Biology Semester Exam

What is science?

1. Science is the way of gathering and analyzing evidence about the natural world

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What are the goals of science

* To provide natural explanations for events in the natural world. 
* To use those explanations to understand patterns in nature and to make useful predictions about natural events.
* To provide solutions to problems.

The process of science

* Science deals only with the natural world. 
* Scientists collect and organize information in an orderly way, looking for patterns and connections among events. 

Order of Scientific Methodology

1. Observing and Asking Questions
2. Inferring and Forming a Hypothesis
3. Designing Controlled Experiments
4. Collecting and Analyzing Data
5. Drawing Conclusions

What is a hypothesis?

A scientific explanation for a set of observations that can be tested

**What are the 2 groups of any experiment?**

**An experimental group and a control group.**

**What are the 2 variables of any experiment?**

**The two variables are independent and dependent variables.**

What is an independent variable?

**The independent variable is the variable that is added to the experiment.**

What is a dependent variable?

**The dependent variable is the result of the change.**

Example of an independent variable?

**How much food you eat**

Example of a Dependent Variable

**Weight loss**

What is biology?

**Biology is the study of life.**

What is the difference between growth and development?

**Growth is the increase in** ==__mass and volume__==**,**

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**Development is the change in** ==__**characteristics**__== **over time.**

List three characteristics of life and explain them

1. **Living things are based on a universal genetic code (everything living in the universe is made up of DNA).**
2. **Living things get and use material and energy (metabolism and energy is needed to survive).**
3. **Living things respond to the environment (Ways organisms respond to stimulus)**

What is a stimulus?

**A stimulus is a signal to which a living thing reacts**

What are three examples of how humans respond to stimuli?

**A person moves his hand away from a hot plate**

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**A person shivers or puts on a jacket when it’s cold**

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**A person eats when they feel hungry**

Compare and contrast the types of reproduction:

==**Both require DNA and offspring acquire the characteristics of the parent(s)**==

**Sexual reproduction requires male and female parts**

%%**Asexual reproduction requires one parent only (like bacteria; divide and reproduce by simple binary fission)**%%

What is homeostasis?

**It is the maintenance of a stable internal environment.**

**Three examples of homeostasis in the human body**

* **Body temperature: 37 degrees Celsius**
* **Blood Pressure: 120/80 mm Hg**
* **Heart Rate: 70 beats/min.**

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**Why do living things need materials and energy?**

**To grow, develop and reproduce**

The definition of metabolism

**It is the chemical reactions that living things carry out to build up or break down materials**

Fill in the blank: ---- is a stable internal environment

Homeostasis

Fill in the blank:----Is one of the two groups in an experiment---- is the other one

Control group and experimental group

What is evolution?

Evolution is the change over time.

**Where do scientists find evidence of evolution?**

**In parts of living things, proteins, DNA and fossils**

Tell me **5 levels of organization of living things. Give me examples of each one.**

1. **Cell Example: skin cells**
2. **Tissue  Example: Connective tissue**
3. **Organ  Example: Stomach**
4. **Organ system Example: Digestive system**
5. **Organism: Example: A human being**

What are common characteristics of cells?

**Every cell has a cell membrane, cytoplasm, ribosomes and DNA**

**What are the two types of living things according to the number of cells they have?**

* **Unicellular organisms: They’re made up of one cell only**
* **Multicellular organisms: They’re made up of more than one cell**

Give examples of Multicellular and Unicellular organisms.

Bacteria=Unicellular

Animals=Multicellular

**Where is the information about all your characteristics stored?**

**DNA**

1. **What are examples of predictions that doctors can make about a person from their DNA?**

**Risk of getting cancer**

**Color of children’s hair**

**How are producers different from consumers?  Give examples of each**

* **Producers can make their own food. Ex: Plants**
* **Consumers: Get their food. Ex: Animals**

**What are the scientific terms for ‘producers’ and ‘consumers’?**

**Producers are autotrophic organisms. Ex: Plants**

**Consumers are heterotrophic organisms. Ex: Animal**

**How is the offspring of sexually reproducing parents different from the offspring of asexually reproducing parents?**

**Sexual reproduction produces offspring that is similar to their parents**

**Asexual reproduction produces offspring that is identical to their parents**

**List 5 examples of problems with homeostasis**

* **Fever**
* **High or low blood pressure**
* **High or low blood sugar level**
* **Low Ca or vitamin D levels**

**Explain reasons why organisms need to change their characteristics over time.**

**To adapt to the changes in their environment**

**What is the difference between ‘adaptation’ and ‘acclimation’?  Give examples**

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%%**Adaptation happens over generations.  Ex.: Giraffes and whales changed their characteristics to adapt to their environment**%%

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%%**Acclimation happens in an organism’s lifetime.  Ex.: Sheep grow very thick wool in cold, damp climates.**%%

**Give examples of how 3 different human body cells have different structures to serve their functions**

* **Skin cells are flat and the top layer is dead to cover and protect the body**
* **Nerve cells have long extensions to send and receive electrical impulses**
* **White blood cells can squeeze and move in order to reach areas of pathogens to fight against disease**

**What are the common characteristics of all living things at the molecular level?**

**All living things have DNA, need water, proteins and other organic molecules**

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**There are 5 different types of Symbiosis:**

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* **Mutualism**
* **Commensalism**
* **Competition**
* **Predation** 
* **Parasitism**

The steps to a biosphere:

1. BIOSPHERE
2. ECOSYSTEM
3. COMMUNITY
4. POPULATION
5. ORGANISM

**List the 5 main fields of Biology and what they help us to understand:**

* **Global Ecology:** 

**To learn about people’s global impact on all life on Earth**

* **Biotechnology:** 

**To read, write and edit the genetic code in order to correct or replace genes that cause diseases.**

* **Building the tree of life:**

**To gather information about all organisms and put together a single ‘Tree of All Life”.**

* **Ecology and Evolution of Diseases:**

**To understand how germs change and react to their surroundings in order to keep people healthy**

* **Genomics and Molecular Biology:**

**To study and analyze the DNA molecule in order to learn about growth, development and the history of life on Earth**

**Define Ecology:**

1. **Ecology is the study of interactions between organisms and their physical environment.**

**Who is an ecologist?**

**An ecologist is a person who studies the interactions between organisms and their physical environment.**

**Give one example of each of the 2 factors that form any environment**

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**Biotic: Plants**

**Abiotic: Water**

What are the two factors that form an environment?

Biotic(alive)

Abiotic(dead)

**What are the 3 methods that are used to study ecology?**

**-Observations**

**-Experimenting** 

**-Modeling**

**Compare and Contrast Autotrophs and Heterotrophs?**

**Autotrophs are producers, while heterotrophs are consumers. Autotrophs make their own energy, while heterotrophs feed on other organisms to get energy.**

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**What are other scientific terms that could be given to autotrophs and heterotrophs?**

**Two terms that could be given to autotrophs and heterotrophs are producers and consumers.**

**List and give one example of each of the 6 types of consumers**

**Herbivores: Consumers that eat plants. Carnivores: Consumers that eat other animals.**

**Omnivores: Consumers that eat both plants and animals. Scavengers: Consumers that eat the remains of other animals that have been killed by predators or that have died of other causes.**

**Decomposers: Consumers that break down organic matter into small pieces called detritus.** 

**Detritivores: Consumers that feed on detritus (small pieces of dead and decaying plant and animal remains).  They commonly** 

What is the difference between Detritivores and Decomposers?

While decomposers break down dead, organic materials, detritivores—like millipedes, earthworms, and termites—eat dead organisms and wastes.

**Compare and Contrast Food chains and Food webs**

**They are both steps for which energy flows. While the food chain is a simple series of steps of how energy is transferred, the food web is a network of interconnected food chains.**

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1. **Draw a diagram showing an example of a food chain with 5 organisms.  Draw the arrows pointing from what is being eaten to what eats it**

**Grass→grasshopper→frog —>snake—>fox**

Draw a food web

What is an energy pyramid?

**An energy pyramid is a diagram that shows energy transfer from each trophic level.**

Label an energy pyramid.

**What are the 3 types of ecological pyramids?**

**The three types of ecological pyramids are: energy pyramid, pyramid of numbers, and pyramid of biomass**

**What are the names of the 2 organisms in Predation?**

**The prey and the predator**

**What are the names of the 2 organisms in Parasitism**

**The parasite and the host**

**What are 2 outcomes of competition?**

**The two outcomes are 1.One organism wins the other loses and is eliminated from the Habitat 2.Dividing resources.**

**What is symbiosis?**

**Symbiosis is close interactions between two organisms.**

**What are 3 types of symbiosis?**

**Mutualism, commensalism, and parasitism.**

**Give one example of mutualism showing how the 2 organisms benefit:**

**An example is the fish that helps clean the shark's teeth. The shark gets clean teeth and the fish gets food.**

**Compare and contrast habitat and niche**

**A habitat is an organism's home, while a niche is an organism's job in its environment.All organisms have a niche and a habitat.**

Give an example of commensalism

Barnacles get shelter on the whale and the whale is not harmed or bothered (0,+1)

Give an example of parasitism:

A tick on a dog. (-1,+1)

**What are the different types of nutrients that your body needs?**

Water: Make 75% of your cells and body weight

Nucleic acids: nucleotides (DNA-RNA)

Proteins: amino acids (CHICKEN, MEAT, BEANS)

Lipids: Glycerol and fatty acids (OIL and BUTTER)

Carbohydrates: monosaccharides (RICE BREAD PASTA)

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What are enzymes?

**They are substances that are made inside the body from proteins.**

**What are enzymes made up of?**

**Enzymes are made up of proteins.**

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**What are the functions of enzymes?**

**Their function is to catalyze chemical reactions.**

**Compare and contrast DNA and ATP**

1. **Both are molecules, but each of them stores something different.**

Fill in the blank:

\-----Discovered and named the cell.

Robert Hooke

Tell me facts about Robert Hooke

He was an English scientist

He was a scientist

He discovered the cell

He named it cell, because  it reminded him of the tiny rooms where monks used to live.

1. **How does Leeuwenhoek’s work compare to Hooke’s?**

**Hooke discovered what cells are in general, but Leeuwenhoek looked at specific details (microorganisms that live in water).**

**What are the 3 parts of the cell theory?**

1. **All living things are made of cells**
2. **Cells are the basic units of structure and function in living things**
3. **New cells come from preexisting cell**

1. **Write the names of the scientists who wrote the cell theory and write their professions and nationalities**

**Schleiden who was a Botanist(German),**

 **Schwann who was a Zoologist(German),**

**Virchow who was a Physician(German).**

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**Compare and contrast the 2 types of cells and give one example of each**

**Prokaryotic cells and eukaryotic cells are both cells and they both have a cell membrane, cytoplasm, DNA, and ribosomes. Prokaryotic cells don’t have a nucleus and they are mostly unicellular organisms. Eukaryotic cells have a nucleus and they are mostly multicellular organisms.**

**What are the 4 structures that are found in all kinds of cells?**

**The 4 structures that are found in all kinds of cells are: cell membrane, cytoplasm, DNA, and ribosomes**

What are is the function of cell membrane?

Protects the cell and it controls what leaves and enters it

What are the functions of cytoplasam?

__***Holds organelles in place***__ 

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__***Allows organelles for movements***__ 

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__***Gives the cell its shape***__ 

What are the functions of __***Cell wall?***__

**Gives strength and shape the plant , acts like bones.**

**What are functions of the Nucleus?**

__***Carries the DNA***__ 

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__***Control center of the cell***__ 

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__***Makes ribosomes***__ 

What are the functions of Mitochondria?

__***It provides the cell energy through cellular respiration***__ 

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__***Energy is stored in mitochondria in the form of ATP molecules***__

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THE POWER HOUSE OF THE CELL

What are the functions of chloroplasts?

__***Provides the plant cell with food through photosynthesis***__

What are the functions of Ribosomes?

__***They make proteins***__ 

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__***A) free ribosomes make proteins that are used in the cytoplasm***__ 

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__***B) Attached ribosomes make protein to be used in the cell membrane or out.***__

What are the functions of lysosomes?

__***They break down excess  substances (waste)***__

What are the functions of vacuoles

__***Storing fluid for the plant***__ 

__***It destroys waste***__ 

__***Some plants store toxic substances to protect predators.***__

What are the functions of vesicles?

__***Transports substances or molecules inside or outside the cell***__ 

What are the functions of Golgi Apparatus?

__***Modifies substances made inside of cell***__

What are the functions of Smooth ER?

* __***regulates the calcium level in the cell***__ 
* __***Makes hormones like steroids (cortisone)***__
* __***Detoxifies substances in the liver***__ 

What are the functions of rough ER

__***Transports the proteins made on its surface to the cell membrane or outside of the cell***__ 

**List the organelles that are found in animal cells only.  Write their functions**

**Lysosomes: They break down excess substances**

**List the organelles that are found in plant cells only.  Write their functions**

%%**Cell wall**%%**:gives strength to the plant acts like bones**

%%**Chloroplast**%%**: provides the plant cell with food through photosynthesis.**

%%**Vacuoles**%%**: stores fluid for the plant and it destroys waste**

**List the organelles that are surrounded by 2 membranes.**

**-Nucleus**

**-Mitochondria**

**-Chloroplasts**

**List the organelles that are not surrounded by any membrane.  What are their 2 types and their functions?**

**Ribosomes: Free ribosomes: make proteins that used in the cytoplasm Attached: make protein to be used in the cell membrane.**

Describe phospholipid molecules:

 **Each molecule has one head and two tails. The heads are hydrophilic and the tails are hydrophobic.**

**Describe the structure of the cell membrane:**

**The cell membrane is made up of a lipid bilayer. The lipids are phospholipid molecules. Each molecule has one head and two tails. The heads are hydrophilic and the tails are hydrophobic.** 

**Compare and contrast the 2 types of transport**

**Passive transport doesn’t require energy and goes down the concentration gradient**

**Active transport requires energy and goes up the concentration gradient**

**Explain why passive transport doesn’t require energy and why active transport does.**

**Passive transport doesn’t require energy, because substances will move from an area of high concentration to an area with low concentration, while active transport goes from low concentration to high concentration**

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Example of passive transport

When a raisin is soaked in water the water moves inside the raisin by the process of osmosis and it swells.