Biology Exam Review Flashcards

A collection of 300 question-and-answer flashcards based on lecture notes for biology topics to aid in exam preparation.

What does the acronym Mrs. Gren stand for in characteristics of living organisms?

Movement, Respiration, Sensitivity, Growth, Reproduction, Excretion, Nutrition.

Define movement in living organisms.

An action by an organism or part of an organism causing a change of position or place.

What is respiration?

The chemical reaction that breaks down nutrient molecules in living cells to release energy for metabolism.

What are the two types of respiration?

Aerobic and anaerobic.

Where does aerobic respiration primarily take place?

In the mitochondria of cells.

What are the inputs and outputs of aerobic respiration?

Inputs: glucose and oxygen; Outputs: water, carbon dioxide, and energy.

What does sensitivity refer to in living organisms?

The ability to detect and respond to stimuli.

Differentiate between internal and external stimuli.

Internal stimuli are changes like pain or hunger, while external stimuli are changes in light or temperature.

Define growth in the context of living organisms.

The process by which an organism increases in size and mass, requiring energy.

What is the main purpose of reproduction in living organisms?

To produce more organisms of the same kind.

What is excretion?

The removal of toxic waste products from organisms.

List some excretory products.

Urine, sweat, and exhaled air.

What is nutrition in living organisms?

The intake of materials for energy, growth, and development.

Differentiate between autotrophic and heterotrophic organisms.

Autotrophic organisms can make their own food (like plants); heterotrophic organisms cannot (like animals).

What is the main objective of classification in biology?

To group organisms in an organized way based on their characteristics.

What is morphology?

The study of the form and structure of organisms.

What are the three types of classification methods?

Morphology, anatomy, and molecular classification (DNA/protein).

Describe the binomial nomenclature system.

A system for naming organisms using two parts: the genus name (capitalized) and the species name (lowercase), italicized or underlined.

Which organism represents the genus Homo?

Homo sapiens, which refers to humans.

What is the main characteristic that distinguishes vertebrates from invertebrates?

The presence of a vertebral column (backbone) in vertebrates.

What is the main characteristic of arthropods?

Segmented bodies and jointed limbs.

Name the four classes of vertebrates.

Fish, birds, mammals, reptiles, amphibians.

What is an important characteristic of all plant cells?

They contain chloroplasts and have a cell wall.

What is the role of chloroplasts in plant cells?

To conduct photosynthesis by capturing light energy.

Define diffusion.

The movement of particles from an area of high concentration to an area of low concentration.

What is osmosis?

The movement of water molecules across a semi-permeable membrane from a region of high water potential to a region of low water potential.

What happens to a red blood cell in a hypertonic solution?

The cell shrinks due to loss of water through osmosis.

What is active transport?

The movement of particles against their concentration gradient, requiring energy.

How do antibiotics work?

They specifically target bacteria without affecting human cells, often by breaking down cell walls.

What is the difference between DNA and RNA?

DNA contains deoxyribose sugar and is double-stranded, while RNA contains ribose sugar and is single-stranded.

What are enzymes?

Biological catalysts that speed up chemical reactions without being consumed in the process.

What factors affect enzyme activity?

Temperature, pH, enzyme concentration, and substrate concentration.

What is the role of the liver in metabolism?

It processes nutrients and detoxifies harmful substances.

What is photosynthesis?

The process by which plants convert light energy into chemical energy (glucose) using carbon dioxide and water.

What are the primary products of photosynthesis?

Glucose and oxygen.

Define biodiversity.

The variety of life in the world or a particular habitat or ecosystem.

What is a decomposer?

An organism that feeds on dead organic matter, recycling nutrients back into the ecosystem.

What is ecological succession?

The process by which ecosystems change and develop over time.

What are the main greenhouse gases?

Carbon dioxide, methane, nitrous oxide, and fluorinated gases.

What is the primary function of the circulatory system?

To transport oxygen, nutrients, hormones, and waste products throughout the body.

What is the distinction between arteries and veins?

Arteries carry oxygenated blood away from the heart; veins carry deoxygenated blood back to the heart.

What are the components of blood?

Red blood cells, white blood cells, platelets, and plasma.

Define immunity.

The ability of an organism to resist infection or disease.

What is a pathogen?

An organism that causes disease.

How do vaccines work?

They stimulate the immune system to recognize and fight pathogens without causing disease.

What is cancer?

A disease caused by uncontrolled cell division.

What is the role of the hypothalamus in maintaining homeostasis?

It controls body temperature, hunger, and thirst.

What does the endocrine system regulate?

Hormone levels and various biological processes.

What is selective breeding?

The process of breeding plants and animals for specific traits.

Define genetic engineering.

Direct manipulation of an organism's genes using biotechnology.

What is biodiversity and why is it important?

The variety of life on Earth, crucial for ecosystem stability and resilience.

What are some examples of biotic factors affecting ecosystems?

Predation, competition, and symbiotic relationships.

What are abiotic factors?

Non-living components of an ecosystem such as water, temperature, and soil.

What factors could limit a population's growth?

Availability of resources, predation, disease, and environmental conditions.

How does pollution affect ecosystems?

It can harm wildlife, decrease biodiversity, and disrupt natural processes.

What is conservation?

Efforts to preserve and protect natural resources and biodiversity.

What effects does deforestation have on the environment?

Loss of habitat, increased carbon dioxide levels, soil erosion, and disruption of water cycles.

What are the benefits of recycling?

Reduces waste in landfills, conserves resources, and lowers energy consumption.

Why is studying genetics important in biology?

It helps us understand heredity, genetic disorders, and evolution.

Describe the nitrogen cycle.

The process by which nitrogen is converted between its various chemical forms, critical for plant life.

What is a food web?

A system of interconnected food chains in an ecosystem.

How does energy flow through an ecosystem?

Starts from the sun, to producers, then to consumers, with energy lost at each level.

What is eutrophication?

The excessive richness of nutrients in a body of water, often due to runoff from land.

How can invasive species disrupt local ecosystems?

They can outcompete native species for resources, altering habitats and food webs.

What role do keystone species play in an ecosystem?

They have a disproportionately large effect on their environment relative to their abundance.

What is ecological balance?

The equilibrium between living organisms and their environment.

What are the consequences of global warming?

Climate change, rising sea levels, and extreme weather patterns.

How do hormones help maintain homeostasis?

By regulating physiological processes such as metabolism, growth, and mood changes.

Describe the role of the stomach in digestion.

It mechanically and chemically breaks down food using acids and enzymes.

What is the function of the small intestine?

It is the primary site for nutrient absorption from digested food.

Why is water important for living organisms?

It is essential for biochemical reactions, temperature regulation, and as a solvent.

What adaptations do plants have for survival in arid environments?

Deep roots, reduced leaf surface area, and water storage capabilities.

What is natural selection?

The process by which organisms better adapted to their environment tend to survive and produce more offspring.

Explain artificial selection.

Human-directed breeding to cultivate desired traits in organisms.

What is the relationship between biodiversity and ecosystem services?

Biodiversity enhances ecosystem productivity and resilience, providing crucial services for humanity.

How can biotechnology improve food production?

By enhancing crop yields and resistance to pests through genetic modification.

What is genetic mutation?

A change in the DNA sequence that can lead to new traits in an organism.

Define epigenetics.

The study of changes in organisms caused by modification of gene expression rather than alteration of the genetic code itself.

What are the main functions of proteins in living organisms?

Structural support, catalyzing reactions as enzymes, transport, and signaling.

How do biofuels contribute to renewable energy resources?

They are produced from organic materials, reducing reliance on fossil fuels.

In what ways can genetic engineering be used to address health issues?

By correcting genetic disorders, producing hormones, and creating vaccines.

Summarize the steps involved in the fermentation process.

Mix yeast with sugar and allow it to respire anaerobically to produce ethanol and carbon dioxide.

What are some reasons for the declining populations of certain species?

Habitat destruction, climate change, overexploitation, and introduction of invasive species.

What role does the pancreas play in digestion?

It produces digestive enzymes and hormones that regulate blood sugar levels.

What is selective pressure?

Environmental factors that influence which organisms survive and reproduce.

What are the stages of cellular respiration?

Glycolysis, the Krebs cycle, and oxidative phosphorylation.

How does temperature affect enzyme activity?

Increased temperature generally speeds up reactions but can denature enzymes if too high.

What is the importance of genetic diversity in a population?

It enhances resilience to diseases and environmental changes.

How might climate change impact marine ecosystems?

It can lead to ocean acidification, coral bleaching, and altered species distributions.

What type of data do scientists collect to monitor species populations?

Population size, distribution patterns, and habitat conditions.

Define the term 'carrying capacity'.

The maximum population size that an environment can sustain indefinitely.

Explain the concept of an ecological footprint.

The measure of human demand on Earth’s ecosystems, specifically the quantity of natural resources consumed.

What is sustainable agriculture?

Farming methods that maintain productivity while conserving resources and biodiversity.

Describe a biotic factor that can affect a habitat.

Factors such as presence and availability of food, predation, and competition among species.

What happens during decomposing?

Organic matter is broken down into simpler substances by microorganisms, returning nutrients to the ecosystem.

How does rainfall influence ecosystems?

Water availability affects plant growth, animal activity, and overall biodiversity.