Events of fertilisation - Study guides, Class notes & Summaries

Describe the events of fertilisation that occur after the acrosome reaction. correct answers -Membrane of sperm and egg cell fuse together -cortical granules release contents into zona pellucida -Zona pellucida thickens -Haploid nuclei fuse Explain how phospholipids form a cell surface membrane correct answers -Hydrophilic parts associate with water -Hydrophobic parts repel water -a bilayer forms with hydrophobic parts pointing in towards the centre of the bilayer Describe the role...

Edexcel A-Level Biology Exam Questions With 100% Correct Answers 2023

Describe the events of fertilisation that occur after the acrosome reaction. - -Membrane of sperm and egg cell fuse together -cortical granules release contents into zona pellucida -Zona pellucida thickens -Haploid nuclei fuse Explain how phospholipids form a cell surface membrane - -Hydrophilic parts associate with water -Hydrophobic parts repel water -a bilayer forms with hydrophobic parts pointing in towards the centre of the bilayer Describe the role of the CFTR protein in en...

GCSE BIOLOGY F Foundation Tier Paper 2F Time allowed: 1 hour 45 minutes For Examiner’s Use Question Mark 1 2 3 4 5 6 7 8 9 10 TOTAL Materials For this paper you must have: • a ruler • a scientific calculator. Instructions • Use black ink or black ball-point pen. • Pencil should only be used for drawing. • Fill in the boxes at the top of this page. • Answer all questions in the spaces provided. • If you need extra space for your answer(s), u...

Suggest the advantages of the change in blood flow in blood vessels during exercise. [3 marks] - answer--more blood flow to muscles during exercise -supplying more glucose and oxygen/ removing carbon dioxide/ lactic acid/ heat -for high rate of respiration/ to meet increased demand for energy Explain how microorganisms contributed to the increase in temperature during processing of organic waste. [2 marks] - answer-respiration produces heat explain the advantage of showing the data using...

AQA A level Biology Revised Questions And Answers 2023 Describe how you would use a biochemical test to show that a solution contained a nonreducing sugar, such as sucrose. [3] - CORRECT ANSWER-,first reducing sugars test; boil with dilute HCl acid then Neutralise with NaHCǑ, add benedict and heat to 95 degrees C brick red ppt forms if reducing sugar is present Describe a chemical test you could carry out to show that a piece of coconut contains lipids. [3] - CORRECT ANSWER-(Crush in)...

Regulatory gene - answer-a gene that codes for a transcription factor, so controls the expression of structural genes Structural gene - answer-gene that codes for polypeptide Mutation - answer-a random change in the sequence of bases in an individual gene, or in the structure of the chromosome (which changes the sequence of genes on the chromosome) Examples of mutagenic agents - answer-x-rays, uv light (physical), nitrous acid (chemical) & some viruses (biological agents) What can ch...

Edexcel A-level biology exam questions and answers(2022 exam graded A)

GED questions with complete solution 2022heritable characteristics traits linked to DNA that can be passed onto offspring 3 conditions required for natural selection heritable characteristics, variation between traits of individuals, differential fitness between individuals differential fitness differing ability of individuals to survive, reproduce and pass their genes down to the next generation evolution genetic change due to change of allele frequency in a population ...

Reproduction enables a species to live generation after generation. Reproduction in organisms can be broadly classified into a sexual and asexual reproduction. Asexual reproduction does not involved the fusion of gametes. It is common in organisms that have a relatively simple organisms such as fungi, algae and some invertebreate animals. The offspring formed by asexual reproduction are identical and can be referred as clones. Sexual reproduction involves the formation and fusion of gametes. I...