13 - Chemistry and Biology Flashcards
This deck explores fundamental concepts in chemistry and biology, including atomic structure, chemical reactions, cellular biology, and genetics. The goal is to provide a comprehensive understanding of biological processes and their significance in the diversity of life. (152 cards)
1
Q
Define:
element
A
- Type of matter with specific chemical and physical properties.
- Cannot be broken down into other substances.
Atoms are the individual units of each element. For example, hydrogen (H) and oxygen (O) are elements, while water (H2O) is not.
2
Q
Explain:
What characteristic identifies an atom as a specific element?
A
The number of protons, known as the atomic number.
Example: Carbon has an atomic number of 6.
3
Q
Identify:
3 main subatomic particles that make up an atom.
A
- Protons
- Electrons
- Neutrons
These particles define the structure and properties of an atom.
Protons and neutrons are found in the nucleus, while electrons are in the electron cloud.
4
Q
Define:
proton
A
Positively charged subatomic particle with a mass of approximately 1 amu.
Protons are found in the nucleus of an atom.
5
Q
Define:
atom
A
The smallest unit of matter that retains the properties of an element.
Atoms are composed of subatomic particles and cannot be broken down into other substances.
6
Q
Define:
atomic mass unit
(amu)
A
Standard unit of mass used for measuring particles as small as subatomic particles.
7
Q
Define:
atomic number
A
It is the number of protons in an atom. It defines the atom as a specific element.
8
Q
Describe:
What happens when an atom gains or loses electrons?
A
It becomes an ion; losing electrons creates a cation and gaining electrons creates an anion.
Ions carry a charge due to the imbalance of protons and electrons.
9
Q
Define:
neutrons
A
Neutral subatomic particles located in the nucleus with protons.
They have a mass of about 1 amu.
10
Q
Describe:
How is the atomic mass of an atom calculated?
A
It is equal to the number of protons plus the number of neutrons.
Electrons contribute negligibly to the atomic mass.
11
Q
Define:
isotopes
A
Atoms with a different number of neutrons than the average number for that element.
Isotopes can be stable or unstable, with the latter undergoing radioactive decay.
12
Q
Define:
periodic table
A
A chart organizing all elements by their physical and chemical properties based on atomic number.
Each element is represented by its atomic number, chemical symbol, abbreviation and atomic mass.
13
Q
Explain:
How are atoms created?
A
Through nuclear fission or nuclear fusion.
Fission splits larger atoms, while fusion combines smaller atoms.
14
Q
Describe:
The nucleus of an atom.
A
The dense center of an atom containing protons and neutrons.
Most of the mass of an element is found in the nucleus.
15
Q
Explain:
The difference between metals and non-metals.
A
- Metals are typically solid, good conductors and shiny.
- Non-metals can be solid or gas, are poor conductors and are dull.
Most elements are metals.
16
Q
Define:
halogens
A
Highly reactive non-metals found in Group 7 of the Periodic Table.
They include fluorine, chlorine, bromine, iodine, and astatine.
17
Q
Identify:
What defines the properties of an element?
A
The number of subatomic particles it contains.
Protons, neutrons and electrons determine unique characteristics.
18
Q
Describe:
molecule
A
It is composed of at least two atoms joined by a chemical bond.
Atoms of elements build different molecules.
19
Q
Define:
compound
A
A group of molecules.
For example, water is a compound, a group of individual H2O molecules.
20
Q
Explain:
How do elemental personalities affect their bonding?
A
Elements can be shy or social; shy elements prefer to be alone, while social elements bond with others.
21
Q
List:
The two types of chemical bonds.
A
- Ionic
- Covalent
22
Q
Identify:
The difference between a pure substance and a mixture.
A
- A pure substance is made up of only one compound or element.
- A mixture has two or more compounds/elements that do not form chemical bonds.
23
Q
Explain:
How can you determine if a bond is ionic?
A
If it conducts electricity when dissolved in pure water.
24
Q
Explain:
What happens to the components in a mixture?
A
They keep their own chemical identities.
25
# Identify:
4 key properties of a **mixture**.
1. No chemical force between constituent particles.
1. Ratio of components is not well-defined.
1. Properties are similar to its constituents.
1. Can be separated by normal physical methods.
## Footnote
Methods of separation include **distillation**, **filtration** and **boiling**.
26
# Identify:
4 factors that affect the **boiling point** of a **mixture**.
1. Pressure
1. Molecular nature
1. Molecular weight
1. Impurities
## Footnote
As pressure decreases, boiling point decreases; higher molecular weight generally increases boiling point.
27
# Identify:
The main characteristic of **covalent bonds**.
**Electrons are shared** by the constituent atoms in the molecule.
28
# Identify:
2 types of **mixtures** based on **particle distribution**.
1. Homogeneous mixture
1. Heterogeneous mixture
## Footnote
Homogeneous mixtures have **even distribution**, while heterogeneous mixtures have **uneven distribution**.
29
# Identify:
4 characteristics of **homogeneous mixtures**.
1. Uniform composition
1. Particles not visible to the naked eye
1. Identical phase throughout
1. No line of separation between components
## Footnote
An example is a sugar solution in water.
30
# Identify:
4 characteristics of **heterogeneous mixtures**.
1. Non-uniform composition
1. Particles visible to the naked eye
1. Different phases present
1. Line of separation between components
## Footnote
An example is a mixture of sand and water.
31
# Identify:
2 categories of **properties of matter**.
1. Physical properties
1. Chemical properties
32
# Define:
**physical properties**
Properties that describe matter through **visual inspection** or **measurement**.
33
# Identify:
What are some **properties** of matter?
* Length
* Volume
* Mass
* Color
* Texture
* Shape
* Density
34
# Identify:
The **phase changes** considered **physical** changes.
* Melting
* Freezing
* Vaporization
* Condensation
* Sublimation
35
# Explain:
What defines the **chemical properties** of matter?
How matter **interacts** with other substances during a **chemical process**.
36
# Identify:
Examples of **chemical properties**.
* Reactivity
* pH
* Corrosion
* Conductivity
37
# Describe:
color
| Context: properties of matter
**Physical property** observed as the portion of the visible spectrum reflected.
38
# Describe:
pH
Determined by the **concentration of H+ ions** released when dissolved in water.
## Footnote
The pH scale range is **0 to 14** and classifies substances as **acidic**, **basic** or **neutral**.
39
# Identify:
How is **density** calculated?
By dividing **mass** by **volume**.
## Footnote
Density refers to how much **mass** of a substance is packed into a given **volume**.
40
# Define:
reactivity
The ability of matter to **interact** with another substance to **create something new**.
41
# Define:
corrosion
The **reaction of oxygen with metal**, altering its structure.
42
# List:
The five types of **chemical reactions**.
* Combination reactions
* Decomposition reactions
* Single-replacement reactions
* Double-replacement reactions
* Combustion reactions
43
# Define:
reactants
**Substance(s) that go into a chemical reaction**, typically found to the left of the arrow in a reaction formula.
## Footnote
They are transformed into **products** during the reaction.
44
# Explain:
**Products** in a chemical reaction
**Substance(s) formed as a result of a chemical reaction**, typically found to the right of the arrow in a reaction formula.
## Footnote
They differ chemically from the original reactants.
45
# Identify:
The **pH** value that indicates a **neutral substance**.
7
## Footnote
Neutral substances have equal amounts of hydrogen (H⁺) and hydroxide (OH⁻) ions.
46
# List:
The properties of **acids**.
* pH less than 7
* Turns litmus paper red
* Tastes sour
* Feels wet
* Proton donors
* Release H+ (hydrogen ions)
## Footnote
Common examples include vinegar and citrus fruits.
47
# List:
The properties of **bases**.
* pH greater than 7
* Turns litmus paper blue
* Tastes bitter
* Feels slippery
* Proton acceptors
* Release OH- (hydroxide ions)
## Footnote
Common examples include ammonia and detergents. All **alkaline** substances are bases, but not all bases are alkaline (since some bases do not dissolve in water).
48
# Define:
A neutralization reaction
The reaction of acids and bases **to form water and salt**.
## Footnote
This process results in a pH of 7 (pure water).
49
# Explain:
The role of **pH indicators**.
They determine whether a substance is an **acid** or **base** using **color changes**.
## Footnote
Examples include **litmus paper** and **phenolphthalein**.
50
# Define:
buffers
Solutions that **resist changes in pH**, composed of a weak acid and a weak base.
## Footnote
Buffers are crucial for maintaining optimal pH in biological processes.
51
# Identify:
The most important **neutral substance**.
Water
## Footnote
Water flushes out toxins and promotes healthy cellular functions.
52
# Identify
What can alter the **pH** of a person's body?
* Exercise
* Certain foods
## Footnote
Fluctuations can affect enzyme functioning.
53
# Define:
**Solubility** in chemistry
The maximum amount of solute that gets **dissolved** in a given quantity of a solvent at a specific temperature.
## Footnote
Solubility explains the nature and the rate at which a solute dissolves in a solvent.
54
# List:
The three most common **forms of matter**.
* Solid
* Liquid
* Gas
## Footnote
Matter has physical properties such as **odor**, **shape**, **melting point** and **solubility**.
55
# Identify:
The **difference** between a *solute* and a *solvent*.
* A **solute** is a substance that **dissolves in a solvent**.
* A **solvent** is the **liquid in which the solute dissolves**.
## Footnote
Water is the most commonly used solvent in chemistry.
56
# Define:
An aqueous solution
A solution in which the **solvent is water**.
## Footnote
Aqueous solutions are formed when a **solute** is dissolved in water.
57
# Define:
precipitate
A **solid** that forms when an insoluble solute is mixed with a liquid or solvent.
## Footnote
A precipitate remains suspended or floating in the liquid.
58
# Explain:
What defines a **saturated solution**?
A solution that **contains the maximum amount of solute** and cannot dissolve more.
## Footnote
Saturated solutions are in equilibrium with undissolved solute.
59
# Identify:
The **units** used to express **solubility**.
* Milligrams per liter (mg/L)
* Grams per 100 milliliters of solvent (g/100ml)
## Footnote
These units help describe how much solute can dissolve in a solvent.
60
# Explain:
What happens to the **solubility of gases** with increasing **temperature**?
It decreases.
## Footnote
**Gas molecules** regain energy and **escape** from the solvent as temperature rises.
61
# Describe:
A solubility curve
A **graph** drawn to determine the **solubility of solutes** at different **temperatures**.
## Footnote
It visually represents how solubility changes with temperature.
62
# Identify:
3 factors affecting **solubility**.
* Temperature
* Pressure
* Nature of interaction
## Footnote
These factors influence how well a solute dissolves in a solvent.
63
# Identify:
The basic **unit** of life.
Cell
## Footnote
All living beings are made up of one or more cells, which are the structural and functional units of life.
64
# Define:
eukaryotic
Refers to organisms composed of one or more cells containing a **nucleus** and other membrane-bound **organelles**.
## Footnote
Animal cells have membrane-covered **organelles**, a **nucleus**, and **mitochondria**.
65
# Define:
organelles
Structures or parts within the cell.
## Footnote
They are responsible for specific functions such as **protein synthesis**, **cellular respiration**, **packaging and secretion of proteins**.
66
# Identify:
The function of the **nucleus** in an **animal cell**.
It is the **control center** of the cell.
## Footnote
The nucleus contains **DNA** and regulates most cell activities, including metabolism, growth and reproduction.
67
# Describe:
The function of **lysosomes**.
**Digesting** and **recycling** toxic substances and waste.
## Footnote
Lysosomes are **organelles** that handle waste management in the cell.
68
# Identify:
The **organelle** responsible for **cellular aerobic respiration**.
Mitochondria
## Footnote
**Mitochondria** convert oxygen and nutrients into energy.
69
# Describe:
An adaptive trait.
Any **genetic characteristic** that helps a plant or animal **increase its chances of reproducing**.
70
# Identify:
The role of **ribosomes** in a cell.
Protein synthesis.
## Footnote
Ribosomes help synthesize proteins needed by the cell and are often referred to as **protein factories**.
71
# Identify:
The main component of the **plasma membrane**.
Phospholipid bilayer.
## Footnote
It is a **selectitvely permeable** membrane that separates the **cytoplasm** from cell **organelles**.
72
# Explain:
The role of the **nucleus** in a cell.
It controls and regulates **cellular activities**, including **growth** and **mitosis**, and contains the **cell's DNA**.
73
# Define:
Mitosis
A process where one cell **divides** or **replicates** to form two **daughter cells**.
## Footnote
This process copies cell's **DNA** (deoxyribonucleic acid), which holds the instructions for its functions.
74
# Describe:
**Cytoplasm** and its functions.
* It is a **jelly-like fluid** filling the cell.
* It helps cells maintain their **shape** (this is called **turgidity**) and suspends **organelles**.
* Contains **molecules** and **enzymes** for breaking down waste and supporting **metabolism**, including **glycolysis**.
* The **cytosol**, a part of the cytoplasm, supports cell **shape** but does not contain **organelles**.
## Footnote
It is the site of most cellular activities.
75
# Fill in the blank:
The \_\_\_\_\_\_\_\_ helps package and secrete **proteins**.
Golgi apparatus
## Footnote
The Golgi apparatus receives proteins from the endoplasmic reticulum.
76
# List:
The two types of **endoplasmic reticulum**.
* Rough ER
* Smooth ER
## Footnote
Rough ER has ribosomes and helps with protein synthesis, while Smooth ER synthesizes lipids and detoxifies.
77
# List:
The two major **phases** of the **cell cycle**.
* Interphase
* Cell division (also called M phase)
78
# Define:
Interphase
A growth, DNA synthesis and preparatory phase before mitotic division.
## Footnote
**Interphase** can take up to 95% of the cell cycle time.
79
# List:
The four stages of **mitosis**.
* Prophase
* Metaphase
* Anaphase
* Telophase
## Footnote
**Cytokinesis** occurs during the latter half of telophase.
80
# Explain:
What happens during **prophase**?
**Sorting** and **organization** occur; the **mitotic spindle** forms.
## Footnote
The **nuclear envelope** dissolves to allow **microtubule proteins** to attach to **sister chromatids**.
81
# Describe:
What occurs during **metaphase**?
**Sister chromatids** align along the **metaphase plate**.
## Footnote
This alignment is facilitated by **microtubule proteins** from the **mitotic spindle**.
82
# Explain:
What happens during **anaphase**?
**Sister chromatids** are pulled apart as **individual chromosomes**.
## Footnote
The cell begins to stretch out during this phase.
83
# Explain:
What occurs during **telophase**?
Individual **chromosomes** are pulled towards opposite ends, and a new **nuclear envelope** forms.
## Footnote
The cell prepares to split during **cytokinesis**.
84
# Fill in the blank:
**DNA** is replicated during the \_\_\_\_\_\_\_ of the **cell cycle**.
S phase
## Footnote
DNA replication does not occur during any other part of interphase or M phase.
85
# Define:
Cytokinesis
The process that **splits** one cell into two identical daughter cells.
## Footnote
It occurs at the end of telophase.
86
# Define:
Cellular respiration
The **metabolic process** by which living cells acquire chemical energy from food.
## Footnote
It involves **biochemical reactions** that break chemical bonds within food molecules, such as **glucose**.
87
Where does **cellular respiration** primarily take place in **eukaryotic cells**?
In the mitochondria.
## Footnote
This organelle is crucial for cellular energy production.
88
# List:
The two types of **cellular respiration**.
* Aerobic respiration
* Anaerobic respiration
## Footnote
Aerobic respiration requires oxygen, while anaerobic respiration occurs without oxygen.
89
# Define:
fermentation
A process that may follow **glycolysis** in **anaerobic organisms**. It produces small amounts of **ATP** and results in byproducts like **lactic acid** or **ethanol**.
90
# Define:
Photosynthesis
The process by which plants use **light energy** from the sun to convert **carbon dioxide** and **water** into **sugar**, with **oxygen** as a by-product.
## Footnote
The prefix '**photo**' means **light** and '**synthesis**' means **to put together**.
91
# List:
The reactants of **photosynthesis**.
* Water
* Carbon dioxide
* Sunlight
## Footnote
**Reactants** are the raw materials necessary for the chemical reaction to take place.
92
# List:
The products of **photosynthesis**.
* Glucose
* Oxygen
## Footnote
These are the **substances** produced by the **chemical reaction** during **photosynthesis**.
93
# Explain:
The role of **chlorophyll** in **photosynthesis**.
It absorbs **light energy**, which is necessary for the process of **photosynthesis**.
## Footnote
Chlorophyll is the green pigment found in the chloroplasts of plant cells.
94
# Explain:
The significance of **glucose** produced in **photosynthesis**.
It serves as **food** for the plant and stores **chemical energy** for later use.
## Footnote
Glucose must be broken down by cellular respiration to release its energy.
95
# Define:
An autotroph
An organism that can make its own food.
## Footnote
Plants are a primary example of **autotrophs**, but some **protists** and **bacteria** also perform **photosynthesis**.
96
# Define:
A heterotroph
An organism that must find food to survive.
## Footnote
Unlike autotrophs, heterotrophs cannot produce their own food.
97
# List:
The three core **food groups** in a balanced meal.
* Proteins
* Carbohydrates
* Lipids
98
# List:
The four major classes of **biological macromolecules**.
* Carbohydrates
* Lipids
* Proteins
* Nucleic acids
## Footnote
These macromolecules are essential for the survival and growth of living organisms.
99
# List:
The **elements** that make up **proteins**.
* **C**arbon
* **H**ydrogen
* **O**xygen
* **N**itrogen
| (CHON)
## Footnote
Proteins may also contain **sulfur** and **selenium**.
100
# List:
The two major types of **carbohydrates**.
* Simple carbohydrates
* Complex carbohydrates
## Footnote
**Simple carbohydrates** include **monosaccharides** and **disaccharides**; **complex carbohydrates** include **polysaccharides**.
101
# Identify:
The primary function of **carbohydrates**.
Primary source of **energy** for all cells.
## Footnote
They are also involved in energy storage and assisting in lipid metabolism.
102
# List:
The **elements** that **lipids** mainly consist of.
* **C**arbon
* **H**ydrogen
* **O**xygen
| (CHO)
## Footnote
Lipids contain fewer polar hydroxyl groups than carbohydrates.
103
# List:
The functions of **lipids**.
* Help **build** cell membranes, **store** energy and **send signals**.
* Help regulate body **temperature**.
* Aid in **absorbing** fat-soluble nutrients.
* As visceral fat, they **protect** organs like the heart, kidneys, and liver.
104
# Identify:
The function of **nucleic acids**.
Transmission of genetic information and protein synthesis.
## Footnote
Nucleic acids include **DNA** and **RNA**.
105
# List:
The two main types of **nucleic acids**.
* DNA (deoxyribonucleic acid)
* RNA (ribonucleic acid)
## Footnote
Both are composed of **nucleotides**.
106
# Define:
Genetics
The study of **genes** and **DNA**.
## Footnote
Genetics has expanded to include gene regulation, expression and applications in human diseases.
107
Who is considered the father of **genetics**?
Gregor Mendel
## Footnote
Mendel studied **inheritance of traits in pea plants** in the 1800s.
108
# Define:
heredity
The **passing of traits** from one generation to the next.
109
# Define:
inherited traits
Traits that can be passed down through generations because they are coded for in **DNA**.
## Footnote
Inherited traits are also known as **heritable traits**.
110
# List:
Examples of **inherited traits**.
* Hair color
* Skin color
* Height
* Coat or feather color
* Ability to resist disease or pests
* Differences in protein function
111
# Explain:
Natural selection
The process by which organisms better fit for their environment **survive** and **reproduce**.
## Footnote
This concept was studied by **Charles Darwin**. It favors individuals with advantageous traits in a given environment.
112
# Define:
chromosomes
Linear segments of **DNA** that contain many **genes**.
113
# Explain:
The **difference** between *diploid* and *haploid*.
* **Diploid** refers to having **two copies** of each chromosome.
* **Haploid** refers to having **one copy** of each chromosome.
114
# Define:
A gene
A **section of DNA** that codes for a particular protein.
115
# Define:
alleles
Different versions of a same **gene**, but have different **genetic variations** at a particular **locus**.
116
# Identify:
The **difference** between *dominant* and *recessive alleles*.
Dominant alleles cover up the effect of recessive alleles.
117
# Define:
A genotype
The **specific combinations of alleles** an organism inherits for a particular gene.
118
# Define:
An organism
Any living thing.
## Footnote
This includes everything from microscopic bacteria to large mammals like the blue whale.
119
# List:
The key **characteristics** shared by all living **organisms**.
* Order
* Nutrition
* Response to stimuli
* Reproduction
* Growth and development
* Homeostasis
## Footnote
These characteristics define what it means to be a living organism.
120
# Define:
homeostasis
The ability of an organism to maintain constant internal conditions.
## Footnote
Maintaining homeostasis allows organisms to **function optimally**.
121
# Explain:
What **evidence** exists for the earliest known **organisms**?
Microbes preserved in stromatolites, dating back **3.5 billion years ago**.
## Footnote
Stromatolites are layered, hard mounds formed by photosynthetic **cyanobacteria**.
122
# List:
The two main types of **reproduction** in organisms?
* Asexual reproduction
* Sexual reproduction
## Footnote
**Asexual** reproduction involves **one parent**, while **sexual reproduction** involves **two parents**.
123
# Define:
Taxonomy
The scientific study of **naming**, **defining** and **classifying organisms** based on shared characteristics.
## Footnote
Taxonomy helps scientists categorize the vast diversity of life.
124
Who developed the original system of **classification for organisms**?
Carolus Linnaeus in 1758.
## Footnote
His system utilized **seven taxonomic categories**.
125
# List:
**Linnaeus**'s original taxonomic classification system.
* **D**omain (Introduced by Carl Woese in 1981)
* **K**ingdom (Most general, 6 kingdoms)
* **P**hylum
* **C**lass
* **O**rder
* **F**amily
* **G**enus
* **S**pecies (Most specific, ~30 million species)
## Footnote
"**D**ear **K**ing **P**hilip **C**ame **O**ver **F**or **G**ood **S**oup" is a clever memory aid.
126
# List:
Three **ways to describe** the millions of **organisms** on Earth.
* Unicelluar vs multicellular
* Prokaryotes vs eukaryotes
* Feeding style
127
# Define:
Unicellular organisms
They consist of a **single cell** that performs all the functions of the **organism**.
128
# Define:
Multicellular organisms
They are composed of **multiple cells**, each contributing to the proper functioning of the **organism**.
129
# Define:
Prokaryotes
**Unicellular organisms** that lack membrane-bound structures, including a nucleus.
## Footnote
Examples include **bacteria** and **archaea**.
130
# Define:
Eukaryotes
Organisms that have cells with a **nucleus** and **membrane-bound organelles**.
## Footnote
Examples include animals, plants and fungi.
131
# List:
The **feeding styles** of organisms.
* Producers
* Consumers
* Herbivores
* Carnivores
* Omnivores
* Scavengers
* Decomposers
## Footnote
These categories define how organisms obtain their energy from food sources.
132
# Define:
Human anatomy
The **study** of the structures of the **human body**.
## Footnote
It involves collecting data about larger structures like organs and body systems.
133
# List:
The major organs of the human body.
* Heart
* Brain
* Stomach
* Kidneys
* Lungs
## Footnote
These organs are **essential for survival**; problems with them can be life-threatening.
134
# Identify:
What **cells** form when they group together?
Tissues
135
# List:
The major human **body systems**.
* Integumentary System
* Immune System
* Digestive System
* Excretory System
* Nervous System
* Endocrine System
* Circulatory System
* Respiratory System
* Skeletal System
* Muscular System
* Reproductive System
## Footnote
These systems work together to perform **essential functions for survival**.
136
# Describe:
The function of the **circulatory system**.
To transport fluid throughout the body, providing cells with oxygen and nutrients, and removing waste products.
## Footnote
It includes the heart, blood vessels, and blood.
137
# List:
The main components of the **respiratory system**.
* Lungs
* Nose
* Pharynx
* Trachea
* Diaphragm
## Footnote
The respiratory system **supplies** blood with **oxygen** and **removes carbon dioxide**.
138
# Identify:
The primary role of the **digestive system**.
To break down food.
## Footnote
It includes organs like the mouth, esophagus, stomach and intestines.
139
# Fill in the blank:
The \_\_\_\_\_\_\_ system is responsible for removing waste from the body.
excretory
## Footnote
It includes the kidneys, bladder, ureters and urethra.
140
# Describe:
What does the **nervous system** control?
All other organ systems.
## Footnote
It comprises the brain, spinal cord, sensory organs and nerves. **Stimuli** travel as electrical impulses through nerves to the brain, which sends instructions back to the body on **how to react**.
141
# Describe:
The function of **hormones** in the **endocrine system**.
To **regulate processes** such as growth, reproduction and energy production.
## Footnote
**Hormones** are **chemical messengers** that work with the nervous system.
142
# Identify:
The largest **organ** of the body.
Skin
## Footnote
The **integumentary system**, which includes skin, protects internal organs.
143
# Define:
Immune system
**The defense system of the body**, made up of **lymphatic vessels**, responsible for screening the blood for **pathogens**.
## Footnote
It also includes **white blood cells** that patrol the body checking for invaders.
144
# Identify:
The function of the **skeletal system**.
To provide **structure** and **support** to the body, protect internal organs and store minerals.
## Footnote
It includes bones and joints.
145
# List:
What do **tendons** and **ligaments** do?
* Tendons attach muscles to bones.
* Ligaments attach bones to other bones.
## Footnote
They are crucial for movement.
146
# Define:
Evolution
A **change in the genetics** within a population over time.
## Footnote
This definition can be further refined as one learns more about population genetics.
147
# List:
The basic principles of **Darwinian evolution**.
* **Populations evolve** rather than individuals.
* Evolution occurs due to existing **genetic variation**.
* Differential reproduction rates based on **genotype**.
* **Natural selection** drives reproduction rates.
## Footnote
These principles highlight how **environmental pressures influence evolution**.
148
Who proposed the **theory of natural selection**?
**Charles Darwin** and **Alfred Wallace** in 1858.
## Footnote
Natural selection is the agent which determines a differential **rate of reproduction**.
149
# Explain:
The concept of '**survival of the fittest**' in the context of **natural selection**.
It refers to **members of a population that are more successful** at finding food and mates, escaping predation and thus **having more descendants**.
150
# Define:
Evolutionary adaptation
The mechanism by which an animal or plant alters itself to accommodate its changing environment.
151
# List:
The three types of **adaptation**.
* Behavioral adaptation
* Physiological adaptation
* Structural adaptation
152
# Explain:
The **relationship** between *natural selection* and *adaptation*.
**Natural selection** is the process that **facilitates** the passing on of **favorable adaptations** to offspring.
