platelets, WBCS
RBCs > Platelets > WBCs
"Know this for the DAT"
58
How many heart chambers do mammals, birds, reptiles, amphibians, and fish each have?
-Mammal and birds = 4 chamber hearts
- Reptiles and amphibians = 3 chamber hearts
* except for alligators, which have 4 chambers*
-Fish = 2 chamber hearts
"A must know for the DAT"
59
Which 2 VEINS are the only ones that carry oxygentated blood?
Pulmonary vein and Umbilical vein
60
What are the distinguishing features of bone?
the ground substance and its extracellular matrix of collagen
61
What is the difference between the axial skeleton and appendicular skeleton?
Axial = skull, ribs, vertebre, sternum (breastbone)
Appendicular = all the appendages (arms, legs etc.)
62
A human hand, dogs leg, birds leg and whales fin are all considered _________________ structures.
The wing of a butterfly and the wing of a bird represent _____________ structures.
Homologous- body parts that resemble one another in different species from common ancestor.
Analogous- body parts that resemble one another in different species because they evolved independently as adaptation to their environments.
"Important for DAT"
63
What is a prophage?
a prophage is a bacterial phage that has become integrated into the bacterial chromosome
64
What is the difference between obligate anaerobes, obligate aerobes and facultative anaerobes.
Obligate anaerobes: killed by O2
Obligate aerobes: need O2 to grow
Facultative anaerobes: prefers O2 if available, but could switch to fermentation if needed
"Important definitions for the DAT Exam"
65
What is the difference between a photoautotroph and chemoautotroph, photoheterotroph, chemoheterotroph?
Photoautotroph: synthesizes organic molecules using light
Chemoautotroph: seen in prokaryotes, inorganic substances are its energy source (no light needed!!!)
Photoheterotroph: light is needed for ATP production, BUT gets their carbon from various organic sources
Chemoheterotroph: energy is obtained from organic compounds. (Bacteria, fungi, most protist , animals are here!!!)
66
What is a detritivore?
a classification of decomposers
67
What blood type have no A or B antibodies?
AB
68
What blood type has both A and B antibodies?
type- O
69
What blood type has no antigens present?
type- O
70
What are 3 important X-Linked diseases?
1. Color blindness
2. Hemophilia
3. Duchenne Muscular Dystrophy
71
What does Aneuploidy mean?
offspring with wrong number of chromosomes (Down Syndrome)
72
What do these syndromes result from?
Differentiate between:
- Down syndrome
- Turner syndrome
- Kleinfelter Syndrome
Down syndrome: extra chromosome (trisomy 21) mental retardation
Kleinfelter syndrome: male w/ XXY (men who act gay)
Turner syndrome: female w/ only 1 X chromosome (monosomy)
73
What is polyploidy and where is this commonly seen?
common in plants; they can be 3N or 4N cell
seen in weeds and dandelions
74
How many gametes can be made given the following:
| Xx Yy Zz Ww BB
of gametes = 2^n
2^3 = 8
Where did the 3 come from?
-there are only 3 heterozygotes, thus n = 3
"The DAT loves this type of problem!"
75
Where does gas exchange take place in humans?
alveoli
76
What is bradycardia vs tachycardia?
bradycardia: decrease heart rate
tachycardia: increase heart rate
77
What germ layer(s) is the epidermis and dermis of skin?
Epidermis = Ectoderm
Dermis = Mesoderm
78
A function of osteoclast is the breakdown of bone. The breaking down of bone can also be referred to as bone ___________.
resorption
79
An endocrine gland secretes a _____1____, it travels through the ___2____ to its target site. At the site, the hormone enters the cell by ______3______ the cell membrane. The hormone binds to a receptor and it likely enters the nucleus. In the nucleus, activation of ______4_____ synthesis occurs. mRNA can enter the _____5_____ and make proteins.
1. hormone
2. blood
3. entering through
4. mRNA
5. cytoplasm
80
What is the function of Calcitonin?
increase osteoblast activity and decrease osteoclast (bone formation)
81
Aldosterone is made along with the lesser hormone _______________________.
deoxycorticosterone
82
What is the duty of Aldosterone?
to stimulate the kidney cells to reabsorb Na, thus increasing blood pressure
(increase blood volume = increase pressure)
83
Amphibian lungs, when present, are __1___ are ___2__ a very effective gas exchange mechanism. As a result, amphibians have to heavily rely on ____________**_3_**_________ such as skin to carryout gas exchange.
1. small
2. NOT
* 3. gas diffusion across body surfaces*
"Favorite DAT type question"
84
What 2 main areas of the brain control breathing?
Medulla Oblongata and Pons
85
As metabolic activity goes up (working out), the CO2 in the blood ____1____ as _____2____ is produced, hence the pH is _____3______. The Medulla will respond by _____4____ the breathing rate.
1. increases
2 lactic acid
3. lowered
4. increasing
"Very important concept here peeps!"
*** notice how ONLY CO2 has the effect on breathing control centers, NOT O2***
86
What do gap junctions connect together?
the cytoplasms of 2 cells
"Remember for the DAT"
87
What percentage of the cytoplasmic volume does mitochondria take up?
40%
88
What does Ca++ complex with?
Calmodulin: calcium-binding protein, which is involved in muscle contraction
89
Which is rich in mitochondria, myoglobin, oxidative enzymes and blood supply?
Red muscle fibers/ White muscle fibers
RED
90
What are myofibrils composed of?
thick and thin filaments
myosin = thick
actin = thin
91
What does the filament arrangement create a pattern of?
light and dark bands
Dark bands = A bands
Light bands - I bands
"Favorite DAT question!"
92
What is the structural and functional unity of myofibril?
Sarcomere
*DK DAT*
"Be clear on the fact that the sarcomere is the part of the myofibril between two Z lines"
93
What are Titin and Nebulin involved in?
they contribute to the stability of sarcomeres
Titin: helps position thick filaments
Nebulin: helps stabilize the thin filaments
94
What is myofibrils structural organization largely maintained by?
nebulin, titin and a-actinin
"Know that much... you will be sitting pretty for the DAT!"
95
The sarcoplasmic reticulum releaes ___1____ through *____2____-____2___* Ca++ release channels and enter the ___3___ to ___4__ to _____5_____.
1. Ca++
* 2. Voltage-gated*
3. cytosol
4. bind
5. troponin
"A favorite DAT question"
96
Approximately how many neurons are in the human body?
100 billion neurons
97
What is the purpose of the blood brain barrier?
to protect the brain from toxic substances and pathogens
98
What is between the arachnoid and pia matter of the brain and what does it contain?
subarachnoid space---> contains cerebral spinal fluid
99
The left hemisphere of the brain controls the ______ side of the body and vice versa.
Right side
100
What is the link between the endocrine system and nervous system?
the Hypothalamus
"A favorite test question from teachers"
101
Where is the white matter of the brain located and what is it's duty?
white matter lies underneath gray matter and is the
*relay and communication center* of the brain
102
List these in order from outermost layer and innermost layer:
Dura mater, Pia matter and arachnoid matter:
"DAP"
Dura
Arachnoid
Pia
103
What is meningitis?
Inflammation of meninges in the brain and can be ***bacterial*** or viral
usually involved with arachnoid and pia matter of the brain
104
What links the nervous system to the endocrine system?
hypothalamus
*DAT*
105
What were the first 2 primitive fish and what phylum are they in?
Agnathans
"Make sure you know these two fish are from class Agnatha and were the first fish... you might thank me one day"
106
What is the Thalamus?
a "relay station" in the brain
107
Dorsal is to _______ as Ventral is to ____________.
Dorsal = sensory
Ventral = motor
"Know the names Dorsal (sensory) and Ventral (motor) for the DAT!!"
108
Recall that in response to a stimulus, the membrane potential becomes less negative. What do we call this?
Depolarization
Depolarization = more positive/less negative
"KNOW THE DIFFERENCE BETWEEN HYPERPOLARIZATION FOR THE DAT"
109
If the resting membrane potential became more negative, we call this:
Hyperpolarization
"ie more polar" "more negative = more polar"
```
HYPER = MORE NEGATIVE
DEPOLERIZATION = MORE POSITIVE
```
110
When the Na+ channels open, Na+ goes ___inward/outward___ during _________.
Inward, depolarization
111
When is hyperpolarization caused by?
K+ channels open
1. K+ outward
2. Cl- inward
*Donavin DAT*
112
Glomerular filtrate contains all of the same substances as ___________ EXCEPT for the __________ which the filtrate lacks.
blood plasma
large proteins
113
What is the pathway of the nephron in order?
"Gay Boys Pick Little Dicks Cause Rick Used too"
1. Glomerulus
2. Bowman's capsule
3. Proximal tubule
4. Loop of Henle
5. Distal tubule
6. Collecting duct
7. Renal pelvis (innermost hollow chamber of kidney)
7. Ureter
"Commonly asked exam question. Know the order of this path"
114
What hormone decreases during alcohol consumption?
ADH- cause it regulates water balance, thus water is not returned, but you end up urinating more!
115
What autonomic nervous system is the afferent arteriole under control?
Efferent arteriole?
Sympathetic Nervous System = Afferent
"Know the central control points"
116
What is the rate of glomerular filtration directly proportional to?
Filtration pressure
117
What happens to Glomerular hydrostatic pressure, Filtration rate and Volume of urine flow/ouput if the Afferent arterioles are constricted compared to the efferent arterioles?
Afferent arterioles = Decrease
Efferent = INCREASE
"KNOW THIS FOR DAT"
118
Marine fish are _____1____ to their environment, drink ____2_____ and barely _____3_____.
1. hypotonic
2. alot
4. urinate
"Favorite DAT problem"
119
Why do women tend to get urinary tract infections more than men?
Bacteria can reach the bladder of women far more easy than men. The urethra is shorter in women, which means bacteria have a much shorter distance to travel.
"Favorite DAT-type problem"
120
Describe the alternation of generations for land plants in regards to meiosis and mitosis?
A diploid sporophyte becomes a haploid spore via meiosis
A haploid gametophyte becomes a haploid gamete via mitosis
121
What is the sequence of events in the human life cycle?
"Girls Fuck Clean Guy's Nipples"
1. Gametogenesis
2. Fertilization
3. Cleavage
4. Gastrulation
5. Neurulation
122
A primary oocyte is _____ and a secondary oocyte is ____.
Primary oocyte = 2n (diploid)
Secondary oocyte = n (haploid)
ovum/egg = n
"This is a common exam question!!"
123
List all three phases of the female reproductive system in chronological order:
Explain the difference between the Proliferative and Secretory Phases of the female reproductive system:
Proliferative (Follicular) Phase: days 4-14
- enlargement of arteries and uterine glands
- reconstruction of connective tissue, new epithelization n
occurs
- endometrium fully restored on 14th day
Secretory (Luteal) Phase: day 15-28
- begins after ovulation
- endometrium thickens
* progesterone levels @ its highest*
Menstrual phase--> Proliferative---> Secretory
"Both names of proliferative and secretory need to be learned for the DAT"
124
What are the 3 duodenal hormones and what is each of their duties?
"Gastrin Sucks Cock"
Gastrin: triggers secretion of HCl by parietal cells (histamine and acetylcholine also do the same thing)
Secretin: Stimulates HCO3- (bicarbonate) release from pancreatic fluid.
Cholecystokinin (CCK): stimulates gall bladder contraction
"Know these three for the DAT, a sure bet"
125
From the villi, nutrient rich blood enters the ____2____ _____2____ ___2__ that goes directly to the ____3___ then _____4____.
1. Villi *(one cell thick)*
2. hepatic portal vein
3. liver
4. organs
"Know this path for the DAT!!!"
126
Which organ has both endocrine and exocrine functions and is known as the "dual organ"?
Pancrease
127
What enzyme does pancreatic juice contain that the DAT loves to ask about?
Proteases (trypsin, chymotrypsin, procarboxypeptase)
"favorite DAT question"
128
What enzymes are stored as zymogens and what activates them?
Why is it important that these enzymes are stored as zymogens and need to be activated?
Trypsin and Chymotrypsin are stored as zymogens and are activated by *enterokinase*
"This is important. Why? It prevents the pancreas from digesting itself"
"DK DAT"
129
Which artery(s), vein(s) control the blood supply of the liver?
Hepatic = LIVER (2 veins, 1 artery)
(Hepatic) Portal vein: transports blood from Villi to Liver
Hepatic vein: transports deoxygenated blood away from
Liver to inferior vena cava
Hepatic artery: carries oxygenated blood to Liver
"Very important vessels to know for the DAT"
130
What cells in the liver are responsible for the processes gluconeogenesis and deamination, that converts lipid and amino acids into glucose?
Hepatocytes of the liver
hepatocytes are large polyhedral cells that are multinucleated
liver cells are highly aneuploid (extra/fewer chromosomes than normal)
131
What part of the digestive system absorbs about 90% of the water from GI tract?
small and large intestines
132
What does the term ruminant refer to?
cows or goats that are able to digest cellulose
133
What type of aerobes are the bacteria in the large intestine?
Obligate anaerobes
134
Where are hormones secreted, do they target specific cells, and are they fast acting or slow,?
Hormones are secreted in the blood, highly specific, and are slow acting cause they remain in the blood for a few seconds to a few hours.
"Favorite DAT question"
135
Describe the difference between Endoderms and Ectoderms?
Endoderms: (homeotherms)
- "warm-blooded" (warmed by metabolism)
- Birds and mammals
- more mitochondria
- usually require more food due to higher metabolism
Ectoderms: (Poikilotherm)
- "cold-blooded" (warmed by external sources; environment)
- Reptiles, fish and invertebrates
- can tolerate temperature changes
"A favorite DAT topic!"
136
Why do smaller animals have a higher breathing rate, heart rate, and blood volume than larger animals?
Because they have higher *per-gram* basal metabolic rates than larger animals
137
What 2 specialized tissue do vascular plants contain?
Xylem: contains cells that die at maturity called tracheids that transports water in one direction (root-->leaves)
- xylem is what makes up wood
Phloem: caries sugars from leaves--> rest of the plant
Xylem transports *up*
Phloem transports *down*
138
On the roots of legumes such as peas and beans, we see swelling called ___________, that contain nitrogen-fixing bacteria which convert atmospheric N2 into NH3 for the plant to use.
root nodules
139
What are the differences between monocots and dicots?
Monocots:
- single cotyledon
- long narrow leaf
- parallel veins
- scattered vascular bundles
- floral parts are in multiples of 3
Dicots:
- two cotyledon
- broad leaf
- network of veins
- ring of vascular bundles
- floral parts are in multiples of 4 or 5
140
What are the male and female parts of plants?
Male = stamen:
- anther
- filament
Female = carpel:
- ovary (eggs develop, fertilization occurs, seed matures)
- style
- stigma
141
Describe the duties of the petal, sepal, and ovule in a plant:
petal: attracts pollinators
sepal (calyx): offers protection for plant
ovule: consists of an egg that becomes the seed
142
Why are ferns unique plants?
they use spores, NOT seeds. Ferns have *no flowers* (sporophyte)
thus, moss and ferns are major plant types that have no flowers, no seeds, but reproduce by spores.
"This is a major concept, and hopefully you will not forget this."
143
Explain the difference between:
- populatin
- habitat
- ecosystem
- community
Population: group of individuals of the SAME species
Habitat: place where a population lives
Ecosystem: represents all the organisms present in a particular area and their physical environment
Community: group of populations that are comprised of DIFFERENT species in an area
"DAT loves these"
144
What is the difference between primary and secondary succession?
```
Primary succession:
occurs when the terrain was without life, or almost so. ***The soil has NOT formed.***
- a new volcanic island
- lava flows
- glacier retreats
- sand dunes
- pioneer organisms (lichens, moss)
- takes a long time for area to colonize!!!!
```
Secondary succession:
series of community changes occur in disturbed areas that have not been totally stripped of their vegetation or soil.
- existing community has been cleared by disturbance such as a fire
- faster than primary bc ***soil already exist***
"The DAT loves these terms- know the difference!!!"
145
What causes global warming?
humans increasing the amount gases makes the planet warmer
146
The air we breathe is mostly ________ and the earths crust is mostly ________.
Air we breath = N2
Earth's crust = O2
"For the DAT... I advise you to remember two things"
147
What factors can affect sustainable population size?
1. predation (the prey of a predator)
2. competition
3. available resources
4. pollution
5. disease
***whenever a population shows uniform dispersion this suggests a *competition* among members***
***when a population grows its density increases and so does competition for its resources, predation, wastes, parasitisms, and diseases.
These are DENSITY-DEPENDENT factors***
"Common DAT type problem!!"
148
Populations grow exponentially when...
birth rate is slightly above the death rate and both rates are constant as well as immigration and emigration
it is obvious that decreasing human birth rates would be most helpful to solving the world's environmental problems.
"Bottom line for the DAT"
149
What is the difference between r-strategist and k-strategist
r-strategist = HIGH growth rate with many offspring
* exponential growth model*
- little parental supervision
- short life spans
eg. insects, bacteria, diatoms, rodents, weeds, diatoms
k-strategist = LOW growth rate with few offspring
* logistic growth model*
- mammals
- much parental care
- more stable environment is occupied
- more stable and energy efficient
(could be a DAT question showing a curve that shows a low percentage of living organisms = humans)
"Know the difference between these 2 strategies for the DAT"
150
What is the difference between a fundamental niche and realized niche?
Fundamental niche = theoretical niche in which no limiting factors are present (no disease, no predators etc.)
Realized niche = the niche that is actually occupied by the organism
"Know this for the DAT!"
151
What is the difference between symbiosis, mutualism, commensalism and parasitism??
Symbiosis is simply a relationship (ecological) between organisms of different species living in a community. ***Neither help or harm each other (neutral)***
[symbiosis organisms living in the same "sym" biome "biosis"]
Mutualism = both organisms benefit (eg. bacteria make vitamin K in the human intestine)
Commensalism = One organism benefits while the other is NOT effective (eg. barnacles living on whales)
Parasitism = One organism benefits while the other is harmed (eg. blood fluke infects a human and causes enlargement of the liver and spleen in addition to other disorders)
152
What happens over time in a community where two species compete for limited resources?
population density declines
"DAT favorite"
153
What is interspecific competition and what are the 2 types?
interspecific competition: different individuals of a species compete for a resource that limits their growth and survival (eg. fox and lynx compete for same prey)
1. Interference competition: eg. corals kill other corals by poisoning them; birds chase other birds away
2. Exploitation competition: both species have equal access to a resource but one exploits it faster
"This is a DAT favorite!"
154
What can occur if predators can keep prey populations from overshooting its carrying capacity?
a Stable Coexistence
155
What are Aposematic signals?
Aposematic signals = WARNING signals
| eg. a skunk's stripes
156
What is a mimic and what are the 2 mimics I need to know for the DAT?
mimic: a species has the same or similar appearance of another
Batesian mimicry: we see deception!!! (a harmless organism "pretends" that it's dangerous by looking like a poisonous organism
Mullerian mimicry: groups of organisms that resemble one another but DO contain harmful defenses (eg. bee's black and yellow stripes)
157
The more species you have, the ___more/less___ evenly distributed they are. Often, the more species, the ___more/less___ stable the community is.
More species
More stable
158
Categorize each of the following in the food chain below as:
dandelions--->snail--->frog--->bird--->fox
1. primary producer
2. primary consumer
3. secondary consumer
4. tertiary consumer
5. qauternary consumer
dandelion = primary producer (autotroph)
snail = primary consumer
frog = secondary consumer
bird = tertiary consumer
fox = qauternary consumer
159
Organism such as soil arthropods and earthworms ingest dead plants or animal tissue are referred to as:
Ditritivores
Detritus: dead plant or animal tissue
160
What is denitrification, which organs do it and how do they do it?
denitrification lowers soil fertility and decreases agriculural productivity.
bacteria such as pseudomonas and bacillus
* this is done under anaerobic conditions*
* Always a trick question"
161
What happens to the surroundings temperature there is an endothermic process?
exothermic?
Endothermic = surroundings get cool
Exothermic = surroundings get warm
"DAT favorite question, no need to thank me..."
162
Deserts are located in what is called a ____________.
Rain shadow
163
Describe each of the biomes:
- Tundra (arctic, alpine)
- Taiga
- Coniferous forest
- Temperate deciduous forest
- Tropical rain forest
- Desert
- Savanna
- Chaparral
- Grass land
Tundra (arctic, alpine) = COLDEST
- arctic: 10 > inches of rain a year
- alpine: Coldest
Taiga = LARGEST terrestrial biome (apart from oceans)
- also called "Boreal forest"
- most animals have furs to protect them from the cold
- eg. New York
Coniferous forest
- SAME as Taiga
Temperate deciduous forest = VERY FERTILE soil
- season appearance and disappearance of *canopy*
- deciduous means falling off or at a certain season
Tropical rain forest = HIGHEST DIVERSITY of animals and plants
- produces 40% of Earth's oxygen
Desert = less than 10 inches of rain
- plants have to adapt to weather (plants store water safer)
- Sahara is the hottest desert in the world
Savanna = transitional biome
- in between a forest and desert
- Ungulates: animals with hooves (elephants)
Chaparral = has both forests and grasslands
- small, hard leaves
- 15 inch of rain a year
- more rain than deserts
Grass land = RICHEST SOILS in the world
- 25 inch of rain a year
164
What is the difference between biotic and abiotic when dealing with biomes?
Biotic = pertaining to LIVING organisms (behaviors and interaction)
Abiotic = pertaining to NON-living organisms (abiotic factors include sunlight, soil, temp, and water)
165
what is the largest biome in the world?
Marine biome = 70% of earth
166
What is an estuary?
Estuary: where freshwater and saltwater merge
eg. where a river meets an ocean
167
In the winter and summer which level (top/bottom) has the highest O2?
O2 is HIGHEST at the TOP
O2 is LOWEST at the BOTTOM
"Know this for the DAT and you'll be fine"
168
What does "imprinting" describe when talking about animal behavior?
Imprinting is done rapidly and must occur during a definite critical period after hatching!!!
"Almost a sure bet DAT question peeps!"
169
What does "Habituation" describe when talking about animal behavior?
Habituation
eg. if you keep bothering an ant and not actually hurting it then it will stop responding to your stimulus
eg. a clock makes a good ticking sound, but after a while you pay less and less attention to it.
Habituation = NON-associative learning...
in other words, there is no reward or punishment associated with it
"Make sure you know this for the DAT... and you are sitting pretty!"
170
The defining characteristic separating one species from another is that they are ___________ isolated.
Reproductively isolated
"Favorite DAT-type question" (DK DAT)
171
What is the difference between allopatric and sympatric speciation?
Allopatric speciation = geographic barrier emerges between species
Sympatric speciation = speciation that occurs w/o geographic barrier
eg. flies used to lay their eggs on hawthorn trees, but for the last 200 years they began to start laying their eggs on apples. Thus a new species emerged known as apple maggot flies
"For the DAT make sure you are clear between allopatric and sympatric speciation"
172
Certain times in our history have seen the elimination of major life forms. The dinosaurs disappeared at the end of the ____________ era is a great example!!!
Mesozoic = dinosaurs
"A must have fact for the DAT!!"
173
What is the age of the earth?
When did first prokaryote that emerged?
When did first eukarote that emerged,
earth = 4.5 billion yrs ago
prokaryote = 3.8 billion yrs ago
eukaryote = 2.7 billion yrs ago
174
What did Charles Darwin mainly write about?
| natural selection is not the answer
Adaptions
175
What did Jean-Baptiste Lamarck study and what theory did he come up with and why was it wrong?
studied fossils; "
Theory of Acquired Characteristics"
The theory is wrong b.c it states "If an organism changes in order to adapt to the environment, these changes are passed down to offspring"
eg. The father works out and becomes very muscular so if he has a son, his son will also be muscular
"VERY IMPORTANT" (DK DAT)
176
What is the difference between Homologous and Analogous structures?
Homologous = structure w/ similar morphology and different function b.c. they came from a common ancestor (they can look different)
eg. flipper of a whale
eg. wing of a bat
eg. leg of a cat
eg. arm of a human
Analogous = structures w/ similar function but NO common ancestor
eg. wing of a bat and wing of a bird
eg. wing of an insect and the wing of a bird
eg. fish fins and whale flippers
eg. jointed legs of insects and vertebrates used for locomotion
eg. the spine of a cactus and thorn of a rose
"This is a must have for the DAT exam"
177
What is the difference between divergent and convergent evolution?
Divergent evolution = common ancestor
Convergent evolution = NO common ancestor
178
What are the 5 Hardy-Weinberg conditions?
1. Large population (gene frequency doesn't change as a result of chance alone)
2. Random mating (inbreeding causes little mixing of genes)
3. No mutations (mutations modify our gene pool)
4. No natural selection (survival differences can alter gene frequencies)
5. No gene flow (immigration, emigration)
- according to the Hardy-Weinberg principle, the genotypes and allele frequency in a given population remain constant
"This is important to know for the DAT exam!!!"
179
Let us consider a population on a small island of only 50 people.
If an allele y is carried by a certain individual who either ***failed to mate*** or ***gotten killed***, allele y would be completely lost. This is a ________ _______. This is clearly a microevolutionary process. Thus, the change in allele frequencies in a gene pool of a small population arising from ______ events is called genetic drift.
Genetic drift
chance
small population = large effect
"Know this for the DAT!! You will thank me."
180
What is the term "fitness" refer to when talking about biology?
the contribution that an organism makes to the gene pool of the next generations; number of fertile offspring
"This is an important point to remember for the DAT exam!!!"
181
What is the difference between stabilizing selection, directional selection, disruptive selection and sexual selection?
Stabilizing selection = alleles that produced uncommon phenotypes are eliminated over time (undo the effects of gene flow, mutation, or genetic drift)
eg. babies smaller or larger than the range of 6.5-9lbs
Directional selection = allele frequencies shift due to changing conditions in the environment
eg. insecticide "FAVORITE DAT-TYPE QUESTION"
Disruptive selection = when an extreme trait improves fitness, it is selected
Sexual selection = helps you find a mate to reproduce but doesn't provide any survival benefits
182
What was the Miller-Urey experiment?
Bottom line, it showed that abiotic (non-living) synthesis of organic molecules are possible.
***The Urey-Miller experiment did NOT produce any nucleotides***
Life needs 2 key properties:
1. Metabolism
2. Replication mechanism
"For the DAT know this"
183
What was early Earth's atmosphere comprised of?
CO2, CH4, NH3, H2S, and H2
184
Place animals in the correct era:
- Cenzoic era
- Mesozoic era
- Paleozoic era
Which era had the largest mass extinction in history?
Cenzoic = mammals (most recent)
Mesozoic = reptiles (dinosaurs)
Paleozoic = fish and land plants
Paleozoic era ---> largest mass extinction (90% of all marine animal species)
"Question on DAT about mesozoic era"
185
What is the difference between isometric growth compared to allometric growth?
Isometric growth = all body parts grow @ the same rate
Allometric growth = body parts do NOT grow @ same rate
eg. human growth
186
What are marsupials?
Kangaroos
