Honors Bio Midterms

Hypothesis

A educated guess that explains an observation or phenomenon that you can then test through study and experimentation.

Control group

The group in an experiment that does not receive the variable you are testing, used as a benchmark for other groups.

Experimental group

The group that receives the variable being tested in an experiment.

Independent variable

A variable that is changed to test its affect on another variable. (cause)

Dependent variable

The factor being measured or observed in an experiment, the outcome/effect.

Experimental constants

Any factor kept the same throughout an experiment.

How many variables should you change at a time in a good experiment? Why?

Only one. Adding more variables causes confusion on which variable caused which result.

Quantitative data

Data that can be measured numerically.

Qualitative data

Non-numerical data describing characteristics, attributes, etc.

What are the levels of organization in a living thing, starting with a cell?

Cells, tissues, organs, organ systems, organism

What are the 8 characteristics of living things?

Reproduction, heredity, cellular organization, growth and development, response to stimuli, adaptation through evolution, homeostasis, and metabolism

What element makes a compound organic?

Carbon.

What are the most common elements of living things?

CHNOPS (carbon, hydrogen, nitrogen, oxygen, phosphorus, sulfur

What are the 4 types of macromolecules?

Lipids, carbohydrates, nucleic acids, proteins

What is the monomer of a carbohydrate?

Monosacharrides.

What’s the purpose of eating carbohydrates?

Short-term energy.

What are the monomers of a lipid?

Glycerol + fatty acids, long-term energy.

What is the purpose of a lipid?

Moving + storing energy, insulation, hormone creation

What is the monomer of a protein?

Amino acids

What is the purpose of a protein?

Building + repairing tissue, main building block for bones, muscles, etc.

What are enzymes?

Biological catalysts that speed up chemical reactions.

What do enzymes do for a reaction?

Lowers the activation energy needed for the reaction to start, speeding it up.

What affects how well an enzyme works?

Temperature, pH, substrate concentration, enzyme concentration

What is the monomer of nucleic acids?

Nucleotide

What is the purpose of nucleic acids?

Stores, transfers, and expresses genetic information

What’s the difference between RNA and DNA?

DNA replicates and stores genetic information, while RNA converts the genetic information contained within DNA to a format used to build proteins, and then moves it to ribosomal protein factories. DNA is double helixed and RNA is single helixed.

What is the main function of the nucleus/what do they do?

Acts as the cells control central, storing the cell’s genetic material and directing all cell activities.

What is the main function of the mitochondria/what do they do?

Powerhouse of the cell, generates ATP.

What is the main function of the chloroplasts/what do they do?

Photosynthesis, absorbing light energy.

What is the main function of the cell wall/what does it do?

Provides structural support, shape, and protection to plant cells.

What is the main function of the cell membrane/what does it do?

Regulates the transport of materials exiting and entering the cell.

What are cell membranes made of?

A phospholipid bilayer.

What is diffusion?

Passive movement of molecules to an area of lower concentration.

What is facilitated diffusion?

The process of passive transport of molecules/ions across a membrane using transport proteins because the molecules are too large or polar to pass through themselves.

What is active transport?

The movement of molecules/ions across a cell membrane from areas of lower concentration to higher concentration.

What is osmosis?

The movement of water from a higher concentration level to a lower concentration level across a semipermeable membrane.

What does isotonic mean?

A solution with the same concentration of solutes and water,

What does hypotonic mean?

A solution with a lower concentration of solutes and a higher concentration of water.

What does hypertonic mean?

A solution with a higher concentration of solutes and a lower concentration of water.

What is endocytosis?

How cells “eat” or “drink” by engulfing sustances from outside, like nutrients, fluids, or bacteria, into the cell using the cell membrane, which folds inward and pinches off to form a vesicle that carries the material inside.

What is exocytosis?

The process where a cell expels large molecules or waste by enclosing them in a membrane-bound sac (vesicle), which then moves to the cell's outer membrane, fuses with it, and releases the contents outside the cell

What are autotrophs?

Organisms that make their own food and energy.

What are heterotrophs?

Organisms that can’t make their own food and must get energy from eating other living things.

What is the formula for photosynthesis?

6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂

What organisms go through photosynthesis?

Plants, algae, and some bacteria

What’s the main purpose of photosynthesis?

To convert light energy into chemical energy stored in glucose.

What is water’s purpose in photosynthesis?

Provides electrons + hydrogen ions, source of the oxygen released as a byproduct when water molecules are split. Water is the main source of power (electrons, protons) to drive the energy conversion needed to make glucose.

What is the difference between the light dependent and light independent reactions?

The goal of the light-dependent reactions of photosynthesis is to collect energy from the sun and break down water molecules to produce ATP and NADPH. These two energy-storing molecules are then used in the light-independent reactions. The goal of the light-independent reactions (Calvin cycle) is to assemble a molecule of glucose. This is the part of photosynthesis that requires the CO₂ the plant gets from the air.

What’s the formula for cellular respiration?

C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O + Energy (ATP)

What organisms go through cell respiration?

All living organisms.

What’s the main purpose of cell respiration?

To convert the chemical energy in food into a useable source of energy (ATP).

How does photosynthesis relate to cell respiration?

Photosynthesis makes the glucose that is used in cellular respiration to make ATP. The glucose is then turned back into carbon dioxide, which is used in photosynthesis. While water is broken down to form oxygen during photosynthesis, in cellular respiration oxygen is combined with hydrogen to form water. (opposite and complementary process)

What is the path of digestion?

A series of organs made to move food throughout your body and absorb any useful nutrients from it.

List the organs in order of the path of digestion.

Mouth, pharynx, esophagus, stomach, small intestine, large intestine, rectum

Mouth

Chews and breaks down food when it enters the digestive system, using a mix of saliva and other enzymes

Pharynx

A passageway for air to enter the larynx + lungs and food + liquid to enter the esophagus.

Esophagus

Serves as a “tunnel” from the mouth to the stomach.

Stomach

Breaks down food through physical churning and chemical digestion, produces acid and enzymes to help digest food.

Small intestine

Finishes digesting food, absorbs essential nutrients.

Large intestine

Turns food waste into stool, absorbs water + electrolytes, producing and absorbing vitamins.

Anus

Expels waste out of the body.

What gasses do you inhale?

Oxygen, nitrogen + mix of other gasses

What gasses do you exhale?

CO2 and water vapor.

Arteries

Transports oxygen-rich blood from the heart to the rest of the body.

Veins

Transports deoxygenated blood, waste, and CO2 from the body’s tissues back to the heart and lungs for reoxygenation.

Capillaries

Connects arteries and veins to deliver oxygen and nutrients to cells.

Liver

Filters blood, detoxifies harmful substances, produces proteins/chemicals, and fights off infections. (mainly)

Pancreas

Releases enzymes to help with digestion and to regulate blood sugar.

List each level of the tropic pyramid in order.

Producers, primary consumers, secondary consumers, tertiary consumers

How much energy does each level of the trophic pyramid get?

10%

List the energy in each trophic level if the autograph starts with 5000 calories of energy.

5000, 500, 50, 5

What does “CHNOPS” stand for?

Carbon, hydrogen, nitrogen, oxygen, phosphorus, sulfur

List the carbon cycle.

Photosynthesis, cell respiration, consumption, decomposition, fossilization, combustion