Biology Exam One Study Guide

What is Science?

seeks to answer questions about the natural world

Scientific Method

Observations, Question, Hypothesis, Prediction, Test

What are some characteristics of living stimuli?

order, response to stimuli, growth, reproduction, inheritance of genetic information, regulation, homeostasis, acquire and use energy, and evolution.

Biotic Factors

fungi, bacteria, plants, artists, animals, and archea

Abiotic Factors

air, salinity, soil, temperature, light, water, minerals, pH, humidity

What is the cell theory?

cells are the basic building blocks of life; all living things or organisms are made of cells and their products; new cells arise from existing cells.

Parthenogenesis

new individual develops without fertilization

What is basic science?

answers questions about the natural world

What is applied science?

uses information gained to: create a product, treat a disease or condition, improve life, or fulfill some other practical need.

Viruses

have DNA or RNA and proteins but this genetic information and proteins vary.

How do viruses reproduce?

they bind to a host cell and its genome (DNA or RNA) enters, then the host cell copies viral genome and makes proteins, leading to a self-assembly into a new virus.

Prokaryotes

no nucleus

Eukaryotes

have a nucleus

What do all cells have?

a plasma membrane, cytoplasm, DNA, and ribosomes.

Domains

based on differences in the genetic structure of ribosomes.

What are the three domains?

Archea, Eucarya, and Bacteria

What domain are humans in?

Eucharya

Taxonomy

grouping of organisms by scientific means (features, DNA)

Levels of Organization in Biology

Cells

Organism

Populations

Communities

Ecosystems

Biosphere

Epidemic

an outbreak of disease that affects many in a population and begins to spread rapidly.

Pandemic

covers several countries or spreads from one continent to another; amount of people killed doesn’t matter as much as the rate of spread and how far it has spread.

Epidemiologists

study the spread of disease in human populations.

Communicable Disease

can get it from someone else.

Noncommunicable disease

is not spread from person to person

What was the first commercialized antibiotic and who discovered it?

Penicillin; Alexander Fleming

Antibiotics

chemicals produced naturally by microorganisms or synthetically, by humans that prohibits the growth of other microbes.

What is the main target of antibiotics?

to get the ribosome to stop protein production in bacterial cells; kill bacteria and fungi but not viruses.

Antimicrobial Resistance

viruses can become resistant to antiviral medications (Flu A, HIV)

Human Microbiome Project

identified microbial communities across the body

What does the human microbiome do?

processes food, processes waste, and improves the immune system.

Vagus (wandering) Nerve

communication pathway from your gut to your brain

Benefits of Breastfeeding

protects against childhood infections, reduces dental problems, improves survival rates, reduced risk for asthma, type 2 diabetes, and other disease

What percentage of a baby’s microbiome is from the milk and what percentage is from the mothers skin?

Milk: 30% Skin: 10%

What are some of the barriers of the human body that prevent infection?

skin when undamaged, physical and chemical barriers, acidic secretions of stomach, cilia, mucus, enzymes in tears and saliva, and the microbiome

Innate immune response

non-specific responses do not recognize invaders from previous attacks.

Macrophages

engulf and digest invading particles or organisms

Leukocytes

white blood cells

T-Cells

kill infected cells

B-Cells

produce antibodies against the pathogen so cells will not be infected; some B cells become memory cells (adaptive response)

Lymphatic System

antigens from lymph filtered through lymph nodes; antigens and antibody-complexed pathogens from blood filtered through the spleen (which is also lymph tissue)

Lymphoid Tissue

integrated into tissues of skin and intestines, bone marrow

How are vaccinations developed?

by using a dead organism, a mildly infectious pathogen, toxins from pathogen which have been inactivated, or through mRNA

How do vaccines work?

they stimulate an adaptive immune response

Autoimmune disease

a body amounts an immune response against its own tissues.

Plasma Membrane

surrounds each cell; regulates what goes in and out depending on cell type and role.

What do receptor molecules on the plasma membrane do?

they recognize a signal from outside the cell, transport that signal across the cell’s membrane and initiate the reading and response to that signal.

Evolution

a change in allele frequency in a population over time.

Allele

variation in a gene, such as blood type A or B

Natural Selection

a mechanism for evolution; preserves favorable variations.

What is the role of the nucleus?

it holds our DNA

Phenotype

physical expression of a trait: how you look, act, respond to stimuli (internal or external)

Adaptation

inherited trait (phenotype) that enhances survival in a particular enviornment.

What causes genetic variation in populations?

mutations in the DNA; change in one DNA base in a genotype can lead to a new phenotype; sexual reproduction can produce new combinations.