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What form of energy do plants convert during photosynthesis

Plants convert solar (light) energy into chemical energy (glucose).

What are the basic requirements for photosynthesis

Light, carbon dioxide (CO₂), and water (H₂O).

What is the balanced photosynthesis equation

Light + 6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂.

What are the products of photosynthesis

Glucose (C₆H₁₂O₆) and oxygen (O₂).

Where does photosynthesis occur in plant cells

In the chloroplasts.

Where does cellular respiration occur in plant cells

In the mitochondria.

How are photosynthesis and cellular respiration interconnected

Photosynthesis produces glucose and O₂ used in respiration; respiration produces CO₂ and H₂O used in photosynthesis.

What is the function of guard cells

They regulate the opening and closing of stomata for gas exchange and water loss.

What is the function of stomata

They allow CO₂ to enter and O₂ to exit the leaf.

When are stomata open versus closed

Open when water is abundant and conditions are cool; closed when hot or dry.

What is the role of chlorophyll a and b

They capture light energy, mainly in blue and red wavelengths.

What do accessory pigments (carotenoids, xanthophylls) do

They capture additional light wavelengths and protect chlorophyll from damage.

Which light color is reflected by chlorophyll

Green light.

How could you design an experiment to test photosynthesis requirements

Remove one factor (light, CO₂, or pigment) and measure oxygen production or starch formation.

What is asexual reproduction

One parent produces genetically identical offspring.

What is sexual reproduction

Two parents produce genetically diverse offspring.

What is an advantage and disadvantage of asexual reproduction

Advantage: fast and energy efficient; Disadvantage: no genetic variation.

What is an advantage and disadvantage of sexual reproduction

Advantage: increases genetic variation; Disadvantage: slower and requires more energy.

What is the purpose of mitosis

Growth and repair of cells.

What is the purpose of meiosis

Production of gametes (sperm and eggs).

What is the stages of mitosis

Prophase, Metaphase, Anaphase, Telophase, and Cytokinesis.

What happens during meiosis I and II

Meiosis I separates homologous chromosomes (crossing over occurs); Meiosis II separates sister chromatids → 4 haploid cells.

What is crossing over and why is it important

Exchange of genetic material between homologous chromosomes; increases genetic variation.

What is the difference between diploid (2n) and haploid (n) cells

Diploid has two sets of chromosomes (body cells); Haploid has one set (gametes).

What are the male reproductive parts of a flower

Stamen = anther (makes pollen) + filament.

What are the female reproductive parts of a flower

Pistil = stigma (receives pollen) + style + ovary (contains ovules).

What is pollination

Transfer of pollen from anther to stigma.

What is fertilization in plants

Fusion of sperm from pollen with egg in ovule.

What are the male gonads and their function

Testes; produce sperm.

What are the female gonads and their function

Ovaries; produce eggs.

What is the difference between external and internal fertilization

External: occurs outside the body (fish, amphibians); Internal: inside the body (mammals, birds).

What are the risks of sexual activity in humans

STIs and unintended pregnancy.

What are the base-pairing rules for DNA-DNA

A-T, C-G.

What are the base-pairing rules for DNA-RNA

A-U, C-G.

How is genetic information stored in DNA

In the sequence of nucleotide bases.

What is the structure of DNA

Double helix with a sugar-phosphate backbone and nitrogenous bases.

What is chromatin

Uncoiled DNA used for gene expression.

What is a chromosome

Condensed DNA used during cell division.

What happens during transcription

DNA is used to make mRNA (in the nucleus).

What happens during translation

mRNA is read by ribosomes to assemble amino acids into a protein (in the cytoplasm).

What are the roles of mRNA, tRNA, and rRNA

mRNA carries the code; tRNA brings amino acids; rRNA makes up ribosomes.

How do you use a codon chart

Match each 3-base mRNA codon to its corresponding amino acid.

What is the difference between transcription and translation

Transcription = DNA → mRNA (nucleus); Translation = mRNA → protein (cytoplasm).

What is a silent mutation

Base change that doesn't alter the amino acid.

What is a missense mutation

Base change that alters one amino acid.

What is a nonsense mutation

Base change that creates a stop codon prematurely.

What is a frameshift mutation

Insertion or deletion that shifts the reading frame.

How much genetic variation exists between humans

About 0.1% of total DNA.

What is DNA profiling used for

Identifying individuals or determining genetic relationships.

How do mutations affect proteins

They can change the amino acid sequence, altering protein shape or function.