Biology Unit 1A Terms for Test

Cell

The first characteristic of living things/life: To be made up of cells.

Definition: A basic unit of structure and the function of living things (the smallest unit considered alive).

Unicellular

Definition: Only one cell (single-celled).

Examples: Bacteria and amoeba (protists). Protists are anything that is not an animal, plant, or fungus.

Multicellular

Definition: More than one cell.

Examples: Animal, plants, and fungi.

Stem Cell

Definition: Has the potential to become any specific cell type. Everything multicellular starts as stem cells and then become different as a result of undergoing differentiation.

Differentiation/Cell Specialization

Definition: Stem cells are each programmed to perform specific jobs and become different. Ex. cells’ jobs could be forming tissue, carrying oxygen, etc.

Prokaryotic

Definition: Before the development of a nucleus- lack a nucleus.

Eukaryotic

Definition: Contains a nucleus.

Examples: Protists (amoeba), Fungi, Animals, Plants

Metabolism

Definition: The sum of all chemical reactions in an organism. This is a mechanism for obtaining/the utilization of energy.

Second Characteristic of Living Things: Obtain and use materials/energy. The materials used are called nutrients used for energy/structure. These nutrients come from the surrounding environment.

Autotroph

Definition: Capable of synthesizing (the ability to build a complex compound by combining simpler molecules) its own food source. They utilize small chemicals in the environment along with an energy source to make their own food.

Types:

• Photoautotroph- organisms convert solar energy into chemical energy (sugar).

• Chemoautotroph- synthesizes chemicals to produce energy.

Heterotroph

Definition: Must obtain food from an outside source. Heterotrophs use cellular respiration to turn food into usable cellular energy called ATP.

Cellular Respiration

Third Life Process (How Living Things Maintain Life): Nutrients do not contain energy in a form compatible with life. The energy in nutrients (calories) must be converted to a form that is compatible (Adenosine Tri Phosphate- ATP). This occurs within the mitochondria (powerhouse) of each cell.

Simple Definition: How we obtain energy from the food we eat.

Scientific Definition: The process by which all living things break down the chemicals of food to release the energy required for cellular work.

Aerobic Respiration

Definition: Requires oxygen.

Anaerobic Respiration

Definition: Can take place in the absence of oxygen.

Response

Third Characteristic of Living Things: Response to stimuli within the environment.

Definition: Organism detect and respond to environmental stimuli.

Stimulus

Definition: A signal to which an organism responds. It could be visual, olfactory (smell), auditory, or sensory.

Homeostasis

Fourth Characteristic of Living Things: Maintain a stable internal environment.

Definition: A stable internal environment in spite of unstable external environment.

Negative Feedback

Definition: When the body responds to a change by reversing it to bring conditions back to homeostasis and normalcy.

Examples: When body temperature rises, we sweat more, causing our temperature drop.

Positive Feedback

Definition: When the body responds to a change by increasing/strengthening it to cause the change to continue until a specific event is completed.

Examples: Childbirth. When a baby’s head pushes against the cervix, it stretches, triggering the release of oxytocin. Oxytocin causes the uterus to contract strongly, and the release of oxytocin and the subsequent contractions increase in strength until the baby is born. Then, the mother’s body returns to homeostasis.

Develop- TO FINISH

Fifth Characteristic of Living Things: Growth and development.

Definition: Every organism has a pattern of growth and development. Growth is represented by an increase in cells whereas development…

DNA

Sixth Characteristic of Living Things: Universal genetic code.

Definition: All organisms store genetic information in DNA, which is copied and passed to offspring.

Central Dogma: All living things read the same genetic code the same way.

Examples: Liger and tigons (tigers and lions read DNA the same way).

Reproduction

Seventh Characteristic of Living Things: Reproduction is essential for life and survival.

Asexual Reproduction

Definition: A single organism produces an identical clone.

S*xual Reproduction

Definition: Cells from two parents unit to form a new organism. This creates genetic diversity.

Evolution

Eighth Characteristic of Living Things: All living things evolve.

Definition: Genetic change of time (generations). Started from Charles Darwin’s Natural Selection theory (aka Survival of the Fittest)- organisms with traits that help them survive and reproduce are more likely to pass those traits down to their offspring.

Archae

“Ancient bacteria”

Cell Type: Prokaryotic (lacks a nucleus and organelles)

Number of Cells: Unicellular

Cell Wall? Yes but lack petidoglycans

Mode of Nutrition: Both autotrophic and heterotrophic

They are hyperthermophiles (love environments with heat), halophiles (love salty environments), and acidophiles/basophiles (acidic environments).

Eubacteria

Today’s Bacteria

Cell Type: Prokaryotic (lacks a nucleus and organelles)

Number of Cells: Unicellular

Cell Wall? Yes, and cell walls are made up of peptidoglycans (interweaving pieces of protein and sugar)

Mode of Nutrition: Both autotrophic and heterotrophic

Protista

Cell Type: Eukaryotic

Number of Cells: Unicellular (but is colonial and forms colonies)

Cell Wall? Some do have cell walls.

Mode of Nutrition: Both autotrophic and heterotrophic.

Examples: Amoeba, Euglena, Paramecium

Fungi

Cell Type: Eukaryotic

Number of Cells: Most are multicellular (except mold)

Cell Wall? Yes, and cell walls are made up of chitin

Mode of Nutrition: Heterotroph

These are called decomposers, or detritivores!

Plants

Cell Type: Eukaryotic

Number of Cells: Multicellular

Cell Wall? Yes, and cell walls are made up of cellulose

Mode of Nutrition: Autotrophs

Animals

Cell Type: Eukaryotic

Number of Cells: Multicellular

Cell Wall? None!

Mode of Nutrition: Autotroph

Nutrition

First Life Process (How Living Things Maintain Life): All living things must obtain materials and energy, and this is how that is done.

Definition: Nutrients are a substance from the environment that provides nourishment essential for growth and maintenance of life. Organisms obtain these nutrients through a metabolic strategy.

Ingestion: Internalizing those nutrients.

Digestion: Mechanical and chemical processes that break down complex food molecules into simpler nutrients they can digest.

Trophic Energy Pyramid: Shows flow of nutrients and energy through levels of the ecosystem (each level corresponds to a pyramid step). Primary producers (algae) are at the base. Then, there’s primary consumers (herbivores), secondary consumers (carnivores like fish and sea stars), tertiary consumers (octopi), and top predators (tiger sharks). There is less available energy every step of the pyramid (hence why there are so little sharks in our ecosystems).

Transport

Second Life Process (How Living Things Maintain Life).

Definition: The process where nutrients are carried from one location to another.

Examples: The circulatory system moves substances throughout the body using blood (ex. transports oxygen from the lungs to the body cells). Transport also occurs across the cell membrane.

Diffusion

Definition: Movement of particles from a high concentration area to a low concentration area to ensure particles are evenly spread out/equally distributed. Diffusion does not require energy!

Examples: Oxygen moves from blood (high concentration area) into body cells (low concentration area). The oxygen spreads into cells via diffusion.

Synthesis- TO FINISH

Fourth Life Process (How Living Things Maintain Life).

Definition: We utilize the energy from cellular respiration to make other compounds necessary for life by combining simple substances chemically to form more complex substances.

Examples: Protein synthesis- joining together Amino Acids to make large…

Growth

Fifth Life Process (How Living Things Maintain Life).

Definition: The process by which living organisms increase in size by increasing their number of cells. New cells are made from nutrients from the food we eat like proteins, carbs, vitamins, and minerals. Cells start as stem cells, but after undergoing cellular specialization or differentiation, they become tissues.

Excretion

Sixth Life Process (How Living Things Maintain Life).

Definition: The removal of waste from the organism’s body. Generally, as humans, we excrete carbon dioxide. Additionally, our sweat excretes the same chemicals as urine does.

Regulation

Seventh Life Process (How Living Things Maintain Life).

Definition: All the activities that help to maintain an organism’s homeostasis or help an organism respond to stimuli within their environment. Regulation requires the coordination of multiple body systems.

Hormones

Definition: The body’s chemical messengers (hormones tell different parts of your body what to do). The endocrine system is responsible for producing and releasing these hormones into your bloodstream. The endocrine system is helping regulate your body by sending chemical messages through hormones.

Example: When your blood sugar gets too high, your pancreas releases insulin. Insulin signals your body’s cells to take glucose from your blood, which lowers blood sugar.

Stress/Fight or Flight Response

Stressor

Chronic vs. Immediate Stress

Immediate/Short-Term: Very intense and real, short in duration, and there is an immediate recovery back to set point (Homeostasis).

Chronic/Long-Term: Less intense, long in duration, and leads to an elevated resting cortisol and a frequent struggle in your body to return itself back to its set point of Homeostasis.

Cortisol

Definition: A stress hormone that keeps you in Fight or Flight. Once the stressor is eliminated/the stress ends, your body gradually reduces its cortisol to return to Homeostasis.

Sympathetic Nerves

Definition: The Sympathetic Nervous System is in charge of activating your body’s Fight or Flight response when you are stressed. Your pupils dilate (to let more light in), your heartbeat increases (allowing more blood flow), your breathing rate increases (to allow more oxygen) and digestion and other “unnecessary” functions are inhibited which allows you to conserve energy for the danger. Cortisol, the stress hormone, is keeping all of this going. Your body’s response to stress is amplified which is a positive feedback mechanism.

Norepinephrine and Epinephrine (Adrenaline)

Definition: Epinephrine is a hormone that prepares for Fight or Flight by increasing heart rate and breathing rate, while Norepinephrine is a hormone that increases alertness and blood pressure (they both help you prepare for danger).

Parasympathetic Nerves

Definition: The Parasympathetic Nervous System is in charge of returning your body back to Homeostasis. Your pupils constrict, your heartbeat slows, and the activity of your stomach is stimulated again. Your body rests and digests to bring itself back to its set point of Homeostasis.

Reproduction

Eighth Life Process (How Living Things Maintain Life)

Metabolism

Ninth Life Process (How Living Things Maintain Life)

Definition: All of the chemical reactions occurring within the cells of an organism. It is the balance of catabolic and exergonic reactions. Catabolic reactions break down complex molecules into simpler ones, and exergonic reactions release energy.

Atomic/Chemical Level

First Level of the Hierarchy/Organization of Living Things

Definition: Atoms are the basic unit of all matter.

Examples: Carbon, Hydrogen, Oxygen, and Nitrogen.

Molecules

Second Level of the Hierarchy/Organization of Living Things

Definition: Atoms combine through chemical bonding to form molecules that are essential to life such as water (H20), 02, carbs, lipids (all for energy), proteins (for structure), and nucleic acids (for information).

Organelles (Tiny Organs)

Third Level of the Hierarchy/Organization of Living Things

Definition: Structures within a cell that carry out cellular function, life functions, and processes. The mitochondria is in charge of cellular respiration and the chloroplast is in charge of photosynthesis.

Cellular Level

Fourth Level of the Hierarchy/Organization of Living Things

Definition: The chemicals of life interact to form life at the cellular level. This level concerns interactions of organelles. Cells are the basic unit of structure and function of living things, and the two cell types are prokaryotic and eukaryotic.

Tissue

Fifth Level of the Hierarchy/Organization of Living Things

Definition: A group of cells acting together to perform the same function (AFTER the stem cells undergo differentiation and specialization).

Organ

Sixth Level of the Hierarchy/Organization of Living Things

Definition: A group of tissues acting together for a common purpose.

Organ System

Seventh Level of the Hierarchy/Organization of Living Things

Definition: A group of organs performing the same tasks. The Circulatory System is in charge of transport and the Cardiovascular System brings oxygen in and carbon dioxide out. Other examples of systems are the Nervous System, Reproductive System, the Skeletor Muscular, the Endocrine System, the Excretory/Digestive System, the Immune System, and the Integumentary System.

Organism

Eighth Level of the Hierarchy/Organization of Living Things

Definition: A group of systems that work together or any individual living thing. There are multicellular organisms.

Population

Ninth Level of the Hierarchy/Organization of Living Things

Definition: A group of similar organisms (species) living in a specific geographic area which are interdependent. They are connected through competition and reproduction. Organisms of a similar morphology can reproduce fertile offspring (so, ligers wouldn’t be able to have kids).

Community

Tenth Level of the Hierarchy/Organization of Living Things

Definition: The interaction of a group of populations (different species) that are all living.

Ecosystem

Eleventh Level of the Hierarchy/Organization of Living Things

Definition: The interaction of all of the biotic (living) and abiotic (non-living) factors within a certain geographic range. There is an important exchange and flow of nutrients and energy between the factors that maintains the ecosystem.

Biotic

Definition: Biological influences on organisms- essentially, any living part of the environment (animals, plants, mushrooms, bacteria, etc).

Abiotic

Definition: Any non-living part of the environment.

Examples: Sunlight, heat, precipitation, humidity, wind, soil, weather, geology, etc.

Biome

Twelfth Level of the Hierarchy/Organization of Living Things

Definition: The interaction of closely related ecosystems. The first interaction is climate, which is long-term weather patterns. The second interaction is types of flora, which is vegetation in an area. There is also an interaction between fauna or animals, who, based on need can migrate to different biomes.

Examples: Tundra, coniferous forest, temperate deciduous forest, desert, grassland, rainforest, and shrublands.

Biosphere

Definition: Interaction of all biotic and abiotic factors on the planet, interacting on a global scale.