Grade 8 Science Reviewer

Comprehensive review flashcards covering the human digestive system, plant transport, genetics, taxonomy, and cellular energy processes based on the Grade 8 Science Reviewer.

What are the four stages of food processing in the human digestive system?

1. Ingestion, 2. Digestion, 3. Absorption, 4. Elimination

Which enzyme is found in the mouth and what is its specific function?

Salivary amylase; it breaks down starch into simple sugars.

What is the name for the wave-like muscle contractions that move food through the esophagus?

Peristalsis

Which two substances make up the gastric juices in the stomach to break down proteins?

Hydrochloric acid and pepsin

What is the name of the soupy mixture of food and gastric juices formed in the stomach?

Chyme

What are the tiny, finger-like projections on the interior wall of the small intestine called?

Villi

What is the primary function of the Large Intestine (Colon)?

It reabsorbs water and mineral salts, solidifying waste into feces.

What substance does the liver produce to emulsify fats?

Bile

Which organ stores and concentrates bile before releasing it into the small intestine?

Gallbladder

Which three digestive enzymes are produced by the pancreas?

$\text{lipase}$ , $\text{protease}$ , and $\text{amylase}$

Which vascular tissue in plants transports water and minerals upwards in a one-way flow?

Xylem

How does the flow of Phloem differ from the flow of Xylem?

Phloem has a two-way flow transporting sugars ($\text{glucose}$), while Xylem has a one-way flow for water and minerals.

Who is recognized as the Father of Modern Genetics?

Gregor Mendel

What is the definition of an Allele?

An alternate version of a gene (e.g., $T$ for tall, $t$ for short).

What is the difference between Genotype and Phenotype?

Genotype is the genetic combination of alleles (e.g., $TT$, $Tt$, $tt$), while Phenotype is the physical expression or appearance (e.g., Tall, Short).

What is the genotypic ratio of a monohybrid cross between two heterozygous tall plants ($Tt \times Tt$)?

$1\,TT: 2\,Tt: 1\,tt$ (or $1: 2: 1$)

What is the classic phenotypic ratio produced by a dihybrid cross between two fully heterozygous parents ($RrYy \times RrYy$)?

$$9: 3: 3: 1$$

In a pedigree chart, what do the square and circle symbols represent?

Square represents a Male; Circle represents a Female.

On a pedigree chart, what does a horizontal line between a square and a circle indicate?

Marriage or mating

Who established the science of taxonomy for naming and classifying living organisms?

Carl Linnaeus

What are the eight taxonomic levels in order from broadest to most specific?

Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species

What are the two components of an organism's scientific name in binomial nomenclature?

The Genus (capitalized) and the species (lowercase).

In which cell organelles do photosynthesis and cellular respiration occur, respectively?

Photosynthesis occurs in the Chloroplast; Cellular Respiration occurs in the Mitochondrion.

What are the reactants (inputs) required for cellular respiration?

$$\text{Glucose} + \text{Oxygen}$$

What is the main purpose of Cellular Respiration?

To break down glucose to release usable energy in the form of $ATP$.