Science Grade 10 - Flashcards (Based on Lecture Notes)

A curated set of practice flashcards covering key concepts from biology, chemistry, and physics chapters in the notes.

What is the basic unit of life?

Cell.

State the three main ideas of the cell theory.

1) The cell is the structural and functional unit of life. 2) All organisms are made up of one or more cells. 3) New cells form from pre-existing cells.

Name two key differences between plant and animal cells.

Plant cells have a cell wall, chloroplasts, and a large central vacuole; animal cells lack a cell wall and chloroplasts and have smaller vacuoles.

What is the function of mitochondria?

Powerhouse of the cell; produces energy via cellular respiration.

What is the function of the nucleus?

Stores genetic material and controls cellular activities.

What is the role of ribosomes?

Sites of protein synthesis.

What is the function of rough endoplasmic reticulum?

Synthesizes and transports proteins with ribosomes attached.

What is the function of the Golgi apparatus?

Packages and ships proteins and lipids for secretion or delivery.

What is the function of vacuoles?

Store water and other substances; in plants, a large central vacuole maintains turgor.

What is the function of chloroplasts?

Site of photosynthesis; contains chlorophyll.

Why do plant cells have a cell wall and chloroplasts but animal cells do not?

Cell walls and chloroplasts are characteristic of plants; animals lack these structures.

How many chromosomes are in a typical human somatic cell?

46 (23 pairs).

What is mitosis?

Cell division that produces two identical diploid daughter cells.

What is meiosis?

Cell division that halves the chromosome number to form haploid gametes.

Who proposed the planetary model of the atom?

Ernest Rutherford (Bohr later proposed electron shells around the nucleus).

What is first ionisation energy?

The minimum energy required to remove one electron from a gaseous atom to form a uni-positive ion.

What is electronegativity?

The ability of an atom to attract electrons in a covalent bond; increases across a period and decreases down a group.

How do oxide properties change across a period?

Oxides become more acidic and less basic as you move left to right across a period.

Differentiate metals from non-metals (basic distinctions).

Metals are typically good conductors, malleable, ductile; non-metals are poor conductors, brittle. Graphite is an exception as a non-metal that conducts.

What is an ionic bond?

Electrostatic attraction between oppositely charged ions formed by electron transfer.

What is an ionic lattice?

A three-dimensional arrangement of ions in ionic compounds (e.g., NaCl lattice).

What is a covalent bond?

A bond formed by sharing electrons between atoms.

Name two carbon allotropes discussed and one key difference between them.

Diamond and Graphite; diamond forms a 3D covalent lattice with very high hardness, graphite has layered structure with weaker interlayer forces.

What is a polar covalent bond?

A covalent bond where electrons are shared unequally due to electronegativity differences.

What are intermolecular bonds and which important example is discussed?

Forces between molecules; hydrogen bonds are a key example, influencing water properties.

What is the chemical formula for water?

H2O.

What is Ar in chemistry?

Relative atomic mass, the mass of an atom relative to 1/12 of the mass of C-12.

What is Avogadro’s number?

6.022 x 10^23; number of basic units in a mole.

What is a mole?

Amount of substance containing Avogadro’s number of basic units (atoms, molecules, or ions). It links mass to amount of substance.

What is the relative formula mass of NaCl?

58.5 (sum of relative atomic masses Na = 23 and Cl = 35.5).

What is a relative molecular mass (Mr)?

Sum of the relative atomic masses of all atoms in a molecule.

What are isotopes?

Atoms of the same element with the same atomic number but different mass numbers due to different numbers of neutrons.

Give an example of hydrogen isotopes.

Protium (1H), Deuterium (2H), Tritium (3H).

What are two types of friction and their definitions?

Static friction (pre-movement), limiting (maximum static friction to start movement), dynamic (kinetic friction when moving).

What factors affect limiting friction?

Nature of contact surfaces and the normal reaction; not the contact area.

Define moment (turning effect of a force).

Moment = force x perpendicular distance from the rotation axis; unit N·m.

What is a couple of forces?

Two equal and opposite forces whose lines of action are parallel but separated, producing rotation without translating the body.

What conditions define equilibrium under two forces?

The forces must be equal in magnitude, opposite in direction, and lie along the same line.

What conditions define equilibrium under three coplanar parallel forces?

One force must be equal in magnitude to the resultant of the other two and opposite in direction; all three forces are coplanar.

What is the difference between speed and velocity?

Speed is the rate of distance travel (scalar); velocity is the rate of change of displacement (vector, includes direction).

What is the area under a velocity-time graph?

Displacement.

What is gravitational acceleration on Earth (g)?

Approximately 9.8 m/s^2 (negative when upward). On the Moon it is ~1/6th.

What is the difference between mass and weight?

Mass is the amount of matter (kg); weight is the force due to gravity (N), W = m g.

What is the Biuret test used for?

Detects proteins; a color change to purple indicates protein presence.

What is the Sudan III test used for?

Detects lipids; appearance of red fat globules indicates lipids.

Which solubility tests help distinguish proteins, carbohydrates, and lipids in foods?

Starch test with iodine; Benedict’s test for reducing sugars (glucose); Sudan III for lipids.

What are carbohydrates classified into, and give examples of each?

Monosaccharides (glucose, fructose, galactose); Disaccharides (maltose, sucrose, lactose); Polysaccharides (cellulose, starch, glycogen).

What is the formula for glucose and what do monosaccharides do?

Glucose formula: C6H12O6; monosaccharides are the simple sugar units and building blocks of carbohydrates.

What is photosynthesis equation as given in the notes?

Carbon dioxide + water → glucose + oxygen (with light energy and chlorophyll).

Describe the nucleus, mitochondrion, Golgi, ER, ribosome, and vacuole roles in a cell.

Nucleus: stores genetic material; Mitochondrion: energy production; Golgi: packaging/secretion; ER (rough): protein synthesis; ER (smooth): lipid synthesis/transport; Ribosome: protein synthesis; Vacuole: storage (plant cell large central vacuole).

What are autotrophs and heterotrophs?

Autotrophs produce their own food (photosynthesis or chemosynthesis); heterotrophs obtain energy from consuming others.

What is the difference between two- and three-force equilibrium in physics?

Two forces: equal in magnitude, opposite in direction along same line. Three coplanar parallel forces: one force equals the resultant of the other two and is opposite in direction.