9th Grade Biology Final Exam Study Guide

Flashcards for 9th Grade Biology Final Exam Review

What are the three major parts of the cell theory?

All living organisms are composed of one or more cells; the cell is the basic unit of life; all cells are produced from other cells.

In what year did Hans & Zacharias Janssen produce the first compound microscope?

1590

Who was the first person to observe cork under a microscope and coin the term 'cells'?

Robert Hooke in 1665

Who first observed living organisms (protozoa) under a microscope and called them 'animalcules'?

Anton van Leeuwenhoek in 1680

Who discovered that all plants are made of cells?

Matthias Schleiden in 1838

Who discovered that all animals are made of cells?

Theodor Schwann in 1839

Who discovered that all living cells come from other cells?

Rudolph Virchow in 1855

What are three components of the modern cell theory?

Energy flow occurs within cells; hereditary information (DNA) is passed on from cell to cell; all cells have the same basic chemical composition.

What limits the size of a cell?

The surface area to volume ratio.

What four components do prokaryotic and eukaryotic cells have in common?

Cell membrane, cytoplasm, DNA, and ribosomes.

Name three differences between prokaryotic and eukaryotic cells.

Prokaryotes are smaller and simpler, lack a nucleus, and lack membrane-bound organelles; eukaryotes are larger and more complex, have a nucleus, and have membrane-bound organelles.

Give two examples of prokaryotic cells.

Archaea and Bacteria

Give four examples of eukaryotic cells.

Plants, Animals, Fungi, and Protozoa

What is the function of the cell membrane?

Semi-permeable barrier that surrounds and protects the cell and its contents.

Where are proteins assembled?

Ribosomes on the rough endoplasmic reticulum

What organelle completes the modifications on proteins?

The Golgi apparatus

What two structures are found in a plant cell, but not an animal cell?

Cell Wall and Central Vacuole

What is the role of the cell membrane in transport?

Regulates what enters and exits the cell.

Describe the fluid mosaic model of the cell membrane.

The phospholipid bilayer acts like a liquid, with lipids and proteins moving laterally within the bilayer, creating a constantly changing pattern.

What is selective permeability?

The ability of a membrane to allow some substances to pass through more readily than others.

What is a concentration gradient?

The difference in the concentration of molecules across a distance.

Define passive transport. Give three examples.

The movement of molecules across the cell membrane without the use of energy. Examples: diffusion, facilitated diffusion, and osmosis.

Describe an isotonic solution.

A solution with equal concentrations of solutes inside and outside of the cell.

Describe a hypertonic solution.

A solution with a greater concentration of solutes outside of the cell than inside of the cell.

Describe a hypotonic solution.

A solution with a lower concentration of solutes outside of the cell than inside of the cell.

Define active transport.

The movement of molecules across a cell membrane from areas of lower concentration to higher concentration, requiring energy (ATP).

What is vesicular transport?

Using vesicles to transport large molecules into or out of the cell.

What is endocytosis? Give two examples.

The formation of a vesicle at the cell membrane to bring materials INTO the cell. Phagocytosis and Pinocytosis

What is exocytosis?

A vesicle fusing with the cell membrane to release materials OUT of the cell.

What is the key difference between autotrophs and heterotrophs?

Autotrophs produce their own food, while heterotrophs consume other organisms for energy.

What process do plants use to make food?

Photosynthesis

Give the equation for Photosynthesis

Sunlight + 6CO2 + 6H2O = 6O2 + C6H12O6

What is the main pigment in plants that absorbs sunlight?

Chlorophyll

Name three factors that affect the rate of photosynthesis.

Temperature, light intensity, and water availability.

What is the relationship between photosynthesis and cellular respiration?

Photosynthesis generates oxygen and glucose used in cellular respiration, while cellular respiration produces carbon dioxide and water used in photosynthesis.

Give the equation for Cellular Respiration

C6H12O6 + O2 = CO2 + H2O + 38 ATP

What is the difference between aerobic and anaerobic respiration?

Aerobic respiration requires oxygen, while anaerobic respiration does not.

Name the three stages of cellular respiration.

Glycolysis, Krebs Cycle (Citric Acid Cycle), and Electron Transport Chain.

Where in the cell does glycolysis occur?

Cytoplasm

Where in the cell does the Krebs Cycle take place?

Mitochondria

How much ATP does Glycolysis produce?

2 ATP

How much ATP does the Krebs Cycle produce?

2 ATP

How much ATP does the Electron Transport Chain produce?

32 ATP

What products are formed from Alcoholic Fermentation?

Ethyl Alcohol

What product is formed from Lactic Acid Fermentation?

Lactic Acid

What are two reasons why cells divide instead of continuing to grow larger?

The larger a cell becomes, the more demands the cell places on its DNA; if the cell grows too large, it will have trouble moving enough nutrients and wastes across the cell membrane.

What happens to the surface area to volume ratio as a cell increases in size?

The surface area to volume ratio decreases.

What is mitosis?

A form of asexual reproduction in which 2 genetically identical daughter cells are created from one mother cell.

What are the stages of mitosis?

Interphase, Prophase, Metaphase, Anaphase, Telophase, and Cytokinesis.

What is the result of mitosis in unicellular organisms?

New offspring by asexual reproduction.

What is the result of mitosis in multicellular organisms?

Growth and repair of the organism.

What happens if cells divide uncontrollably?

Cancerous tumors may develop.

What is meiosis?

A form of sexual reproduction that results in 4 genetically unique daughter cells created from one mother cell.

What are the stage of Meiosis?

Prophase I, Metaphase I, Anaphase I, Telophase I, Prophase II, Metaphase II, Anaphase II, and Telophase II

What is the key importance of Meiosis?

The chromosome number of the egg and sperm is reduced by half to ensure that the zygote will have the proper number of chromosomes.

What is a major disadvantage of asexual reproduction?

There is no genetic variation among the offspring.

What is a major advantage of sexual reproduction?

All of the offspring are genetically unique.

Where is DNA found in eukaryotic cells?

Only in the nucleus.

What are the three components of a nucleotide?

A phosphate group, deoxyribose sugar, and a nitrogenous base.

What is the shape of a DNA molecule?

Double helix (twisted ladder).

Name the four nitrogenous bases in DNA.

Adenine (A), Thymine (T), Cytosine (C), and Guanine (G).

Which nitrogenous bases pair together in DNA?

Adenine (A) always pairs with Thymine (T), and Cytosine (C) always pairs with Guanine (G).

What enzyme unwinds and separates the double helix during DNA replication?

Helicase

What is the purpose of SSB Proteins?

Bind to the separated strands of DNA to keep them from re-annealing.

What enzyme adds complementary nucleotides to the DNA template during replication?

DNA Polymerase

What are the four nitrogenous bases in RNA?

Adenine (A), Guanine (G), Cytosine (C), and Uracil (U).

What is Transcription?

The process in which a strand of DNA is converted into a strand of RNA.

Where does transcription occur?

In the nucleus.

What is Translation?

The process in which a strand of RNA is converted into a chain of amino acids

Where does translation occur?

In the cytoplasm, at the ribosome.

What is a codon?

Every three bases of mRNA

What is an anticodon?

A sequence of three bases that are complementary to a codon.

What is genetics?

The science that studies how genes are transmitted from one generation to the next.

Who is known as the 'father of genetics'?

Gregor Mendel

What is the law of dominance?

Some alleles are dominant, and others are recessive. A dominant allele can cover up or mask a recessive allele

What is the law of segregation?

If the offspring receives a dominant allele from one parent, that dominant trait will appear in the offspring. Recessive traits show up in the offspring only if the offspring receive recessive alleles from both parents.

What is the law of independent assortment?

When gametes are formed, the alleles of a gene for one trait segregate independently of the alleles of a gene for another trait.