SACE Stage 2 Biology: Topic 2

What is the cell theory?

Cells are the structural unit of organisms

cells are the functional unit of life

cells are derived from pre-existing cells

cells contain genetic information

cells are the smallest independent living unit of life

What classifies a cell?

Grow and reproduce, use energy, respond to stimuli, control internal environment

What does the phospholipid bilayer consist of?

Phospholipids, cholesterol, glycoprotein, extrinsic protein, intrinsic protein

What is the role of cholesterol in the cell membrane?

Regulate fluidity and permeability

What does the fluid mosaic model mean?

Fluid: freely laterally moving phospholipids

Mosaic: imbedded proteins

What is a prokaryotic cell?

A cell with no nucleus or membrane bound organelles

How is DNA held in a prokaryotic cell?

A single circular looped chromosome

How is DNA held in a eukaryotic cell?

Multiple linear chromosomes

What is a eukaryotic cell?

Cell with a nucleus and membrane bound organelles

What is the role of a nucleus?

Control the structure and function of the cell

What does the nucleus contain?

DNA and the nucleoli

What is the role of the nucleoli?

Synthesise ribosomes from rRNA

What is the role of mitochondria?

Aerobic respiration

What is the structure of the mitochondria?

Double membrane, christae, matrix

What is the role of the chloroplast?

Photosynthesis

What is the structure of the chloroplast?

Double membrane, lamellae, grana, stroma

How are the grana produced?

Lamellae to thylakoid disks to granum to grana

Where is the chlorophyll situated in chloroplasts?

On the thylakoid disks

How is glucose stored in chloroplasts?

As starch molecules

What is the role of ribosomes?

Protein synthesis

Where are ribosomes located?

Rough endoplasmic reticulum

What is the role of the RER?

Protein synthesis an dtransplort

What is the RER composed of?

Ribosomes on a nuclear membrane

What is the role of the SER?

Lipid and steroid synthesis, alcohol and drug detoxification

What is the role of vacuoles?

Storage

What are vacuoles composed of?

Infolded membrane

What is the role of the Golgi body?

Package secretions and produce lysosomes

What is the role of lysosomes?

Digest and breakdown wastes, redundant organelles and apoptosis

What is the role of the centriole?

Produce spindle fibres in mitosis and meiosis

What are centrioles made of?

Microtubules

What is the role of the cytoskeleton?

Shape, movement, support

What is the cytoskeleton composed of?

Microtubules and microfilaments

What is the difference between plant and animal cell walls?

Plant cell walls are composed of cellulose

What is simple diffusion?

The movement of lipid soluble molecules with the concentration gradient

What is facilitated diffusion?

The movement of large, polar molecules through a protein channel with the concentration gradient

What is osmosis?

The net movement of water across a selectively permeable membrane from a hypotonic concentration to a hypertonic concentration

When does osmosis stop?

When equilibrium is reached and both solutions are isotonic

What happens to animal cells in hypotonic solution?

Lysis

What happens to animal cells in hypertonic solution?

Crenation

What happens to plant cells in hypotonic solution?

Turgid

What happens to plant cells in hypertonic solution?

Plasmolysis

What is active transport?

The movement of polar molecules through a protein channel against the concentration gradient

What is exocytosis?

The external release of cellular products

What is pinocytosis?

The intake of liquids

What is phagocytosis?

The intake of solids

What are active transport processes?

Active transport, exocytosis, endocytosis

What are passive transport processes?

Simple diffusion, facilitated diffusion, osmosis

What is an autotroph?

An organism that converts inorganic molecules into organic molecules

What is a heterotroph?

An organism that gets organic molecules from consuming other organisms

What is ATP?

Adenosine triphosphate

What is the structure of ATP?

Adenosine, ribose, 3 phosphate groups

What is the chemical equation for photosynthesis?

6CO2 + 6H2O + light + chlorophyll = C6H12O6 + 6O2

What is the word equation for photosynthesis?

Carbon dioxide + water = glucose + oxygen

What occurs in the light dependent stage of photosynthesis?

Photolysis and photophosphorylation

What is photolysis?

The splitting of water using light energy

What is photophosphorylation?

Converting ADP to ATP using light energy

Where does the light dependent stage of photosynthesis occur?

The grana

What occurs in the light independent stage of photosynthesis?

H + CO2 = C6H12O6 + 6O2

Where does the light independent stage of photosynthesis occur?

The stroma

What is photosynthesis effected by?

Temperature, light intensity, CO2 intensity

What does respiration do?

Releases energy from glucose

What is the chemical equation for aerobic respiration?

C6H12O6 + O2 = 6CO2 + 6H2O +36 ATP

Where does aerobic respiration occur?

Cytoplasm and mitochondria

What are the 4 stages of aerobic respiration?

Glycolysis, link reaction, kerb cycle, electron transport system

What is produced from glycolysis?

Pyruvate and 2 ATP

What is produced from the link reaction?

2 CO2

What is produced form the kerb cycle?

4 CO2, 2 ATP

What is produced from the electron transport system?

32 ATP, 6 H2O

What is the chemical equation for lactic acid fermentation?

C6H12O6 = 2C3H6O3

What is the chemical equation for alcoholic fermentation?

C6H12O6 = 2C2H5OH + 2CO2

How much ATP is produced from any anaerobic respiration?

2

What is an obligate anaerobe?

An organism that only anaerobically respires

What is a facultative anaerobe?

An organism that can do both aerobic and anaerobic respiration

2n to 2n

Mitosis

2n to n

meiosis

n to 2n

fertilisation

What are the stages of the cell cycle?

G1, S, G2, M

What does the G1 phase stand for?

Restriction phase

What does the S phase stand for?

DNA Replication phase

What does the G2 phase stand for?

Growth 2 phase

What does the M phase stand for?

Mitotis/meiosis phase

What occurs in the G1 phase?

Cellular growth

What stages are checkpoints?

G1, G2, M

What is a G0 cell?

A cell that doesn't divide

What occurs in the S phase?

DNA replication

What occurs in the G2 phase?

Growth and checking the replicated DNA

What does cyclin + cyclin dependent kinase form?

Mitosis promoting factor

At what point is MPF and cyclin highest in the cell cycle?

G2/metaphase

At what point is MPF and cyclin lowest in the cell cycle?

Anaphase

What does CDK stand for?

cyclin dependent kinase

What are the phases of mitosis?

interphase, prophase, metaphase, anaphase, telophase, cytokinesis

What occurs in prophase?

Nucleus and nucleoli disappear. Chromatin condenses to chromosomes. Centrioles form

What occurs in metaphase?

Chromosomes line up on the cell equator

What occurs in anaphase?

The spindle fibres seperate the sister chromatids and pull them towards opposite poles

What occurs in telophase?

Nucleus forms around the chromosomes. Chromosomes uncoil

What occurs in cytokinesis?

The cytoplasm splits

What is the product of mitosis?

Two genetically identical daughter cells

What kind of cells undergo binary fission?

Prokaryotic cells

What is the product of binary fission?

Two genetically identical daughter cells