Science Final Exam

Plant Cell

The basic unit of life found in plants

Has a cell wall

Has a chloroplast

More rigid, cubic chape

Has a large central vacuole

Animal Cell

The basic unit of life found in humans and animals

Has no cell wall

No chloroplast

Less structured shape

Field of View

The area visible through the microscope eyepiece.

Magnification

The ability to make things look larger than they are (such as using a microscope lens)

Cell Theory

1. idea that all living things are composed of cells

2. cells are the basic units of life

3. new cells are produced from existing cells

Cell Wall

A rigid structure that surrounds the cell membrane and provides support to the cell

Cell Membrane

A semipermeable structure that controls which substances can enter or leave the cell.

Cytoplasm

A jellylike fluid inside the cell in which the organelles are suspended

Smooth Endoplasmic Reticulum (Smooth ER)

Where lipids are synthesized, calcium levels are regulated, and toxic substances are broken down.

Rough Endoplasmic Reticulum (Rough ER)

A membrane-enclosed cellular organelle with ribosomes attached to its outer surface; a site of synthesis for proteins.

Mitochondria

Powerhouse of the cell, organelle that is the site of ATP (energy) and CO2 production using glucose and O2.

Nucleus

A part of the cell containing DNA, produces RNA, and controls and regulates the activities of the cell.

Ribosome

Synthesizes proteins using ATP and RNA. Mostly found on the rough E.R. but can also be in the cytoplasm.

Vacuole

Cell organelle that stores materials such as water, salts, proteins, carbohydrates, and waste.

Vesicle

Small membrane-bound sac that functions in moving products into, out of, and within a cell.

Nucleolus

Found inside the nucleus and produces ribosomes.

Chloroplast

Organelle found in cells of plants that captures the energy from sunlight and converts it into chemical energy (photosynthesis.)

Golgi Apparatus

A system of membranes that modifies and packages proteins for export by the cell.

Lysosome

Cell organelle filled with enzymes needed to break down certain materials in the cell.

Prokaryotic Cell

A type of cell with no membrane-enclosed nucleus and membrane-enclosed organelles; found only in the domains Bacteria and Archaea.

Eukaryotic Cell

A type of cell with a membrane-enclosed nucleus and membrane-enclosed organelles. Examples of organisms with these cells are protists, plants, fungi, and animals.

Cell Cycle

Series of events in which a cell grows, prepares for division, and divides to form two daughter cells.

Interphase

Replicates its chromosomes, and prepares for cell division. Consists of G1, S, G2.

G1

The cell grows in preparation for DNA replication, and certain intracellular components, such as the centrosomes undergo replication. Essentially, it checks everything is ready before the cell replicates.

S

Synthesis. The phase of the cell cycle when DNA packaged into chromosomes is replicated.

G2

Similar to G1, a time for the cell to ensure that it is ready to proceed in the cell cycle and is the last stage for the cell to grow before dividing.

Prophase

First and longest phase of mitosis, during which DNA condenses into chromosomes and the centrioles separate and take up positions on the opposite sides of the nucleus

Metaphase

Second phase of mitosis, during which the chromosomes line up across the center of the cell.

Anaphase

The third phase of mitosis, during which the chromosome pairs separate and move toward opposite poles.

Telophase

The final phase of cell division, in which the chromatids or chromosomes move to opposite ends of the cell and two nuclei are formed.

Cytokinesis

The final phase of a cell cycle resulting in the division of the cytoplasm.

Centrioles

A minute cylindrical organelle near the nucleus in animal cells, occurring in pairs and involved in the development of spindle fibres in cell division.

Chromatids

A thread like strand made up of DNA. Two chromatids joined together with a centromere make a chromosome.

Chromosomes

Two chromatids connected together with a centromere that contain DNA. These chromosomes split apart during cell division to even split the DNA into two daughter cells.

Organ System

A group of organs that work together to perform a specific function.

Connective Tissue

A body tissue that provides support for the body and connects all of its parts (e.g. tendons that connect muscle and bones.)

Nervous Tissue

A body tissue that carries electrical messages back and forth between the brain and every other part of the body.

Epithelial Tissue

A body tissue that covers the surfaces of the body, inside and out.

Muscle Tissue

A body tissue that contracts or shortens, making body parts move.

Esophagus

A muscular tube that connects the mouth to the stomach.

Small Intestine

Digestive organ where most chemical digestion and absorption of food takes place. It is divided into three parts: duodenum (breaks down food), jejunum, and ileum (both absorb nutrients from food).

Large Intestine

The portion of the digestive tube that encircles the abdomen around the small bowel, consisting of the cecum, the colon, and the rectum. It helps regulate water balance and eliminate solid waste.

Stomach

Large muscular sac that continues the mechanical and chemical digestion of food.

Rectum

A short tube at the end of the large intestine where waste material is compressed into a solid form before being eliminated through the anus.

Liver

Produces bile, which carries away waste and break down fats in the small intestine during digestion.

Gall Bladder

An organ that stores bile and releases it as needed into the small intestine.

Pancreas

Produces enzymes which break down sugars, fats, and starches, and hormones that regulate blood sugar levels.

Ventilation

Movement of air in and out of the lungs; breathing.

External Respiration

The exchange of gases with the external environment, and occurs in the alveoli of the lungs.

Internal Respiration

The exchange of gases with the internal environment, and occurs in the tissues.

Gas Exchange

The process of obtaining oxygen from the environment and releasing carbon dioxide.

Alveoli

Where the lungs and the blood exchange oxygen and carbon dioxide during the process of breathing in and breathing out.

Bronchus

One of the two tubes that connect the lungs with the trachea.

Bronchioles

Airways in the lungs that lead from the bronchi to the alveoli.

Larynx

Voice box; passageway for air moving from pharynx to trachea; contains vocal cords.

Capillaries

Tiny blood vessels that connect arteries and veins. Allows oxygen and nutrients to pass from the blood to the tissues, and waste products to pass from the tissues to the blood.

Pulmonary Artery

Carries deoxygentated blood from the heart to the lungs.

Pulmonary Vein

Carries oxygenated blood from the lungs to the heart.

Inferior Vena Cava

Carries blood from lower regions of the body to right atrium.

Superior Vena Cava

Receives blood from the head and arms and chest (upper body) and empties into the right atrium of the heart.

Diffusion

The process by which molecules move from an area of higher concentration to an area of lower concentration.

Cancer Cells

Divide excessively and can invade other tissues and displace normal cells. Cannot form specialized cells as it divides too quickly. Has a larger nucleus due to excessive amounts of DNA.

Red Blood Cells

Blood cells that carry oxygen from the lungs to the body cells.

White Blood Cells

Blood cells that perform the function of destroying disease-causing microorganisms.

Plasma

Takes nutrients, hormones, and proteins to the parts of the body that need it.

Platelets

Tiny blood cells that help your body form clots to stop bleeding.

Digestive System

Breaks down food into absorbable units that enter the blood for distribution to body cells.

Photosynthesis

Process by which plants and some other organisms use light energy to convert water and carbon dioxide into oxygen and high-energy carbohydrates such as sugars and starches

Light

Electromagnetic radiation. Light is both a particle and a wave. When it is a particle, it is known as a photon, a massless packet of energy. When it is a wave, it is known as a stream of photons travelling in a wave-like pattern.

Visible Light

Electromagnetic radiation that can be seen by humans. Everything else cannot be seen without the use of special equipment.

Natural Sources of Light

Light created without human involvement:

- Sun

- Stars

- Fire

- Lava

- Bioluminescence

Artificial Sources of Light

Light created with human involvement:

- Flashlight

- Lightbulbs

- Device screens

Electromagnetic Spectrum (EM)

The range of all types of electromagnetic (EM) radiation or wavelengths.

Long wavelengths have low energy and low frequency (easy to remember as all the terms start with "L")

Short wavelengths have high energy and high frequency. (Think of me or Martin when you read one of these terms. We're short, but we have loads of energy and therefore frequency)

Wave Model of Light

A way of explaining the behavior of light; involves picturing it travelling as a wave.

Crest

The highest point of a wave.

Trough

The lowest point of a wave.

Rest Position

The position where the wave is at rest, halfway between the crest and trough.

Amplitude

Height of a wave (distance from the equilibrium to a crest or trough.)

Wavelength

Distance between two crests or two troughs.

Labelled as the greek symbol lambda: λ

Formula: λ = c / f

c or v is speed (note: c is used to refer to the speed of light in a vacuum, while v is for all other mediums)

f is frequency

Oscillation

The act of a wave moving up and down / cycle between up and down.

Period

How long it takes for a wave to return to the same state, e.g. the time between two crests or troughs.

Do not confuse with frequency, which is # of cycles per 1 second, whereas period is # of seconds per 1 cycle.

Labelled as capital "T"

Formula: T = 1/f (f is frequency)

Measured in seconds.

Frequency

The number of complete wavelengths that pass a point in a given time. Wavelength and Frequency are inversely proportional to each other.

Shorter/Skinny Wavelengths = Higher Frequency

Longer/Wider Wavelengths = Low Frequency

Think of it as short wavelengths being skinny, which allows more of them to fit inside a given time. Long wavelengths are wide, which means less can fit inside a given time.

Measured in hertz (Hz)

Labelled as lowercase "f"

Formulas:

f = 1/T

f = c/λ

Energy

Directly proportional to frequency.

High Frequency = High Energy

Low Frequency = Low Energy

Speed

The distance a wave travels over time. Labelled as "c" when referring to the speed of light in a vacuum, and "v" when referring to the speed of light in other mediums (forms of matter, water, diamond, etc.) There are two formulas to calculate it:

c = f (frequency) * λ (wavelength)

c = distance / time

If given T (period), it can be used as time in the second formula or be converted into f (frequency) in the first formula.

Speed of Light

How fast light travels in a vacuum: 3.00 x 10^8 m/s

Light will move slower in water and other mediums.

Important Formulas

Speed (c):

c = f * λ

c = distance / time

Frequency (f):

f = 1/T

f = c / λ

Period (T):

T = 1/f

Wavelength (λ):

λ = c / f

Additive Colour Theory

Theory of light stating all visible colours are made by combining three primary colours, red, blue, and green. This is because the cones in our retina can only detect these 3 colours.

Bioluminescence

The production of light by means of a chemical reaction in an organism.

Incandescent Light

Light generated by heating a piece of metal until it glows.

Fluorescent Light

Light generated by exciting mercury vapour via an electric current, which creates UV light. This UV light causes a phosphor coating inside the light bulb to produce visible light.

Phosphor

A solid material that can emit light by fluorescence.

Phosphorescence

Light emitted by storing energy from a light source and then slowly remitting it over a long period of time. Commonly seen in glow-in-the-dark objects.

Chemiluminescence

The direct production of light as the result of a chemical reaction with little or no heat produced. All forms of bioluminescence are special kinds of chemiluminescence.

Light Emitting Diode (LED)

Light produced as a result of an electric current flowing through semiconductors. Semiconductors are materials that can change how well they conduct electricity.

The process of converting electrical energy into light energy is called electroluminescence.

White Light

Mixture of all the colors in the visible spectrum.

Prism

A piece of glass that separates white light into colours of the spectrum.

Transparent

A material or substance that allows light to pass through.

Translucent

A material or substance that allows some light to pass through.

Opaque

A material or substance that allows no light to pass through.

Reflection

The bouncing back of a wave when it hits a surface through which it cannot pass.