Unit 8 (Full-Length)

How is a population different from a community?

- Population: multiple organisms of the same species living together

- Community: multiple populations of different species living together

How is a community different from an ecosystem?

An ecosystem is a community plus all of the abiotic factors in the environment (ex: temperature, precipitation)

How is a population different from a community?

- Population: multiple organisms of the same species living together

- Community: multiple populations of different species living together

How is a community different from an ecosystem?

An ecosystem is a community plus all of the abiotic factors in the environment (ex: temperature, precipitation)

List the levels of biological organization from the cell to the biosphere

Cell, tissue, organ, organ system, organism, population, community, ecosystem, biome, biosphere

List the levels of taxonomic organization from broadest to most specific

Domain, kingdom, phylum, class, order, family, genus, species

What two levels of organization does a specific scientific name include?

Genus and species

Give an example of a biome

Desert, tundra, rainforest, grassland

What are taxonomy and biodiversity?

- Taxonomy: field of biology that classifies organisms, organizing them based on similar characteristics

- Biodiversity: the variety of organisms considered at all levels, from populations to ecosystems

What are the three domains of life, and are they prokaryotic or eukaryotic?

- Bacteria: prokaryotic

- Archaea: prokaryotic

- Eukarya: eukaryotic

What makes up the DNA of bacteria?

A nucleoid (one circular DNA chromosome) and plasmids

What are the three shapes of bacteria?

Coccus, bacillus, spiral

What does it mean if a bacteria is gram-positive or gram-negative?

- Gram-positive: cell wall is high in peptidoglycan, shows purple dye

- Gram-negative: cell wall has a thin layer of peptidoglycan with a polysaccharide layer on the outside, doesn't show purple dye but instead appears red

Give three examples of ways that bacteria are helpful and not harmful

- They make up foods like yogurt, cheese, and pickles

- Bacteria on our skin help to prevent infections

- Bacteria in our gut help us digest our food

Do bacteria reproduce by asexual or sexual reproduction?

Asexually, through binary fission

What are four ways that genetic variation is introduced in bacteria?

Mutation, conjugation, transformation, and transduction

Mutation

Random change in genetic material

Conjugation

DNA transfer between two cells

Transformation

Uptake of foreign DNA from the organism's surroundings

Transduction

When a virus transfers genes between bacteria

What are several characteristics and structures of viruses?

- Nonliving ("biological entities)

- Do contain genetic material (DNA or RNA)

- Depend on a cell (host) to survive

- Capsid (external protein coat)

- Nucleic acid core (DNA or RNA)

How is the lytic cycle different from the lysogenic cycle for viral reproduction?

- Lytic: virus immediately makes copies and bursts the host cell

- Lysogenic: viral DNA hides in host cell's DNA and stays "dormant" until expressed

What do viruses, bacteria, and fungi ultimately disrupt in an organism?

Homeostasis: the stability of the internal environment and the mechanisms that maintain the stability

What are the main scientific contributions of Louis Pasteur and Robert Koch?

- Louis Pasteur: discovered fermentation and decay were caused by living microorganisms ➜ pasteurization process

- Robert Koch: discovered a universal method for determining whether a specific bacterium causes a certain disease

What are the four main causes of disease?

- Presence of disease-causing bacteria, virus, or fungi

- Hereditary factors

- Environmental factors

- Gene mutations (uncontrolled cell division = cancer)

What are the three reasons why bacteria and viruses are so harmful?

- They can live in a variety of environments

- We can't see them

- They reproduce quickly

Describe how bacteria cause sickness in their host

Invade organisms, use cell for food, break down healthy cells and tissues, and release toxins that can travel to different tissues in the body through the bloodstream

Describe how viruses cause sickness in their host

Target specific tissues, invade the cells, hijack the protein expression mechanisms, and copy themselves

Define pathogen, antigen, and antibody

- Pathogens: organisms or viruses that can cause disease

- Antigen: part of the pathogen that the body learns to recognize that produces an immune response

- Antibodies: proteins that are used by the immune system to tag the pathogens for destruction

Differentiate between innate and adaptive immunity

- Innate: non-specific, all plants and animals, rapid 0-96 hr response times, includes defense cells and natural killers

- Adaptive: specific to pathogens, vertebrates only, >96 hr response time, uses B and T cells

Do antivirals kill viruses like antibiotics kill bacteria?

They don't "kill" the virus, they just shorten the length of symptoms

Explain how vaccination works and what herd immunity is

- Vaccination uses substances to stimulate your immune system to guard against attack (used to prevent viral and bacterial disease)

- Herd immunity is when a sufficient % of a population becomes immune, effectively protecting the remaining vulnerable individuals

How are bacteria and archaea different? What is something very unique about archaea?

- Differ in their genetics, biochemistry, and ecology

- Some are extremophiles, living in environments with extremely high or low temperatures, or extreme salinity

Describe what happens to the immune system during AIDS or an allergic reaction

- AIDS: weakens the immune system by destroying helper T-cells

- Allergic reaction: immune system overreacts to a harmless substance

Characteristics of vascular plants (ex: tomato)

- Contain vascular tissue

- Allows them to transport water and sugars throughout

- Have specialized organs (roots, stems, leaves)

Characteristics of nonvascular plants (ex: moss)

- Do not have vascular tissue

- Smaller bc they can't transport water up stem

- Water is absorbed via osmosis

- Lack true leaves, stems, or roots

What are two ways that plants resist herbivores?

Plants may evolve physical defenses like thorns or produce chemical toxins to deter herbivores

What is the correct ordering for what happens to food once you eat it?

The digestive system breaks down food into usable nutrients, which are then absorbed into the bloodstream and transported throughout the body by the circulatory system to be used for energy, growth, and repair.

Mouth ➜ esophagus ➜ stomach ➜ small intestine ➜ large intestine (colon) ➜ rectum

How is communication different between the nervous system and endocrine system?

- Nervous system: physically connected network of cells, tissues, and organs that controls thought, movement, and simpler life processes (works quickly)

- Endocrine system: a collection of physically disconnected organs that helps to control growth, development, and responses to your environment (works slowly)

What is a hormone, and how are they used by the endocrine system?

The chemical signals made by the endocrine system for regulation of the body

- Released into the bloodstream and will only interact with cells that have specific receptors, prompting the cell to make proteins or enzymes

What is a neuron, what are the three types, and what do they do?

A specialized cell that stores information and carries messages within the nervous system and between other body systems

- Sensory: detect stimuli and transmit signals to the brain

- Interneurons: receive signals from sensory neurons and relay them to the brain and spinal cord

- Motor: pass messages from nervous system to other tissues in the body such as muscles

Which parts of the endocrine system are found in the brain? Which part is also part of the nervous system?

- The hypothalamus, pituitary gland, and pineal gland are found in the brain

- The hypothalamus is part of both the endocrine system and the nervous system

What processes do the thyroid, adrenal glands, and pancreas control in the endocrine system?

- Thyroid: metabolism, growth, and development

- Adrenal glands: breathing rate, blood pressure, and alertness

- Pancreas: production of digestive enzymes, glucose storage and usage

What is the difference between the central nervous system and the peripheral nervous system?

- Central: the brain and spinal cord (interprets and stores messages)

- Peripheral: a network of nerves that transmits messages to the CNS and from the CNS to other organs in the body (contains a sensory and motor system)

How is communication in the nervous system both chemical and electrical?

- Neurons communicate electrically and chemically

- In synapses, electrical signals are converted into chemical signals (neurotransmitters), which are released between the neurons

What are the three main parts of the brain?

Cerebrum, cerebellum, and brain stem

What is the difference between the somatic and autonomic nervous systems?

- Somatic: regulates movements over which you have voluntary control

- Autonomic: controls automatic functions that you don't have to think about (digesting food, maintaining homeostasis)

What are the main functions of the female and male reproductive systems?

- Female: to produce egg cells and to provide a place where a fertilized egg can develop

- Male: to produce sperm cells and to deliver them to the female reproductive system

Which hormones control male and female sexual characteristics, and where are they produced?

- Female: estrogen, in the ovaries

- Male: testosterone, in the testes

Which part of the female reproductive system supports pregnancy?

The uterus

Extra information

- Be able to label the male and female reproductive systems

- Know about other body systems (functions, main structures, connections, etc.)