BioSci - Prelims

Skepticism

A researcher publishes a study claiming that a newly developed herbal preparation improves memory. Another researcher does not immediately accept the claim despite the impressive results. She examines the methodology, sample size, controls, and statistical analysis before deciding whether the conclusion is justified.

Which scientific attitude is MOST evident?

Formulating a hypothesis

A Psychology student notices that a particular plant species growing near a laboratory window consistently develops larger leaves than plants of the same species kept farther from the window. Instead of immediately concluding that sunlight causes larger leaves, the student proposes a testable explanation and plans an experiment.

Which step of the scientific method is the student primarily demonstrating?

Willingness to change position

A scientist has supported a particular explanation for a biological phenomenon for several years. However, newly obtained experimental evidence consistently contradicts the explanation. Rather than defending the original position, the scientist modifies the explanation to accommodate the new evidence.

Which scientific attitude is BEST demonstrated?

No, because science cannot answer questions of morality.

A psychologist is investigating whether a particular intervention reduces anxiety. After collecting experimental data, a student asks, “Can science determine whether helping anxious individuals is morally right or morally wrong?”

Based on the limitations of science presented in the lecture, which is the BEST response?

Homeostasis

During a hot afternoon, a person's body temperature begins to rise. Physiological mechanisms are activated to counteract the change and restore the internal condition toward its normal state.

Which characteristic of life is MOST directly illustrated?

Regulation

A plant absorbs water through its roots and transports it throughout its body. Meanwhile, the plant releases water vapor through its leaves. The coordinated control of these processes allows the organism to maintain proper internal functioning.

Which characteristic of life is MOST directly represented?

Energy processing

A researcher examines a human specimen and observes that individual cells are organized into tissues, tissues form organs, and organs work together as organ systems.

Which characteristic of life is being demonstrated?

The plant demonstrates response to stimuli.

A student accidentally touches the leaves of a Mimosa plant. Within seconds, the leaves fold inward. The student concludes that the plant is capable of detecting and responding to a change in its environment.

Which conclusion is MOST appropriate?

Energy processing

A green plant uses sunlight to produce organic molecules, while organisms within the same ecosystem obtain energy by consuming plants or other organisms.

Which characteristic of life is MOST directly represented?

Molecular biology and ecology

A scientist investigates how DNA is organized, expressed, and replicated within cells. Another scientist studies how organisms interact with one another and with their environment.

Which pairing correctly identifies the biological fields involved?

Social sciences

A researcher investigates how human behavior is influenced by relationships, social structures, and interactions within communities.

Based on the classification of science presented in the lecture, this investigation belongs primarily to:

Inquiry and evidence

A student claims that a certain biological phenomenon occurs because “it was simply meant to happen.” When asked for evidence, the student cannot provide observations, experiments, or a testable explanation.

Which feature of science is MOST clearly missing from the student's explanation?

Spontaneous Generation Theory

A student claims that flies originate directly from decaying meat because flies frequently appear around decomposing material. Another student argues that the observation alone does not demonstrate that the meat itself produces flies.

The first student's claim most closely reflects which historical theory?

Chemical Evolution Theory

A researcher proposes that early Earth contained simple chemicals that gradually assembled into increasingly complex molecular systems, eventually contributing to the emergence of life.

Which theory of life is MOST consistent with this explanation?

Interplanetary Theory

Scientists propose that certain materials associated with the origin of life may have been transported from extraterrestrial environments. A student argues that the origin of life should therefore be considered in relation to substances or particles originating beyond Earth.

Which theory is most closely associated with this perspective?

Natural selection

A population of insects contains individuals with naturally occurring differences in coloration. Birds more frequently consume insects that are easily seen against the environment. Over many generations, the less-visible coloration becomes more common in the population.

Which Darwinian principle BEST explains this observation?

A—Lamarck; B—Darwin

Two biologists explain why giraffes have long necks:

• Biologist A: Giraffes repeatedly stretched their necks to reach food, causing their necks to become longer during their lifetimes. These acquired changes were then passed to their offspring.

• Biologist B: Giraffes naturally varied in neck length, and individuals whose necks provided an advantage were more likely to survive and reproduce.

Which interpretation correctly identifies the two explanations?

Needs, use and disuse, and inheritance of acquired traits

A population of organisms encounters a major environmental change. According to Lamarck's concept presented in the lecture, organisms respond to environmental changes by altering their behavior, and physical changes acquired during their lifetime may subsequently be transmitted to offspring.

Which Lamarckian concepts are MOST directly involved?

Hugo de Vries — Mutation Theory

A population of flowering plants suddenly exhibits a new inherited characteristic that was not previously observed in the population. A researcher proposes that the appearance of new varieties or species may result from mutations.

Which scientist and theory are MOST closely associated with this explanation?

Observation, scientific method, empiricism, and willingness to change position

A researcher observes that students who regularly sleep for at least seven hours appear to perform better on examinations. She proposes a possible explanation, designs a study, collects data, analyzes the results, and reports her findings. Later, another study produces evidence that challenges part of her original conclusion. She revises her explanation rather than rejecting the new evidence.

Which combination of scientific principles is MOST strongly demonstrated?

SCIENCE

"It is a pursuit and application of knowledge and

understanding of the natural and social world

following a systematic methodology based on

evidence."

SCIENCE

OBSERVATION, IDENTIFICATION, DESCRIPTION,

EXPERIMENTAL INVESTIGATION

SCIENCE

"an approach to understanding the natural world that is

based on inquiry - a search for information, evidence,

explanations, and answers to specific questions."

SCIENCE

"Branch of knowledge or study dealing with a body

of facts or truths systematically arranged and

showing the operation of general laws."

SCIENCE

KNOWLEDGE. KNOWING.

EXPERTNESS, OR EXPERIENCE

SCIENCE

is about knowing the physical and natural world."

Scientific method

is a process used to solve certain problems

and explain phenomena

Scientific method

The process of observing, asking questions, seeking for

answers through series of experiments or tests, and analyze it.

Applied in all SCIENCES.

These procedures form a powerful tool for understanding

nature.

make an observation, ask a question, test hypothesis and gather data, examine test results and form a conclusion

steps of the scientific method

Problems have solutions

Scientists believe that problems can be investigated and potentially solved through systematic observation, research, and evidence.

Respect for power of theoretical structure

Scientists recognize that theories are useful frameworks for organizing facts and explaining relationships between things.

Thirst for knowledge

Scientists have a strong curiosity and desire to learn. They continuously ask questions and seek new information.

Ability to separate fundamental concepts from irrelevant

Scientists know how to identify the important information and ignore details that don't contribute to the question being studied.

Ability to suspend judgment

Scientists avoid making conclusions too quickly. They wait until there is enough evidence.

Appreciation of probability and statistics

Scientists understand that research results are often about likelihoods and patterns, rather than absolute certainty.

Automatic preference for scientific explanation

When explaining something, scientists prefer explanations based on evidence, testing, and scientific principles rather than superstition or unsupported beliefs.

Understanding the tolerance limits

Scientists understand that measurements and conclusions have limits. Results may not apply perfectly to every person or situation.

Awareness of assumptions

Scientists recognize that they often make assumptions and need to consider whether those assumptions are actually valid.

Determinism

is the idea that events have causes. Scientists assume that behavior and events can be explained by identifiable factors rather than happening completely randomly.

Empathy for human conditions

Scientists recognize that research involves real people with feelings, experiences, and limitations. Researchers should understand and respect participants' experiences.

Empiricism

means relying on observation and evidence obtained through experience or experimentation.

Loyalty to reality

Scientists prioritize what the evidence shows, even when the result doesn't match what they expected or wanted.

Parsimony

means choosing the simplest adequate explanation when multiple explanations can account for the same observation. Easy keyword: Simplest explanation

Precision

Scientists try to be exact and specific when describing concepts, procedures, and results.

Respect for scientific paradigms

Scientists recognize existing scientific models, theories, and established ways of understanding a subject. They use them as foundations for new research while remaining open to improvement.

Scientific manipulation

This doesn't mean manipulating people. It means systematically changing or controlling variables to determine whether one thing causes another.

Skepticism

Scientists question claims instead of automatically believing them. They ask, “What evidence supports this?”

Willingness to change position

Scientists must be willing to change their beliefs or conclusions when new evidence contradicts them.

Answer questions about value

Answer questions of morality

Deal with unique

Answer the questions about

Supernatural

Science cannot:

Social sciences

Deals with human behavior and its

relationship within societies

Formal/Abstract sciences

Focuses on the abstract structured described by

formal system

Natural sciences

Seek to understand the governing rules

of the natural world

BIOLOGY

Field of study that deals with living organisms and

their vital processes.

Genetics, Molecular biology, Ecology, Microbiology, Zoology,

Physiology, and botany

Different fields of biology

Order

Living organisms have an organized structure. Their bodies are arranged in an orderly way, from smaller parts to larger and more complex systems.

Response to Stimuli

Living things can detect and respond to changes in their environment. These changes are called stimuli.

Reproduction

Living organisms can produce new organisms of the same species.

Growth and Development

Living organisms grow and change throughout their life.

Regulation

Living organisms have mechanisms that control and coordinate their internal processes and activities

Homeostasis

the ability of an organism to maintain a stable internal environment, even when the external environment changes. Easy keyword: Internal balance

Energy Processing

Living organisms need energy to survive and perform life processes, such as moving, growing, repairing cells, and reproducing.

Divine Creation Theory

This theory states that life was created by a supernatural or divine being.

Cozomozoic or Interplanetary Theory

This theory suggests that life, or the basic ingredients needed for life, came to Earth from outer space.

Abiogenesis or Spontaneous Generation Theory

Spontaneous generation was the old belief that living organisms could suddenly arise from nonliving matter.

Chemical Evolution Theory

This theory proposes that the first forms of life developed gradually from nonliving chemicals on early Earth.

Lamarck's Theory

proposed that organisms change because of use and disuse and that characteristics acquired during an organism's lifetime could be passed to its offspring.

Lamarck's Theory

Giraffes stretched their necks to reach leaves → their necks became longer → they passed this acquired characteristic to their offspring.

Darwin's Theory

For example, giraffes with naturally longer necks may have been better able to reach food. If they survived and reproduced more successfully, longer-neck traits could become more common.

Darwin's Theory

proposed evolution through natural selection.

Mutation theory

associated with Hugo de Vries, proposed that mutations—sudden changes in genetic material—can produce new characteristics and contribute to evolution.

Matter

anything that occupies space and has mass. is composed of chemical elements.

Mass

amount of material in an object

Human

made up of matter.

25

____ elements are essential in

humans

96%, 4%, 0.1%

____ of human body -

oxygen (O),hydrogen (H),

nitrogen (N), and carbon (C).

____ - seven elements

Calcium

____ trace elements

Iodine defiency

can lead to goiter

ELEMENTS

can combine to form COMPOUNDS

atom

smallest unit of matter

one

Every ELEMENT is made up of ___ kind of ATOM

Protons

- positive (+) electrical charge

Electron

negative (-) electrical charge

Neutron

electrically neutral (no charge)

COMPOUND

is a substance formed by two or

more different types of ELEMENTS

IONIC BOND

transferring of electrons

COVALENT BOND

Sharing of electrons between two (2) or more atoms. Strongest bonds

ionic and covalent

TWO TYPES OF CHEMICAL BONDS

HYDROGEN BONDS

special type of dipole-dipole bond

HYDROGEN BONDS

hydrogen atom bonded to strongly electronegative atom

Organic compounds

contain carbon, usually bonded to hydrogen

Inorganic compounds

usually don’t contain carbon

Carbohydrates, Lipids, Protein, Nucleic Acids

Large Biological molecules

Carbohydrates

Often referred as "carbs"

class of molecules that includes sugars and polymers of sugars

Primary source of energy (animals); building material (plants)

MONOSACCHARIDES, DISACCHARIDES, POLYSACCHARIDES

Different classes of carbohydrates

MONOSACCHARIDES

Greek word: mono- single and sacchar- sugar = Simple sugars

Monomers (building blocks) - they cannot be broken down into

smaller sugars. Example: glucose, galactose, Fructose

Glucose

blood sugar

Dextrose

example of glucose, given as an IV to sick or injured

patients

provides an immediate energy

source to tissues in need of

repair.

Fructose

fruit sugar

ISOMERS

Molecules that have the same

molecular formula but different

structures.

Galactose

(brain sugar)

DISACCHARIDES

double sugar (two monosaccharides

through dehydration reaction)

two monosaccharides form a covalent bond

and lose a water molecules in the process. Example: Lactose, Maltose, Sucrose