Bio 1010- Exam 1 Study Guide

What is Life?

• It’s everywhere!!

• It’s Diverse

• Around 8.7 million species on Earth (doesn’t include bacteria)

• Some species aren’t even identified yet (i.e., depths of the ocean and ever-evolving bacterial species)

What are the Requirements of Life?

1. Must be organized

2. Requires materials and energy

3. Requires ability to reproduce and develop

4. Capability to respond to environment

5. Maintain an internal environment

6. Ability to adapt to environment(s)

What is the following picture showing?

This picture is showing that life is Hierarchical (one of life’s requirements)

When talking about the Requirements of Life, what does “Must be Organized” mean?

It means that life is Hierarchical

• (smallest)

  • Atom

  • Molecule

  • Cell

  • Tissue

  • Organ

  • Organ System

  • Organism

  • Species

  • Population

• (largest)

What is: Atom?

Smallest unit of an element

What is: Molecule?

Two or more atoms joined together

What is: Cell?

Membrane-bound unit that contains fundamental molecules of life; all living organisms have cells

What is: Tissue?

Group of cells with common structure and function

What is: Organ?

Tissues that function together for a specific task

What is: Organ System?

Several organs that work together

What is: Organism?

An individual that contains organ systems

What is: Species?

Group of similar, interbreeding organisms

What is: Population?

Organisms of the same species within an area

When talking about the Requirements of Life, what does “Requires materials and energy” mean?

• We need energy to survive and maintain our organ system

• Food —> nutrients —> energy (ability to do work)

  • Plants make their own food using Carbon Dioxide, Water, and Sunlight (Autotrophs)

  • Humans must acquire materials and energy by eating foods from their environment (Heterotrophs)

• Some nutrients are broken down to build things we need, such as proteins = metabolism

• Ultimate energy source for all life on Earth = sun

What is: Metabolism?

Some nutrients are broken down to build things we need, such as proteins

What is: Sun?

It’s the ultimate energy source for all life on Earth

What is: Chemical Cycling?

• Producers (plants) take in solar energy (from the sun), they’ll also use nutrients to make organic nutrients via photosynthesis

• Consumers (humans, mammals) take up those organic nutrients that are produced by the producers

• Decomposers recycle the nutrients from dead organisms and allows for inorganic nutrients to be returned to the producers again

Inorganic Nutrients is without _____; Organic Nutrients is with _____

carbon (x2)

What is: Energy Flow?

Sun —> plants —> other organisms —> returns to atmosphere as heat

When talking about the Requirements of Life, what does “Requires ability to reproduce and develop” mean?

• “Life comes only from life”

• Reproduction: make another organism like themselves

• Genes pass on to the next generation

  • Ensures that offspring has a new set of new & different characteristics

  • Mutations provide variation in genetic information

    • Not all mutations are bad — allows for evolution!

What is: Reproduction?

The process of making another organism like themselves

T or F: ALL mutations are bad

False, some mutations allow for evolution to occur

When talking about the Requirements of Life, what does “Capability to respond to environment” mean?

• We rely on information we receive AND perceive from the environment = stimuli

  • Ex: when you put a plant by a window, hormones within the plant detect sunlight, allowing the plant to bend toward the sun

What is: Stimuli?

We rely on information we receive and perceive from the environment

When talking about the Requirements of Life, what does “Maintain an internal environment” mean?

• Internal environments (cells, your body) must be stable

• This tendency toward a stable environment is called homeostasis

  • Ex: Body temperature, hunger

What is: Homeostasis?

Maintenance of a relatively constant internal environment by an organism, or even by a single cell

When talking about the Requirements of Life, what does “Ability to adapt to environment(s)” mean?

• Environments can change quickly or over long periods of time

• Either way, organisms must adapt to survive

• When an organisms becomes more suited for a new environment, it is believed to have adapted to that environment

  • In result, they live longer and produce more offspring (natural selection)

What is: Taxonomy?

The discipline of identifying and grouping organisms

What is: Systematics?

The study of evolutionary relationships between species

What is: Taxa?

The basic classification strategies (organized from most to least inclusive)

• Domain, Kingdom, Phylum, Class, Order, Family, Genus, and Species

What is the strategy to remember Taxa Groups?

• Dear King Philip Came Over For Great S3x

  • Domain, Kingdom, Phylum, Class, Order, Family, Genus, and Species

What are the 3 domains of life?

• Archaea

• Bacteria

• Eukarya

Why and how are organisms named?

They are named in a binomial fashion, created by Carolus Linnaeus

• First word = Genus, ALWAYS capitalized

• Second word = Specific epithet, ALWAYS lowercase

What’s the difference between typing and writing an organisms name?

• Typing = names are always italicized

• Writing = names are always underlined

T or F: Escherichia Coli is the correct way to format an organisms name

False, the specific epithet should be lowercase (Escherichia coli)

What is: Scientific Method?

Standard series of steps used in gaining new information

What is: Observation?

Formal way of watching the natural world

What is: Hypothesis?

A possible explanation for a natural event (must be an informed statement)

What is: Experiment?

Series of procedures to TEST a hypothesis

What are some challenges facing science?

1. Climate Change

2. Biodiversity and Habitat Loss

3. Diseases

Why is Climate Change a challenge that faces science?

• Global warming

  • Increase in Carbon Dioxide and other gases in the atmosphere absorb and radiate heat back to earth via the Greenhouse Effect

Why is Biodiversity and Habitat Loss a challenge that faces science?

• Biodiversity: total number and relative abundance of a species, gene variability, and different ecosystems in which they live

• Extinction: death of a species

• Threats to these mostly due to anthropogenic (human-caused) effects

  • Ex: Coral reefs and tropical rainforests

What is: Greenhouse Effect?

The increase of Carbon Dioxide and other gases in the atmosphere, that are absorbed and radiates heat back to earth

• Like a sheet around Earth

What is: Biodiversity?

Total number and relative abundance of a species, gene variability, and different ecosystems in which they live

What is: Extinction?

Death of a species

What does anthropogenic effects mean?

They are human-caused

Why is Diseases a challenge that faces science?

• Avian flu, swine flu, SARS, and MERS are emerging diseases because they are new to humans

• Reemerging diseases are also of concern, but not as much because of low incidence levels of humans (ex: Ebola)

  • Bacteria grow very quickly (divide every 20 min) —> faster mutation rates —> can evolve faster —> can surprise us with diseases faster!

Life is ____, so we’ve got to have a way of organizing it so that it makes sense to us

diverse

Life has ___ _______ (in order for life to exist)

6 requirements

Doing science is ____ _____, mind boggling, yet ______

time consuming; rewarding

There are many _____ facing scientists today

challenges

Who was Anton van Leeuwenhoek, and why is he important?

He made some of the earliest microscopes

Who was Robert Hooke, and why is he important?

• He confirmed Leeuwenhoek’s findings

• Was the first to term the word “cell”

  • Was observing cork from a plant when he coined this term

What is: Cell Theory?

1. Organisms are made up of basic living units (cells)

2. All cells come from previously existing cells

What are the two types of cells?

• Prokaryotic

• Eukaryotic

What is: Prokaryotic Cell?

Lacks a membrane-bound nucleus

• Includes bacteria and archaea

What is: Eukaryotic Cell?

Contains a membrane-bound nuclei that contains genetic info

• Includes plants, fungi, animals, and protists

All cells (regardless of prokaryotic or eukaryotic) are surrounded by a _____ ______!!

Plasma Membrane

What is: Plasma Membrane?

• Made of a phospholipid bilayer (containing phosphates and lipids)

• Hydrophobic tails (water-fearing) are inside

• Hydrophilic heads (water-loving) face outwards

• Can be fluid - allows certain molecules to pass through freely

  • Fluid mosaic model - molecules are constantly moving

• Can also be restrictive - proteins within the membrane that are selective to molecules that can leave/enter cell

What are the functions of the Plasma Membrane?

1. Separates contents of cell from surrounding environment

2. Regulation of molecule passage (physically protects the cell)

Identify the Domain of life (Archaea, Bacteria, or Eukaryotes)

• Plasma Membrane: Yes

• Nucleus: No

• Ribosomes: Yes

This is describing BOTH Archaea and Bacteria

Identify the Domain of life (Archaea, Bacteria, or Eukaryotes)

• Plasma Membrane: Yes

• Nucleus: Yes

• Ribosomes: Yes, larger than prokaryotic

This is describing Eukaryotes

What are the defining characteristics of a Eukaryotic Cell?

• Distinguishing feature: possession of a nucleus

• Some have cell walls that surround the plasma membrane (NOT animal cells and some protists)

• Organelles: any well defined sub-cellular structure that performs a particular function

What is: Organelles?

Any well defined sub-cellular structure that performs a particular function

Both animal and plant cells are ______

eukaryotic

When talking about Eukaryotic Cells, the plant cell has a ____ ____, but the animal cell doesn’t

cell wall

What Organelles does the Animal Cell include?

• Cytoskeleton

• Cytoplasm

• Nucleus

• Endoplasmic reticulum

  • Rough

  • Smooth

• Mitochondria

• Golgi apparatus

• Lysosome

What is the function of: Cytoskeleton?

Maintains cell shape & movement of cell parts

What is the function of: Cytoplasm?

Semifluid matrix outside nucleus that contains organelles

What is the function of: Nucleus?

“Brain” of cell that contains genetic material

What is the function of: Rough ER?

Has ribosomes; processes proteins

What is the function of: Smooth ER?

Doesn’t have ribosomes; makes lipids

What is the function of: Mitochondria?

Carries out respiration and makes ATP (energy)

What is the function of: Golgi apparatus?

Processes, packages, and secretes cell products

What is the function of: Lysosome?

Vesicle that digests macromolecules

What is: Endosymbiotic Theory?

• It proposes that a prokaryotic cell entered a host cell, and then they began to live together in symbiosis

  • Explains origin of mitochondria, chloroplasts, and internal membranes of eukaryotic cells

  • Proposes that a chloroplast used to be a photosynthetic bacterium (called Cyanobacteria)

Who proposed the Endosymbiotic Theory?

It was proposed by Lynn Margulis

T or F: eukaryotic cells require constant maintenance, regulation, and organization

True, this is because they are extremely complex systems that are squeezed into a teeny-tiny cell

What type of cell is the following picture showing?

This is showing a plant cell

What type of cell is the following picture showing?

This is showing an animal cell

T or F: internal environmental conditions are always constant

False, the internal state of body is in a constant dynamic state

What happens if this internal state (of the body) is disrupted?

We get disease

What is: Disease?

It’s an abnormality in your body’s normal processes that significantly impairs homeostasis

What are the three Components of Homeostatic Mechanisms?

• Sensor/receptor

• Control Center

• Effector

When talking about the Components of Homeostatic Mechanisms, what does the sensor/receptor do?

It detects change in internal conditions

When talking about the Components of Homeostatic Mechanisms, what does the control center do?

It directs the response to bring conditions back to normal. Once normal, the sensor is no longer activated

When talking about the Components of Homeostatic Mechanisms, what does the effector do?

This is organ/tissues that receive the information from the control center and act to bring about change(s) to maintain homeostasis

Identify the Components of Homeostatic Mechanisms when talking about Body Temperature

• Sensor/receptor: thermoreceptors found in your skin

• Control center: hypothalamus

• Effector: muscles, blood vessels

What are the two types of Homeostatic Mechanisms?

• Negative Feedback

• Positive Feedback

What is: Negative Feedback?

It’s the primary homeostatic mechanism that keeps a variable as close as it can to a particular value

What is a non-biological example of Negative Feedback?

• Air Conditioning

  • Goal: to keep the air as close to the set temperature of the thermometer

What are biological examples of Negative Feedback?

• Body temperature regulation

  • Goal: to keep your temperature as close as it can to optimum degrees

• Blood sugar regulation

  • Goal: to keep your glucose levels as close as it can to optimum value

What is: Positive Feedback?

It’s mechanisms that bring about rapid change in the same direction as the stimulus

What are biological examples of Positive Feedback?

• Blood clotting

  • Platelets go to injured area and release factors that stimulate further clotting

• Birth

  • As labor continues, cervix is continually stimulated and contractions continue and become stronger until the baby is born

What is all included in the Integumentary System?

Skin and its accessory organs (nails, hair, oil glands, sweat glands)

What is the functions of the Integumentary System

• The main function of the skin is protection

  • Protects underlying tissue from physical trauma

  • Protects against pathogen invasion

  • Prevents water loss

• Other functions include:

  • Helps regulate body temperature

  • Synthesizes vitamin D

  • Allows us to communicate through touch via sensory receptors

What are the 3 Regions/Layers of the Skin?

1. Epidermis

2. Dermis

3. Subcutaneous layer

What is the following picture showing?

This is showing the 3 regions/layers of the skin

T or F: there is only one type of epithelial cells

False, there are many different orientations of these cells

What are characteristics of the Epidermis Layer of the Skin?

• First/top layer of “skin”

• Stratified squamous epithelium

  • Stratum corneum: outermost layer

  • Stratum basale: innermost layer

• Melanocytes give skin its color and protects against UV rays

• Cells become hardened and flat because these cells produce keratin

• Fingerprints and footprints — made by thick layer of keratinized cells organized in spiral/random patterns