Biology Quiz Questions and Answers
What is a dihybrid cross?
A genetic cross involving two individuals that are heterozygous for two different traits.
In comparison to eukaryotes, prokaryotes
Are smaller
According to the central dogma, what is the intermediate molecule involved in the flow of information in a cell?
mRNA
Why does testosterone, a lipid-soluble signaling molecule that crosses the membranes of all cells, affect only target cells?
Intracellular receptors for testosterone are present only in target cells.
In the formation of biofilms,
Read MoreDivided attention
Eye- The eyeball is the spherical organ of sight. Its diameter of about 2.5cm. It lies in a bony cavity within the facial skeleton known as the bony orbit. The anterior one- sixth is much more convex than the posterior part.
Anatomically, the eyeball divided into 3 parts;
Fibrous or outer coat. Vascular or middle coat. Nervous or inner coat.
1. Fibrous coat: The fibrous layer of the eye is the outermost layer. It is posteriorly formed by the sclera and anteriorly by cornea. Their main functions
Read MoreRed Winemaking Process: From Grape to Glass
Red Winemaking:
The process of red winemaking involves fermenting the wort (grape juice) with the solid parts of the harvest (skins and seeds). This extraction process imparts color, flavor, and mouthfeel to the wine.
Operations Before Vinification:
Collection and Transport:
Harvesting grapes carefully is crucial to ensure the clusters arrive intact and prevent premature fermentation. Here’s how:
- Minimize transfers.
- Prevent grapes from being crushed.
- Use easy-to-clean containers to avoid contamination.
The Fundamentals of Genetics: From Cells to Inheritance
Cellular Reproduction
Definition
The process by which cells divide to produce new cells.
Types
- Mitosis: Division of a parent cell into two genetically identical daughter cells, typical for somatic cells.
- Meiosis: Division process that reduces the chromosome number by half, resulting in four haploid cells, typical for germline cells.
Genome
Definition
The complete set of DNA, including all of its genes, in an organism.
Key Points
- Contains all the information necessary for the structure, function, and regulation
Placenta and Fetal Development: A Comprehensive Guide
Placenta Formation
The placenta is a vital organ that develops during pregnancy to facilitate the exchange of nutrients, oxygen, and waste products between the mother and the developing fetus. The journey begins even before implantation.
The fertilized egg, called a blastocyst, contains an outer layer of cells called trophoblasts. These are the key players in placenta formation.
Early Development (Week 1-3)
Implantation: Around 7-10 days after fertilization, the blastocyst implants in the uterine lining.
Read MoreBiochemistry Basics and Key Concepts
1. Cellular Respiration
Glycolysis
- Formula: C6H12O6 + 2 NAD+ + 2 ADP + 2 Pi → 2 C3H4O3 (pyruvate) + 2 NADH + 2 ATP + 2 H2O + 2 H+
- Key Points:
- Occurs in the cytoplasm.
- Glucose (6C) → 2 Pyruvate (3C).
- Net gain of 2 ATP and 2 NADH.
Citric Acid Cycle (Krebs Cycle)
- Formula: Acetyl-CoA + 3 NAD+ + FAD + ADP + Pi + 2 H2O → 2 CO2 + 3 NADH + 3 H+ + FADH2 + ATP + CoA
- Key Points:
- Occurs in the mitochondrial matrix.
- For each Acetyl-CoA, 2 CO2, 3 NADH, 1 FADH2, and 1 ATP are produced.