Kramizo
Log inSign up free
HomeCXC CSEC Human and Social BiologyCodominance and multiple alleles including ABO blood groups
CXC · CSEC · Human and Social Biology

Codominance and multiple alleles including ABO blood groups
Practice Questions

20 CXC CSEC Human and Social Biology questions on Codominance and multiple alleles including ABO blood groups, each with instant feedback and a full examiner-style mark scheme.

⚡ Start Quiz on Codominance and multiple alleles including ABO blood groups📖 Read Revision NotesTry one question
✨ Revision guide includes key terms, worked examples and exam technique for Codominance and multiple alleles including ABO blood groups.

Try 2 sample questions on Codominance and multiple alleles including ABO blood groups

Question 1 · 1 mark · Difficulty 1/3

Which row correctly shows the antigens present on red blood cells and antibodies in the plasma for blood group B?

  1. Antigens: A; Antibodies: anti-B
  2. Antigens: B; Antibodies: anti-A
  3. Antigens: A and B; Antibodies: none
  4. Antigens: none; Antibodies: anti-A and anti-B
Show answer & explanation
✓ Answer: BAntigens: B; Antibodies: anti-A
Award 1 mark for B. Blood group B individuals have B antigens on their red blood cells and produce anti-A antibodies in their plasma. A describes blood group A. C describes blood group AB. D describes blood group O.
Question 2 · 1 mark · Difficulty 2/3

A Jamaican couple is expecting their first child. The father has blood group AB and the mother has blood group O. Which blood group is NOT possible for their child?

  1. A
  2. B
  3. AB
  4. O
Show answer & explanation
✓ Answer: CAB
Award 1 mark for identifying that AB is not possible. The father (AB) can pass either I^A or I^B allele. The mother (O) can only pass i allele. Possible offspring genotypes are I^A i (group A) or I^B i (group B). A is incorrect — group A is possible (I^A i). B is incorrect — group B is possible (I^B i). D is incorrect — group O requires ii genotype which cannot occur as father must pass either I^A or I^B.
⚡ Start a Quiz on Codominance and multiple alleles including ABO blood groups
20 questions · 25 min · free

CXC CSEC Human and Social Biology: Codominance and multiple alleles including ABO blood groups FAQ

How many CXC CSEC Human and Social Biology questions on Codominance and multiple alleles including ABO blood groups are there on Kramizo?
Kramizo currently has 20 exam-board-aligned practice questions on Codominance and multiple alleles including ABO blood groups for CXC CSEC Human and Social Biology, with new questions added every week. Each question gives you instant feedback and a full examiner-style mark scheme that tells you exactly what would earn marks on a real CXC paper. The questions span the full difficulty range — from straightforward recall (level 1) right up to multi-step reasoning and evaluation (level 3) — so the bank works for first-pass revision and final exam-week stress testing alike.
Is Kramizo free for CXC CSEC students preparing for Human and Social Biology?
Yes — completely free. Every student gets 45 questions a day on the free plan, with no card required and no trial countdown. That free quota works across every subject and every topic in our bank, so you can mix Codominance and multiple alleles including ABO blood groups practice with other Human and Social Biology topics or even switch to a totally different CXC subject without paying anything. Kramizo's optional Pro plan removes the daily cap and adds detailed progress analytics, but the free tier is the real product — used by thousands of GCSE, IGCSE and CSEC students.
Are the Codominance and multiple alleles including ABO blood groups questions aligned to the official CXC CSEC Human and Social Biology syllabus?
Every question is written against the published CXC CSEC Human and Social Biology specification, including the exact command words (state, describe, explain, calculate, evaluate, etc.), mark allocations, and difficulty tier you'd see on a real CXC paper. Explanations are written in the style of official examiner mark schemes — they tell you what is being awarded marks and why distractors are wrong, not just whether you got it right. The bank is continually refined to match the latest syllabus updates from CXC.
How is Codominance and multiple alleles including ABO blood groups typically tested on CXC CSEC Human and Social Biology papers?
Codominance and multiple alleles including ABO blood groups appears across multiple question types on real CXC CSEC Human and Social Biology papers — most commonly as multiple-choice questions in the objective section, structured short-answer questions in the main paper, and occasionally as part of an extended response. Kramizo's practice bank reflects that mix: 4-option MCQs, true/false statements, fill-in-the-blank key terms, multi-select questions, and ordering questions. Working through the bank gives you exposure to every question style examiners actually use.

Lock in Codominance and multiple alleles including ABO blood groups before exam day.

Start practising in 30 seconds — no card required.

⚡ Start Quiz Free →