Past Exams Flashcards
(141 cards)
1
Q
What type of data is used to construct phylogenetic trees?
A
Morphological, molecular, and genetic data
2
Q
In a phylogenetic tree, a branch point (node) represents:
A
A common ancestor shared be descendant species
3
Q
Which of the following is an example of homologous structures?
A
The flippers of a whale and the arms of a human
4
Q
Why can’t individuals evolve?
A
Individuals cannot change their DNA, but populations change over generations
5
Q
Why does evolution not produce perfectly adapted organisms?
A
n selection only acts on existing variations, environmental conditions constantly change, and there are trade-offs in traits that may prevent perfection
6
Q
Which of the following is an example of natural selection?
A
Antibiotic-resistant bacteria becoming more common in hospitals
7
Q
Which of the following best describes how genetic variation is generated?
A
Through both mutation and recombination in meiosis
8
Q
Which of the following is NOT a condition of Hardy-Weinberg equilibrium?
A
Small population size
9
Q
What does the variable “p” represent in the Hardy-Weinberg equation?
A
The frequency of the dominant allele
10
Q
Genetic drift has a stronger effect on:
A
Small populations
11
Q
Founder effect
A
A new population started by a small group from a larger population
12
Q
Stabilizing selection
A
Birds with very short or very long wings are less likely to survive
13
Q
Directional selection
A
A species of finch evolving progressively larger beaks due to seed availability
14
Q
Disruptive selection would most likely occur in which situation?
A
Medium-sized fish being outcompeted by both large and small fish
15
Q
Which helps maintain genetic variation in a population?
A
Gene flow between populations
16
Q
Example of a vestigial structure
A
The tailbone in a human
17
Q
Why can’t natural selection produce perfect organisms?
A
Environments change over time, mutations are random and not goal-oriented, there are always trade-offs between traits
18
Q
Gene flow differs from genetic drift because:
A
Gene flow increases genetic diversity while genetic drift reduces it
19
Q
What is the primary reason evolution does not stop?
A
Mutations, environmental changes, and genetic recombination introduce new traits
20
Q
Example of evolution driven by a shared environment?
A
Dolphins and sharks both evolving streamlined bodies for efficient swimming
21
Q
Best distinguishes microevolution from speciation
A
Microevolution involves changes in allele frequencies within a population, while speciation results in the formation of new species.
22
Q
NOT an example of microevolution?
A
The divergence of finch species in the Galápagos Islands, compared to the spread of antibiotic resistance in bacteria. the development of different fur colors in a population of rabbits over generations, and changes in allele frequency due to natural selection.
23
Q
Which of the following is an example of a prezygotic barrier?
A
Two species of crickets that have different mating calls
24
Q
Which of the following is NOT a prezygotic barrier?
A
Hybrid breakdown
25
Which of the following is an example of temporal isolation?
Two species of frogs that mate in different seasons
26
Which of the following describes a postzygotic barrier?
Offspring of two different species of salamanders fail to develop properly.
27
Example of hybrid sterility?
A mule, the offspring of a horse and a donkey, cannot reproduce.
28
Hybrid breakdown occurs when:
Hybrid offspring are fertile, but their descendants have reduced fertility
29
Which of the following geological events is most likely to lead to allopatric speciation?
The formation of a mountain range separating a population
(allopatric means geographically separated)
30
How can continental drift contribute to speciation?
By causing populations to migrate into new habitats with different selection pressures
31
How might reproductive barriers evolve in an isolated population?
Random mutations and natural selection can lead to changes in mating behavior.
32
Which of the following is NOT an example of allopatric speciation?
A new species of fish arises within a single lake without a geographic barrier.
33
Sympatric speciation differs from allopatric speciation in that
It does not require a geographic barrier.
34
Which of the following is an example of sympatric speciation?
Some apple maggot flies begin using a new host plant and become reproductively isolated.
(sympatric is when one species originates from another in the same location)
35
How can sexual selection contribute to speciation?
It can create differences in mate preferences that lead to reproductive isolation.
36
Which of the following is an example of sexual selection leading to speciation?
Birds of paradise developing elaborate courtship displays that differ between populations
37
Why are islands often hotspots for speciation?
They provide unique ecological niches and physical separation between populations.
38
What is a hybrid zone?
A region where interbreeding occurs between two species, sometimes producing hybrids
39
What is a possible outcome for species in a hybrid zone?
Reinforcement of reproductive barriers, the formation of a new hybrid species, fusion of two species into one
40
What would likely happen if two species in a hybrid zone experience extreme reproductive barriers?
Leads to fewer hybrids over time.
41
Which of the following best explains how radiometric dating determines the absolute age of a fossil?
It compares the ratio of stable to unstable isotopes in a fossil.
42
If a fossil is found in a rock layer below another rock layer containing a fossil of a known age, what can be inferred about the fossil’s age?
It is older than the fossil in the upper layer.
43
Which typical event marks the boundary between the era's of geologic time?
A mass extinction of species on Earth.
44
Broadly speaking, life on Earth
is relatively new.
45
Which of the following is a direct result of plate tectonics?
Earthquakes and volcanic activity along plate boundaries.
46
Pangea separated around 200 million years ago. What type of isolation did this create among species that might once lived close to one another?
Geographical
47
What is the primary goal of taxonomy in biology?
To specifically describe, name, and classify living organisms based on shared characteristics.
48
The categories of classification (species, genus, family, etc.) in systematics is arranged in which manner?
From broad to more specific
49
Which of the following best defines a clade? (connection from a cladogram or phylogentic tree)
A group of species that share ancestral traits and are considered more closely related.
50
Which of the following correctly lists the three domains of life?
Archaea, Bacteria, Eukarya
51
Each cell in the human body is bathed in blood, allowing exchange of materials in and out of the cells.
True
52
Hierarchical levels of organization in an animal’s body from smallest to largest
Cell → Tissue → Organ → Organ System → Organism
53
Which of the following correctly pairs a tissue type with both its structure and function?
Muscle tissue – contractile cells; allows movement of body parts
54
In which of the following situations do multiple organ systems work together to maintain homeostasis?
The respiratory and circulatory systems delivering oxygen to tissues
55
Which vertebrate organ system is correctly paired with one of its key functions?
Integumentary system – protects against infection and prevents water loss
56
A patient is suffering from dehydration. Which of the following feedback mechanisms is most likely to be triggered?
Negative feedback triggers the release of antidiuretic hormone (ADH) to retain water.
57
Which of the following scenarios is an example of a positive feedback loop?
Release of oxytocin to intensify contractions during childbirth
58
Why is negative feedback more common than positive feedback in maintaining homeostasis?
Most body functions require continuous adjustments to stay within narrow limits.
59
Which of the following best explains why muscle tissue is unique among the four main tissue types?
It is the only tissue type that can voluntarily generate force through contraction.
60
How does the nervous system help maintain homeostasis in response to a sudden drop in body temperature?
It signals the skeletal muscles to contract, generating heat through shivering.
61
Why is it necessary for healthy vegetarians to combine different plant foods or eat egg/milk products?
To provide all essential amino acids for protein synthesis
62
Small intestine
Chemically digests food and absorbs nutrients
63
What is the primary function of canine teeth?
Tearing and ripping food, particularly meat
64
During swallowing, how is food prevented from entering the trachea?
The epiglottis covers the trachea to direct food into the esophagus.
65
Which of the following best explains the structural adaptation of the digestive system in herbivores?
They have a longer digestive tract to allow more time for more digestion.
66
There is a sphincter at the lower end of our esophagus, This is known as the cardiac sphincter. A sphincter is a ring shaped muscle that is capable of tightening and relaxing. What can we assume its primary function to be?
Preventing acid reflex from the stomach into the esophagus.
67
Which of the following statements about the small intestine is true?
It contains villi and microvilli that increase surface area for nutrient absorption.
68
What is the primary function of the large intestine?
To absorb water and compact waste
69
What is the function of the lower esophageal sphincter?
It prevents food from re-entering the esophagus after reaching the stomach.
70
What is the primary difference between chemical and mechanical digestion?
Mechanical digestion physically breaks food down, while chemical digestion uses enzymes to break down macromolecules.
71
What is the function of the cilia in the trachea and bronchi?
To sweep mucus with trapped particles up and out of the respiratory tract
72
Which of the following correctly describes the three main phases of gas exchange in humans?
Breathing, gas transport in blood, exchange of gases with body cells
73
Which of the following is NOT a type of respiratory surface used by animals?
Nephridia
74
Why is breathing air easier than using water for gas exchange?
Air contains a higher concentration of oxygen than water.
75
What is the primary function of the tracheal system in insects?
To allow direct diffusion of oxygen from air to tissues
76
Which of the following best describes the function of alveoli in the mammalian respiratory system?
They increase surface area for gas exchange.
77
How does fetal hemoglobin differ from adult hemoglobin?
Fetal hemoglobin attracts oxygen more strongly than adult hemoglobin.
78
Which of the following is the correct path of airflow during inhalation in mammals?
Nasal cavity → trachea → bronchi → bronchioles → alveoli
79
Which of the following animals primarily relies on cutaneous respiration?
Worm
80
How does cutaneous respiration benefit amphibians in oxygen-poor environments?
It allows them to obtain oxygen even when water or air contains low concentrations of oxygen.
81
Which of the following initiates the process of blood clotting?
Damage to the lining of a blood vessel
82
What is the main difference between an open and closed circulatory system?
In a closed circulatory system, blood circulates through vessels; in an open system, blood directly bathes tissues.
83
In a fish’s cardiovascular system, blood flows in which of the following ways?
Blood circulates through a double-loop system, passing through the lungs and body tissues.
84
What is the difference between diastole and systole in the cardiac cycle?
Diastole is the relaxation phase of the heart, while systole is the contraction phase.
85
Which of the following blood vessels carries blood away from the heart?
Arteries
86
The structure of capillaries is ideal for gas and nutrient exchange because they:
Have thin walls, allowing for the easy exchange of gases and nutrients with tissues.
87
Which of the following is considered a normal blood pressure reading?
120/80
88
Which of the following is a characteristic of an open circulatory system?
Blood flows freely through body cavities, where it directly bathes tissues.
89
Which of the following is a general function of a circulatory system in all species?
To transport nutrients, gases, and wastes to and from cells
90
Which component of blood is primarily responsible for fighting infection?
White blood cells
91
Foreign molecules that elicit an immune response are called
Antigens
92
Which of the following best describes the role of innate immunity?
It provides a rapid, nonspecific defense against pathogens.
93
This type of immunity has a slower response, recognizes specific pathogens, and has memory.
Adaptive Immunity
94
Community protection and the reason behind state-mandated vaccinations is called
Herd Immunity
95
Which cells are primarily responsible for the specificity of the adaptive immune response? (destroy vs. memory)
B lymphocytes and T lymphocytes
96
What is the primary function of the lymphatic system?
To return excess interstitial fluid to the bloodstream and filter pathogens
97
Which organ is the primary site of T cell maturation?
Thymus
98
What is the main function of B lymphocytes in the immune response?
To produce antibodies that target specific antigens
99
What is the primary difference between a primary immune response and a secondary immune response?
The secondary response is stronger and faster due to memory cells.
100
What is the purpose of vaccination in relation to immune response?
To stimulate the primary immune response and create memory cells
101
Which of the following is NOT an adaptation for reducing the rate of heat loss to the environment?
Increasing blood flow to surface blood vessels
102
Which of the following is NOT one of the five major categories of adaptations for thermoregulation in animals?
Cellular respiration rate
103
Which osmoregulatory challenge do freshwater fish face?
Water tends to enter their bodies due to their hypotonic internal environment.
104
Which structure is responsible for the initial filtration of blood?
Glomerulus
105
Why is a dialysis machine necessary for some patients?
It compensates for kidney failure by filtering waste from the blood.
106
Which correctly matches a hormone to the gland from which it is produced and to its effect on target cells?
Thyroid hormone: anterior pituitary, regulates metabolism
107
How does the endocrine system primarily communicate signals throughout the body?
By releasing hormones into the bloodstream
108
Which endocrine gland is primarily responsible for regulating metabolism?
Thyroid gland
109
What are the three major types of sex hormones?
Androgens, estrogen, and progesterone
110
What is the main difference between how insulin and glucagon function?
Insulin lowers blood glucose levels, while glucagon raises them.
111
Monocot
A plant is observed to have parallel leaf venation, scattered vascular bundles in the stem, and fibrous roots.
112
Which tissue system would be most directly responsible for regulating gas exchange and protecting against water loss in leaves?
Dermal
113
Which of the following correctly matches plant growth with it's description?
Perennials: live and reproduce for many seasons
114
Which floral structure is responsible for producing pollen?
Anther
115
Which correctly matches the flower part with its function?
Ovary - houses ovules
116
Which of the following is primarily involved in transporting water upward from roots to leaves?
Xylem
117
What part of the flower typically becomes a fruit?
Ovary
118
What is a key function of the plant cell wall that distinguishes it from the animal cell membrane?
Provides structural support
119
What happens to the carbon dioxide taken up from the air by plant leaves?
It is converted into glucose during photosynthesis
120
What were the 3 main macronutrients that make up a plant?
Carbon, Oxygen, and Hydrogen
121
How does the intracellular route differ from the extracellular route when transporting materials?
It travels directly through cell walls
122
How do fertilizers help correct nutrient deficiencies in plants?
They provide essential nutrients like nitrogen, phosphorus, and potassium directly into the soil.
123
Which statement best compares organic and conventional agriculture?
Conventional farming typically uses chemical pesticides, while organic farming relies on natural methods.
124
A student observes that a plant’s leaves are turning yellow down the center of the leaf. This symptom most likely indicates a deficiency in:
Nitrogen
125
A farmer wants to grow crops without synthetic pesticides and fertilizers but is concerned about lower yield (amount of successful crops). What agricultural method is the farmer considering?
Organic agriculture
126
Why are carnivorous plants most commonly found in nutrient-poor soil?
They use insects to supplement essential nutrients, especially nitrogen.
127
Which of the following describes a mutualistic relationship between plants and bacteria?
The plant provides sugars to the bacteria in exchange for fixed nitrogen.
128
Which agricultural practice would most likely lead to nitrogen depletion in soil if not managed properly?
Repeatedly planting the same nitrogen demanding crop
129
Which plant response involves directional growth in response to physical touch, like vines wrapping around a support?
Thigmotropism
130
Which of the following best describes the general role of plant hormones in plant development?
They act as chemical messengers that regulate growth, development, and responses to stimuli.
131
Susy put a plant in her window. It keeps growing toward the light so she keeps spinning it around. Why is this happening?
Phototropism
132
A short day plant will flower
In the late fall / early winter when daylight is shorter
133
How do some plants defend themselves against herbivores?
By producing toxins or developing thorns
134
Adaptive advantage of innate behaviors.
(Behaviors that are "programmed," not learned) reliable, predictable, and efficient, ensuring basic survival and reproduction, especially in stable environments.
135
Habituation
A decrease in response to a repeated, harmless stimulus. Reduces unnecessary energy expenditure by ignoring redundant stimuli, freeing up resources for more important tasks. (A bird ignoring the repeated calls of other birds)
136
Sensitization
An increase in response to a stimulus, especially after a significant or threatening experience. Enhances the organism's sensitivity to potentially harmful stimuli, increasing the chances of survival. (A mouse exhibiting increased fear after being chased by a predator)
137
Classical Conditioning
Learning a new stimulus evokes a reflexive response by repeatedly pairing that stimulus with a stimulus that already evokes the response. Allows organisms to predict future events and prepare for them, such as learning to associate the sound of an alarm with the delivery of food. (Pavlov's dogs learning to salivate at the sound of a bell after being paired with food.)
138
Operant Conditioning
Learning through reinforcement or punishment, where a behavior is more or less likely to occur depending on the consequences that follow it. Allows organisms to learn which behaviors are most effective in achieving desired outcomes and to avoid those that are not. (A rat learning to press a lever for food (reinforcement) or avoid an area that delivers an electric shock (punishment).)
139
Imprinting
You are my mama. Ensures that young animals can recognize and follow their parents, aiding in survival and learning.
140
Observational Learning
Learning by watching the behavior of others. Allows organisms to quickly learn new skills or behaviors from more experienced individuals, especially when social structures are present. (A young chimpanzee learning to crack nuts by watching an older chimpanzee)
141
