100% satisfaction guarantee Immediately available after payment Both online and in PDF No strings attached
logo-home
Summary of Key Concepts Grade 12 Biology $4.35   Add to cart

Summary

Summary of Key Concepts Grade 12 Biology

 35 views  0 purchase
  • Course
  • Institution

This comprehensive summary provides an overview of the essential concepts covered in Grade 12 Biology, designed to facilitate understanding and review of the key topics in the curriculum. The document covers a wide range of subjects crucial for mastering the course, including: Cell Biology: De...

[Show more]

Preview 2 out of 6  pages

  • August 15, 2024
  • 6
  • 2024/2025
  • Summary
  • Secondary school
  • 12th Grade
  • 1
avatar-seller
Page 1: Introduction and Cellular Biology

1. Introduction to Biology

• What is Biology?: The study of life and living organisms.

• Scientific Method: Steps include observation, hypothesis, experiment, analysis,
and conclusion.

2. Cell Structure and Function

• Cell Theory: All living organisms are composed of cells.

• Cell Types:

o Prokaryotic: Simple, no nucleus (e.g., bacteria).

o Eukaryotic: Complex, with a nucleus (e.g., plant and animal cells).

• Organelles:

o Nucleus: Control center.

o Mitochondria: Powerhouse, ATP production.

o Ribosomes: Protein synthesis.

o Endoplasmic Reticulum: Transport (smooth and rough).

o Golgi Apparatus: Modifies and packages proteins.

o Lysosomes: Waste disposal.

o Chloroplasts (plants): Photosynthesis.



Page 2: Cell Cycle and Division

1. The Cell Cycle

• Phases:

o Interphase: G1 (growth), S (DNA replication), G2 (preparation for mitosis).

o Mitosis: Division of the nucleus.

▪ Prophase: Chromatin condenses, spindle fibers form.

▪ Metaphase: Chromosomes align at the equator.

, ▪ Anaphase: Sister chromatids separate.

▪ Telophase: Nuclear membranes reform.

o Cytokinesis: Division of the cytoplasm.

2. Meiosis

• Purpose: Produces gametes (sperm and egg cells).

• Stages: Two rounds of division (Meiosis I and II).

o Crossing Over: Genetic recombination in Prophase I.

o Reduction Division: Chromosome number halved.



Page 3: Molecular Genetics

1. DNA Structure and Function

• DNA Composition: Double helix, nucleotide structure (sugar, phosphate, nitrogen
base).

• Base Pairing Rules: A-T (Adenine-Thymine), C-G (Cytosine-Guanine).

• DNA Replication: Semi-conservative model, enzymes involved (e.g., DNA
polymerase).

2. Gene Expression

• Transcription: DNA to mRNA in the nucleus.

• Translation: mRNA to protein in the ribosome.

• Genetic Code: Codons and amino acids.

3. Mutations

• Types: Point mutations (substitution, insertion, deletion), chromosomal mutations.

• Effects: Silent, missense, nonsense, frameshift.



Page 4: Heredity and Mendelian Genetics

1. Mendel’s Laws

• Law of Segregation: Alleles separate during gamete formation.

The benefits of buying summaries with Stuvia:

Guaranteed quality through customer reviews

Guaranteed quality through customer reviews

Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.

Quick and easy check-out

Quick and easy check-out

You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.

Focus on what matters

Focus on what matters

Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!

Frequently asked questions

What do I get when I buy this document?

You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.

Satisfaction guarantee: how does it work?

Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.

Who am I buying these notes from?

Stuvia is a marketplace, so you are not buying this document from us, but from seller alaatakache. Stuvia facilitates payment to the seller.

Will I be stuck with a subscription?

No, you only buy these notes for $4.35. You're not tied to anything after your purchase.

Can Stuvia be trusted?

4.6 stars on Google & Trustpilot (+1000 reviews)

77254 documents were sold in the last 30 days

Founded in 2010, the go-to place to buy study notes for 14 years now

Start selling
$4.35
  • (0)
  Add to cart